David...this is an awesome project, but u definitely know what u r doing in regards to DC currents and voltages etc and the use of meters, heating etc, what is your background, are u a technician...thks..i would love to try that set up but not understanding the principles of DC electricity, one could harm himself..thks
Can I buy that battery from you? I have a back injury at the moment and can't get around to do much. I am living on my sailboat in Seabrook Texas and need a decent power supply. I would appreciate it. If you aren't using it that is?
It cost him $ 440, less his labour, a battery that spec, worth 900 to 1100 k, so ill assume he means, he saved 500, if he sells them for 900,he made 500,for that day project, but he should say this , tp not look click baitish
SON! probably the best presentation of any subject I have watched on u'tube! I've been to automotive and aircraft schools off and on over the 55 years in the mechanical field. I had only a couple of instructors that presented the info as concise as your did, and that's including speech delivery, clear! Thanks!
Its people like you that make youtube a great place. I know people come to youtube for different reasons, some purely entertainment, some news, I do sometimes for those reasons also. My biggest reason for coming to youtube and spending countless hours on it, is to learn from people like you, it has allowed me and millions of people around the world to watch great videos like this to learn new things that otherwise we would be clueless about. Thx for the video and clear explanations and I wish u the best in 2021!
Thank you David, alot people make comments that just rediculous and waste of time to say, instead of being appreciative of knowledge you share and time given to share with others. So thank you.
For increased cell life, you don't want to use 100% of the capacity. The peak and valley of the charge curve cause the most wear on the cells. So if you trim 5-10% off the top and bottom you get extended life. So if the cells will go as high as 3.65, trim that to 3.6 and if the bottom is 2.8, maybe bring that up to 2.9 or even 3.0v. You would still use 80-90% of the capacity, but you'd get another couple years of use out of those cells.
I'm sure you already know this but cells with built in battery protection circuits tend to be longer, even though they can be marked as 18650. Some of these circuits can add 5mm to the length and this may be why. If you rip the plastic wrapper off one, you might find one tacked onto the end of a cell.
Awesome thing to build your own battery David! Amazing what you have learned about all this stuff because you were not afraid to try. Your kids are also watching and learning. They'll be awesome as well. You and your wife are great parents.
For the amperage you intend to pull, I strongly suggest you refold your positive terminals in the other direction, as the outside of the battery cells are actually negative if and and the insulations get damaged, so with the potential heat in real use, folding your positive wires to not touch or be in close proximity to the side wall seems to be a safer choice.
Exactly my thoughts! I really hope he had some sort of insulation in there behind the bus bar... I was waiting for one of the solder blobs to go through the cell sleeve and arc out.
I like how you suggest he fold it as opposed to just not using wide open huge rails. smaller rails, rails snapped into the structure, COVERED... nope! fold it the other way. that's worth the time!
Greetings from Russia David! I would advise you to charge the battery with a balanced charger, bypassing bms, and entrust the board only with a protective shutdown. I do not trust balancing to these boards (my personal humble opinion), and balancing is not needed every time if the cells are new and from the same batch. Good luck with your projects!
I'm liking these cells and the battery box... if you did 80 cells in the box and you did a 48v battery 16s5p you could make a nice 25ah battery for your 48 volt inverter. All you need is a 16s bms.
I am given to understand that some BMS units can work in series with others of the same or similar BMS type, so you could actually build several batteries of 12V 25AH and put them in series for either 12, 24, 36, 48, 60, or 72 volts. But check very carefully that the BMS is rated for the maximum voltage configuration!
wow man i have never seen such a detailed build, most people will stop after the spot welding, but that final parts cost sheet is the icing on the cake.
I can't believe I forgot about this diy favorite of mine from way back with the salvage car hybrid battery buid for the garage/house power bank. Or the test and trial of finding the right power inverter the solar panels and solar water heater system that was built. Man ,now finding the latest Lytham 14 volt clean diy .. nice! Ty Dave p.
Thanks for the great information. Might I suggest a diagram showing your circuit layout before you begin... It might help us older guys who learned everything reading manuals. Lol. Thanks again..
Good project bud, that's not a bad value for the battery with knowing what's inside. I recently bought a premade lithium battery from amazon that was suppose to be a drop in replacement for my motorcycle, received it and it felt very heavy for a lithium battery, pulled it apart to find it was made up of used 18650 cells with 4 different model cells in use inside and had no internal bms at all, just lots of snot covering everything to keep everything glued together.
I was going to buy one and once I saw the prices I laughed my ass off. It's bad enough the raping they do to you for a damn lead acid bike battery and I've always hated buying them so since I have piles and piles of 18650's and use them for everything I just put 2p3s together and wrapped it with some black tape, soldered it together with some 12 guage. You do know everyone says you can't solder them right? Bullshit I've soldered thousands of these things and never once had one go bad and I'm not very good with this piece of crap gun I've got and most times the battery is beyond hot and can't be touched and I've never had a problem. So I just wanted to see if it would power my klr 650 and do what it needs and it was more than enough. Considering that 18650's are free everywhere all day long you don't need a bms. I've left these things on for months in the rain, snow, in the dirt and they were most surely dead and they charge right back up everytime. Almost every single thing they ever told us about Lithium is pure lies my friend and if anyone was going to have one blow up it would have been me since I've always tried but to no avail so all I can say is you could make yourself a backup battery for about NOTHING and just get a charger circuit for 12 bucks so you can use lipo instead of lifepo and your alternator can easily handle your electricity needs. If you replace some bulbs with Led their is no reason to buy the real thing. If you truly fill the whole battery space your bike has you'll have way more than enough power and you'll never get a dead battery from flooding it or a fouled plug and that to me is so much better than lead acid since you should know if you take one below 10 volts you basically guarantee it won't be there for you when you truly need or want it as is the character of L/A junk. Bms are for suckers or large expensive projects, you could probably start your bike with just 3 18650's!! Try it if you don't believe me, wouldn't take you more than 10 minutes to make one up and see for yourself and in case you're wondering what I meant by free just t hink recycle, that is where the proven ones are with one dead cell among them and in my experience they defy all the myths the internet is full of. Peace Sizzlean
dont talk if you dont know what you are talking about... Only because they look like protected cells doesnt mean they are. And in fact, they ARE NOT PROTECTED.
When cells wear down they will eventually fail. Either as a short or open connection, however the later condition is rare. In other words. This battery has 80 points of possible failure! IMHO you should have used some "nickel-strip" with built-in fuses to avoid setting your house on fire.
Good call. Expensive, industrial grade packs cut slits in the nickel strip to create "fusable links". If a cell shorts and exceeds a certain current, the strip burns away and the cell is isolated. I haven't yet seen a DIY battery project video where the author does this. It would be interesting to see what the chances of such a failure are.
Solid Build!! Only critique I have is at @12:52. When you bend your busbar back, it's now in a place where it can rub on the can. Since the can is negative, if you use this battery in a mobile application, you have created a fire risk when the bar rubs through the cell's original insulation. Some of the battery paper, maybe 2 layers, would help that a lot.
Whoa, whoa, whoa. Weren't you going to compare this to buying an off the shelf equivalent? So yours cost $440 to build and you limited it to 12.9V @50A. So what off the shelf unit of that same output are you comparing it to and how does this save you over $500? And for that matter, how is it "$500/day"? Is there an ATM included?
It occurs to me that these are questions that the content provider would want to put to bed right away. Somewhat disappointing to see that they have gone unaddressed.
When this video was released almost 4 years ago a 12v 100Ah was around $1000, a year earlier $1500. Now you can get them for as low as $250 so this content not so applicable today as the prices of the 32650(32700) haven't dropped inline with larger cells. So, imo, the $500/Day is fairly accurate for the time. $500 savings and approximately a day to build. The 50 amp limit was a personal choice and once again, imo, a good one. My whole house doesn't run 50 amps with everything turned on.....for 50 amp loads you are wanting a much larger battery!!!!! Great video.
You need tape between your positive terminal and the side of your battery, which is negative. A tiny bit of rubbing and you will dead short the positive of those 20 cells to the negative of those 20 cells. A couple layers of tape and some insulating board is needed or this will one day become a bomb.
To clarify for Dave, Ecospider5 is talking about the bit at 12:55 ish where the nickel strip for the positive terminal is folded around to the side of the cells. Here the heatshink around the cells is a potential point of failure. If the strip were not folded over like that there wouldn't be an issue.
I was going to post a comment about this. This is very critical, since the nickel strip sharp edge could easily cut into the battery shrink wrap. I would try to fix this sooner rather than later. Other than that great build.
Your positive bus bar is resting up against the sides of the cells which will cause a short if it wears through the cell wraps. You should put kapton tape and/or sticky paper.
Well done I use to install solar systems in the 80s we used lead acid fork lift battery's. The battery banks were usually only 48 volt systems so there was not a hazard from getting shocked but a short across a battery battery bank will do severe damage to anything near by. Take every precaution to not let the positive and negative leads touch the amperage is very height and will weld and or vaporize conductors.
Three years ago I had to replace the 1.5 KWH house battery bank in my sailboat. I looked at Lithium batteries and the price worked out to about $1800, so I replaced the old lead-acid batteries with... new lead acid batteries for about $600 (6 T105's from Sam's Club). If this build can hit 1500 WH for $400 My next replacement will (finally) be lithium. It looks like the build is 1/3 smaller than the lead acid bank so I could (finally again) put in a larger bank Putting it together gives me something to do when it's not sailing season ;=) . Looks like we've rounded a corner regarding price. Thanks for a complete and highly informative vid.
Crappy part about the lead acids is they seem to start dying within 6 months to a year even if you rarely use them. You shouldn't notice any degrade for at least 3-5 years with a lithium when rarely used.
I would have put in an active balancer, I had the same issue of High voltage disconnect, and an active balancer solved this issue. Now getting full charge in quicker
I was a diesel mechanic and my first job was to fix electrical problems occuring in the fleet and I used the screw cutting feature of my wire crimper quite a lot as the stockroom only carried these in 2" lenght. After a few dozen screws, the crimper joint gets loose, the cut is not as straight and the screw is hard to remove. You have to reset the rivet on the crimper. I'm not yet ready to swap my 12 golf cart batteries for Lithium batteries but I would DIY a few if I needed to start from scratch. Nice video with a lot of info, trics and tips. Thanks DavidPoz and take care.
This is a somewhat unsafe battery. Timestamps to where build mistakes were made. 11:08 round your positive corners you madman. No fishpaper rings either. Sure it takes an extra $10 and 30min, but it's worth it for the peace of mind. 12:54, you folded a positive line over the negative casing of the battery. Meaning that thin pvc shrink the batteries are housed in is the only thing preventing a dead short. Put some fishpaper between them. 15:56 should be discharging from both "corners" it's fine I guess, but not ideal when you could have easily soldered the wires on each. When charging to make perfect balance. Set power supply to slightly less than the balance current of the bms. (Usually 100mv) this allows the bms to burn off the high cells at the same rate of charging so no overvoltage cutoff will happen while balancing.
@mike h So the internal heating and cooling of the cells will not make them expand at all? And you are willing to bet your house on that? .... you know that no insurance will pay up on a self built battery fire ;0) If you want to see battery packs igniting look up Louis Rossman ...... different battery type but still the same reaction!
Seems like you know how to ride stuff and that's about it........ Where are your battery builds? And calling someone a mad man just 'cause you think you know better? Juvenile! Very Juvenile.
@@totherarf the parralel configuration can handel 100A as calculated he because of the BMS setup and the DC braker can't draw more than 50A. Those cells can handel 20A constant he is only going to draw half that when fully loaded. After that, the DC braker or the BMS will shut down. Unless those batteries are drawn up to full capacity there should be no swelling of the cells. So please tell me, why the scare tactics? We all know how dangerous these batteries can be, but you completly overlooked all the safty measures that David took.
For me it does not look professional due to some severe points missing: - How to protect against short circuiting when attaching the bms - Design flaws: the "prepared" end nickel construction has only the 8mm strips to combine the two left and right sided cell strings and those can easily provide 20 amps each, but you told us the strip is good for 5 amps. That is a severe heating source! - Not repair-friendly: welding 20 cells makes them very hard to find broken ones and to replace them - The welding points can heat up - More information about the welding hardware would be desirable - and lots more
I loved every minute of this! This is exactly how my mind works, so it's not 'work' at all. It's challenging, exciting, and makes me want to get back to being inventive and creative. I'm also eternally thankful to my ancestors for their contributions to my DNA. I know my gifts and shortcomings, and as I age, my ability to handle disappointments has improved dramatically. Most all you guys and possibly some females know exactly what I'm saying! I love all of you as I love myself. I wish the very best to you all!!!
You know honestly I don’t remember the last time I have watched a 30min+ video but man I have really enjoyed yours I don’t own a solar panel, I don’t know the first thing about electricity or batteries but I have really enjoyed it Keep it up 👍🏼 Love from Syria 🇸🇾
The great thing is you can learn so much from his videos and the other guy (j-who) that you can start making your own battery packs. If you teach yourself basic electrical how electicity flows fom positive to negative and how to add voltage and amperage depending on serial or parallel circuits, you can learn to do everything this guy is doing for yourself and.configure batteries in way that meet your own exact needs. It's not as hard as some people think. One day as a kid, I learned electronics using an old RadioShack 100 in 1 electronic experiments set. Now I'm an adult and thanks to the encouragement from RUclips am finding ways to creatively adapt an changing out the types of batteries various goods around the house use for 18650 packs because the limited battery types of 9V, AA, AAA, and C size conventional batteries annoyed me so much with their short lives and constant recharging or replacement. Its easier than you think. It just takes a little determination to learn what's necessary to figure things out. With RUclips, you can litterally teach yourself anything that isn't a corporate secret.
Just an idea. To avoid heating up the batteries with the soldering iron, solder the wire from the balancing lead to a small piece of nickel strip, then spot weld that piece to the battery terminal.
Really appreciate your attention to detail. However for me it’s more educational than practical. I don’t think I’d have the same confidence in my ability. I am sure there are viewers who could DIY this but not for me. Too many ways this could go south. As they say I have just enough knowledge to be dangerous 😀
No problem. This video is over a year old, and there are many more options on the market today. I'd buy this one instead of DIY today: signaturesolar.com/eg4-wp-lithium-battery-12v-100ahs/?ref=4_rHcgZ9x-TiF- Back when I was filming this the 12V, 100Ah, batteries on the market were about $900+.
ONE HUNDRED EIGHTY THOUSAND DOLLARS A YEAR - FREE $500 a day, for a year you'll SAVE $182,500.00? RIGHT ? At 76, I live off grid with solar and lithium. We NEED more of it. We NEED folks like you. We DON'T need Click Bait ! !
If you want to charge at 50A then your breaker should be 60A. Unless you have a 100% rated breaker, you normally have to limit the continuous current through the breaker to 80% or 40A with this 50A breaker.
People used to rebuild their lead/acid batteries using sheet lead for plates. You can even recycle the lead and sulphuric acid, if you know what your doing. Robert Murray Smith did a RUclips video about it. He got the directions from a book from the 1920's or so. It might be good knowledge in a post apocalyptic, post industrial, post SHTF time.
Me either and I been using that tool off and on for 30 years lol, amazing you always learn something new from the weirdest of places lol. Loved the video, but have no idea why I watched it all lol, didn't understand half of it but it was fun to watch and made me brain think lol. Have a great day :).
@@snoozin99 yeah Hope I can get a metric one here in Thailand hahaha then theres the minor problem of getting some screws Dont come to live in thailand unless you just want to grow mangoes and farm chickens and get old :-(
Have you ever tried making batteries out of PVC? I recently made some 12v battery sticks as experiment by cutting a section of 3/4 pvc conduit, pvc end caps, bolts, cone springs, and washers. I found washers that barely fit inside the conduit inner diameter with the bolt size i use. I used the washer as guide to drill hole in end caps, then i stick end cap on the conduit with bolt inside sticking out the cap with a washer which keeps the bolt centered in the tube. Then i dropped the batteries in carefully to fill the tube, then at the other end i used another bolt sticking out of the cap with a washer and cone spring. When i stick the 2nd end cap on, it is under sprung pressure pushing the bolt inside the battery.
David I'm a retired Industrial Electrician and I'd like to make a suggestion on your Battery Wire selection. Visit a local Motor Repair shop and purchase the amperage size you need as Motor Lead wire. The Insulation value is much higher allowing the wire to be smaller if so desired.
Wonderful video. Very useful. I would however not put it in a battery box. It's extra money, but more it keeps the heat developed by the battery in the box.
@@InnovativeSustainableSolutions if u copy him it shouldnt take u any longer than that, its not that complicated or a time consuming task, unless u are not familiar with all the basics of what he did to begin with, then it may take u some time. If u are someone like me that is always messing with these types of things then it should actually take less time, its all about proper prep. Proper prep is one of the most important steps, and ultimately what saves u time. I usually write up steps and everything i need on white board, and layout everything according to my steps.This guy did all the layout and figuring out everything to do. Ur part is basically just assembly, The way I approach things is get everything together tools materals and lay them out in as needed order where possible, battery case on end, say 30 or so minutes getting everything rdy lay out ur cells and put them together that isnt a long process cut materials to length spot weld on etc.. Its easy to see what took him so long, there are a lot of extra problems to solve along with how to do the battery for video. I find most people over think most things and make it harder for themselves.
I perceive those tools to have been investments in various other projects along the way. Not many folks start with all the tools, but planning to acquire one new tool as part of my budget for each new project pays dividends for years to come! Remember to buy good tools-buy once cry once is a key learning. In many cases friends or work pals will not only lend you tools, but better, lend you their experience teaching tool best practices (keeping you from breaking their tools accidentally lol!) often for the cost of a six pack of a preferred cold beverage to be enjoyed together post-assembly! Build tool equity! Fantastic video-thank you for your time in making it David!
Nice Build :) ! One thing, you should put cardboard/paper protection behind your folded positive tab, between this and the cell case, you only have the cell wrap... if this rub out, this will short all the most positive cells ! :/ (cell case/body is negative)
I like this video (although already 2 years old) because I learned a lot, esp. what are the weak points which are not really mentioned: - How to protect against short circuiting when attaching the BMS - Design flaws: the "prepared" end nickel construction (shown at 16:00) has only ONE 8mm strip to combine the two left and right sided cell strings and those can easily provide 20 amps each, but you said that the strip is good for 5 amps only. That is a severe heating source! - Not repair-friendly: welding 20 cells makes it very hard to find broken ones and to replace them - Disassembling the whole thing will bend the nickel stripes again with a high risk of breaking them. Another kind of connection between the 4 blocks of batteries would be nice - Using soldering on critical summarisation points for current on nickel stripes which can heat up is forbidden. The solder can melt and disconnect. Why not welding those as well? - More information about the welding hardware would be desirable - and lots more ... Still a great DIY video! Thx a lot!
Nice work David but one concern I have is that you can actually buy LifePo4-batteries from sources like AliExpress that have 200 Ah with a build in BMS from a reputable source for a similar price. Also if you work with multiple cells you should explain people that it is best practice to bottomlevel(or how it is correctly named , don't remember the exact term) these cells. This is achieved most easiest by placing all cells with the negative pole on a metal plate and putting a metal plate on top of the positive poles. This way you create one giant parallel connection which will result in leveling out the small differences in charge. This will significantly extend the life of the single cells when they are seriesconnected. No cell will 'work' harder than another. One last thing, if you purchase an MMPT-inverter then things like overcharge/temperaturecontrol and sofort are all regulated by that inverter resulting in a very easy installmentprocess. It will srill require some correct programming of the MMPT ofcourse. It has to know what is connected to it(batterychemistry/charge-Amps etc.)
Yeah I discovered that feature years ago when I took at look at them and said, Hmm, I wonder what these do? It's been love ever since! So handy! Just be sure to never threw the screw in accidentally from the incorrect side because if the cut-off side without the head comes out of the threaded side you will without the benefit of a head to use a standard driver on find it harder to have to remove the tail with locking pliers, just a warning...
I learned something valuable too... I always put a nut on and cut it with angle grinder then sand and clean burr and remove nut. How dumb when I have these. Thanks for the knowledge
I loved that too! I always put a nut on the bolt pre cut and by winding it off the bolt you rethread the thread, if that makes sense. It does work, but this is so much better! And cleaner too.
A better tip when assembling a pack is checking all the cell voltages before assembling, and writing down the voltage on the cells. Then, do your best to average the cell voltages used across all parallel packs to get a more balanced starting point. This is why your initial balancing was poor. It will correct itself over time, which will require discharge to ~10%, and then charge to full. Balancing happens once certain cells hit over voltage, and others don't.
Enjoyed the video, Well done! Major concern is your positive lead strip is pressed right up on the batteries. to those building batteries, remember the outer casing of the batteries are the - Negative side. if that thin plastic wears through those batteries will short to your positive lead. I would have used the paper there for sure!! The thin plastic on batteries is just heat shrink plastic and can wear through or even split easily.
The cells having a snug fit not always a good thing. Snug means heat may not dissipate as well as may need to. Lock tight can prevent an electric connection. No issue on the nuts of the circuit breaker as the threads of the bolt do not have high amperage, but the bolts into the case (for Battery Plus and Minus), adding lock tight could keep the bolt from conducting, meaning only the nut of the bolt is conductive (and possible HEAT issues). In some battery cases, the top of the threaded area does not have a large area as it depends on the bolt threads that you've now insulated with lock tight. Have you considered mounting the voltage/amperage gauge inside the battery case (would it/could it fit)? Maybe so if you have several of these tied together, you can see the stats of each pack at a glance. Also, the phone app you are using let you have several BMS units programmed in? If one was to make a larger battery from your battery packs (say 48v), you might want to see each of the 4 BMS units on it's own. Just bought some 5000 cells from Battery hookup, the day after it shipped, these became available. Damn, I wish I had waited just a couple of days, as these look like much better cells then the Lithium-Ion cells I had bought, and are cheaper.
I would tend to agree with the loctite, it does insulate, a star washer would have been a better proposition. On the bms, you could just build up a 48V battery pack and use the appropriate BMS, If you want to use multiple batteries there are other BMS that support daisy chaining. With the electronic advances on BT and so one the possibilities have become pretty much endles for us makers. On the meters, don't know if there was enough space inside the case anymore, but also a good idea, one would need to source a low profile style meter to put in there, I suppose ones imagination is the limit on a build such as this, and what you really need or don't influences the BoM. Nice catch on the loctite though did not even think about that till I read your comment.
The b- and b+ wire was solded on one end of the busbar instead of evenly distrubuted. I saw your previous video doing so with double copper wire as busbar but not this time
I'm very concerned that you (unintentionally) actually went out of your way to restrict airflow around components, including heavy current carrying wires. As a (retired) space craft test specialist (and occasional assembly), I had an even tougher heat dissipation environment in that I didn't even have air convection cooling, just IR radiation, (contact) conduction and heat pipes, so standard practice was to derate 50% -- a 20amp wire can only carry 10amps -- and use the highest temp materials available (teflon wire insulation). We had a new tech run a bundle of wires (teflon insulated and running 50% current) from the heat lamp rack to the vacuum chamber power feedthrough terminal block, and he mistakenly wrapped it in space (reflective) blankets "to protect it from the cold (-270degC) shroud walls" (they don't need protection). Unfortunately, when the air was pumped out, the reflective wrap acted like a thermos bottle! Teflon insulation melts around 800degC so the breakers tripped and the test specimen was destroyed by liquid nitrogen temperatures before we could purge the shroud! What concerns me is that you completely surrounded your power wires in insulating (cutting board) material, preventing any airflow there, where you don't have a temperature sensor. Also, I would provide for battery cooling in the form of a thermostatically controlled fan and ventilation holes. A slightly larger box would be required, of course.
Tesla car battery banks have liquid cooling tubes. Their batteries have had some catastrophic fires when they didn't have the cooling working. There have been fires caused from lithium batteries that have burned property, etc. There is rumored to be a video of a cellphone catching fire in someone's pocket, presumably caused by the battery. I've had some cellphones get very hot while charging in some situations also.
@@MarcMallary I had a quick charger for my 4aa batteries. It somehow failed and burned up. Good thing I was near to stop it right away, or the house would have been a disaster. The house filled up with so much acrid smoke it was unbelievable. It took many hours of using big fans to get it out of the house.
For the version on the Pixel 3, it's probably Android 11 if you don't ignore the updates. If you need to confirm, open the Settings app, go to About Phone, and the Android Version should be 11. Hope that helps if you need it.
$440 on EBAY....brand new...free shipping... 4-5 days maybe for delivery... and you did not have to buy all the tools... but NICE JOB DAVID!!! Very impressed with the build.
I've never heard of this battery material, this battery format, or indeed seen a batttery like that before, so I presume this is for farming equipment or something, judging from the gargantuan box the batteries are going in to. I'm not about to carry a box bigger than a truck battery to charge my palm pilot.
@@InservioLetum This is clearly for solar or offgrid applications (whether mobile in an RV/vehicle or stationary at a campsite, cabin or homesite) and its actually about the size of a truck battery.
Idk about per day but a 100ah 12v lithium battery costs at least twice what he spent in parts to build this and it wont have any built in circuit protection like his battery does.
10:57 You needn't have put the kapton tape, nor the insulating fish paper on those ends of the cells as you're folding them together, which means actually, if they touch, that's going to be better for your series joins as the nickel will be touching each other from the negative of one cell to the positive of the other (in series).... as long as the pack it taped tightly together, you don't need all that insulation and kapton tape. You should probably have some circular/ring positive cell protectors on those cells though, to make it safer. Also, where you fold over that nickel from the positive side, you've got nothing preventing that nickel, after time and with vibrations, rubbing away at the cell's thin plastic shrink wrap and having a direct short from the + of that cell to the - !! Dangerous!
There are a lot of people who are really excited to put up videos about how they did things the first time, without any long term testing. Really, this one only got through a few low-load tests, before he published. Few ever do the follow up video where their cool project caught fire. Or if they even bother, it isn't linked from the first, so people keep building exactly the same deathtrap. Sometimes I comment on videos, and go looking for the aftermaths. That's not just about him. I've never seen his videos before, this just happened to come up. There are others who get very lucky that they didn't die making their cool and exciting videos. Like someone, who won't be named, filling soda bottles with liquid propane and butane, and then exposing them to open flames. Sure, it looked great for the video, but someone's going to get really hurt doing the same, because they think it's safe. I hope there aren't too many people that are hurt or have property loss when their replication of this video fail. Imagine someone putting this kind of battery in their car, or off-grid RV. A few months or years on the road, and your short event is almost guaranteed. One shorted cell fire will cascade into all the cells, and then all the batteries built like this one. No BMS will mitigate that. Even just an overheat event with an ignition source can do it. The short and sparks from that short would do it in.
Great build! It's obvious you have a lot of experience. Two suggestions (nitpicks?), from my experience. One, is that I'd go ahead and solder those crimped terminals. I mostly trust crimped on low current, but for peace of mind I go with solder whenever it involves a high current connection. Two, excessive heat can greatly reduce efficiency. the controller will get hot, but so can the batteries themselves. You have them bundled up pretty tight, I'd consider finding a way to improve air circulation to them as well. Small opening in the case could make a world of diff to the whole thing. If it were mine, I'd probably even squeeze in a small laptop fan. Once again, great build, well presented, enjoyed the video.
Soldered connections with stranded wire are less reliable if subject to vibration. If the battery was to be used in a vehicle I would try to make good crimps only.
I would put paper under where the positive connection is folded against the cells. This is because you only have the plastic coating on the cells preventing a short to the metal cans which are negative.
*...not much Energy, not power.* New LiFePO4 will start 10-15% over and will gain a bit of capacity in the first cycles before capacity starts to fall off as they age. I enjoyed the build!
Of coarse the phone shows a more accurate wattage, it communicates with the BMS via Bluetooth. The other Meter has resistance of the 20-22 gauge wire before it gets its information.
i got 110Amh battery (lead acid) for i think it was 50€ that was used for 1 year in car, and was 2.5 years old so i dont see a point in building this.. even jump starter packs are cheaper and i can take them anywhere (for camping, etc.)
Clickbait my ass... Now I dunno how he got the 500 a day things but... I've been watching a lot of RV videos because I'm about to go live in one full time. And wow, there's a lotta people already living full time in RV's. Those Lithium Ion car batteries are shockingly EXPENSIVE (to me anyway) The RV'ers who are putting in Solar systems -are buying 2 to 4 of those kinda batteries and they cost $1000/$1200 EACH. (I know -right?) Crazy.
Lithium, Iron, Phosphate or other additives are like classes of batteries. Batteries are mostly carbons or coals. They have an in and out design (in and out connected) for discharge, charge, as well as output and return.
"I like." (it). I like saving tons of money by buying savvily things I do not really need (or even want) every day, and that's the secret on how I end up saving 500$ a day, thank you :)
I asked him a couple questions not having the patience to watch. I'm usually the guy that'll watch all of anything I've decided to watch . . .but this was a random click for me . . . Sigh. I think I just suck now for asking him questions without having more patience.
Please put some kapton tap under that positive nickle folded over. The whole cell is negative under that and the heat-shrink on the cells is very thin! Guess how I know this is needed!
David, I'm a BIG fan of DIY and have built my own dual-tracker solar system to power a great deal of my house. I'm putting a system together now to do the same for my garage and its power tools. I note the batteries you're using in your presentation are priced at $3.25 ea (according to the "Battery Hookup" AD for your DIY project to build a 100AH battery). So - that box of 100 such batteries you purchased cost $325.00 not including tax and shipping - unless you managed a "deal" with the supplier - not in evidence here. I can purchase a commercially produced Sigmas Tek SP 12V 100AH battery at retail for $133.00 (not including tax + shipping). I personally can't see the advantage of building your own battery with costs like that. John
John you must not be aware of the difference between the lead acid Sigmas Tek SP battery you spoke of and this battery. A low quality sealed lead acid non spillage battery costing about 145$ discharged by 80% will have a cycle life of 500-1200 cycles and last a maximum of 6 years at which time they will be completely depleted. Most lead-acid batteries experience significantly reduced cycle life if they are discharged below 50%. This means you can only receive 50% of the maximum capacity from the battery without doing damage to it. Every time you discharge a battery of this type beyond 80% you will decrease the cycle life and expected maximum life drastically and severely damage the battery. Cycling this chemistry to 100% discharge you can expect to kill the battery outright in only a few excursions. I did so with 4 fully charged batteries that were 4 years old a total of 5 times after which 3 of the batteries became shorted internally. To safely use this battery type and receive 100AH of usable power from them you would need to purchase and use two 100Ah batteries. The batteries used in this build are lithium iron phosphate batteries and a 12v 100Ah pack similar in form-factor to a single lead acid battery can be commercially bought for 325-750$ depending on quality. These batteries will have a cycle life of 1000-10000 cycles and last beyond 10 years at which time they will retain 70% of their initial maximum capacity if cycled to 80% discharge when used. You can discharge these batteries 100% without risk of ending their life immediately which means you can use up to 100% of the rated capacity of the battery without doing life ending damage to it. It's recommended to not discharge this battery type beyond 80% if you want to reach the rated cycle life. To put it another way, you would need 2X the capacity of lead acid batteries (200AH) to reach a maximum 1200 cycles or 6 years of use, and need only one lithium iron phosphate battery (100AH) to reach a maximum 10000 cycles or 10 years of use. At this rate you could fully discharge the lead acid batteries once every 2 days or discharge the LiPO battery 3 times a day. The lithium battery can handle 6x the charge discharge cycles at a greater discharge amount and last nearly 2 times longer. 80 batteries were used in this video at a cost of $2.93 each costing 234$, not 100 batteries at a cost of $3.25 each. See 41:27 for a cost breakdown. Prices change over time. New larger battery packs are available for LiPO chemistry that reduces the number of cells needed to build a 100Ah pack to as few as 4 cells vs 80 shown in this video. In my experience both battery types mentioned above can fail much quicker than the advertised expected lifespan but by far the lead acid battery can be expected to fail prematurely.
@@btwbrand What’s the good deal these days? I’m looking for some lithium. Might go the route in the video or Chinese cells though ordering from China will take long time
@john Hudson Pretty much in short, the battery you mentioned should only be discharged by 50% or less which means you can only use 50% capacity. So multiply your battery by 2 to get comparable capacity to the battery in the video. Lithium’s also last longer
awesome build video, thanks for sharing! I've been wanting to do this type of project for a while and it's nice to see all the steps laid out. The biggest concern i had was at 12:54 where you folded over the bare metal positive onto the cells. I believe the cell housing is also the negative terminal of the cell. That means the cell insulation is the only thing preventing short circuit and fire. Personally I would put some more paper and tape to make sure there's never an issue there. Maybe you did it off camera or i missed it . I hope your battery doesn't see much vibration and stays intact! also, for those cutting threads, it's a good idea to first put a nut or 2 on your bolt. This way you can file down a taper after cutting the bolt, and any damage remaining on the threads will be repaired by the nut when you remove it. Usually you don't have too much of an issue, but adding the taper is helpful for starting the threads, especially in hard to reach places.
I posted a follow up video where I answered the top 10 questions. One of those was the positive terminal. I took it apart and added more insulation. Good catch.
@@DavidPozEnergy I'm glad you got that before it became a big problem. Awesome battery, it's a shame Battery hookup want twice the price of cells to post to Australia.
All in all, a nice presentation. Thanks. @39:48 For brand new LiFePo4 batteries, the pack series sure seems unbalanced: 161mV min>max. It would have been interesting to see what their individual cell capacities were, prior to assembly. Never used lithium-iron phosphate cells myself, so am unsure how matched they should be, out of the box. That way you could have used Repackr to arrange the battery cells, into each string, & balance out each 1S string, to minimise capacity discharge inequity. Which is what DIYer's do, when using repurposed Li-ion cells. Just for reference, I built a portable Li-ion 3S72P battery, from used laptop batteries, & it gets to 105-125mV separation. Never tested it to full DOD yet, as the inverter does not allow it, due to VDC discrepancy. I do like your videos though, David.
For what is the insulation paper between anyway connected positive and negative poles? Why no additional insulation rings (fish paper) on the plus poles are used? Why use such a expensive spot welder with overheating problems,when the much cheaper cx4500 does the job without cooling brakes?
@Sky Man while six gauge wire would be better if he was matching his wire size to the size of wire on the BMS. You will also notice that there are two 10-gauge wires each can handle up to 30 amps at ten feet without a 3% voltage drop so they should be able to handle 25 amps at less than a foot just fine
While I will agree the title probably should have read save $500 today when you Diy your own battery as while he did play it safe with this battery and making it only pulling 50 amps if you doubled or tripled up on the nickel strips you could pull more than a hundred amps which would mean that this battery that cost less than $500 would be equivalent to a brand of battery which cost $1,000 and has the same capacity
Of course they are over capacity cells! Remember, you ordered 65mm tall cells and they used 70mm tall cells. That gives the cells 7% more capacity right off the bat. Although it makes them useless to most folks spec'ing 65mm cells for specific sizing.
Nope. The extra 5mm comes from the protection circuit soldered to each cell. The cell itself is 65mm, and has the same capacity without the protection circuit.
Top 10 Questions Answered here: ruclips.net/video/sPZwL1z_qxI/видео.html
How do you know that small wires inside can hold current from the batteries?
David...this is an awesome project, but u definitely know what u r doing in regards to DC currents and voltages etc and the use of meters, heating etc, what is your background, are u a technician...thks..i would love to try that set up but not understanding the principles of DC electricity, one could harm himself..thks
thanks a bunch for this quick response
Wifey wants her iPhone back...
Can I buy that battery from you? I have a back injury at the moment and can't get around to do much. I am living on my sailboat in Seabrook Texas and need a decent power supply. I would appreciate it. If you aren't using it that is?
Just spent 40min watching a guy build a battery. Intriguing and fascinating. Learned a lot.
I’ll just buy one.
i only missed the part where you can save 500/day :D
i know right
Lol indeed
Should these even be put in a car? 🤣
I Need to start spending $500/day so I can start saving $500/day!
It cost him $ 440, less his labour, a battery that spec, worth 900 to 1100 k, so ill assume he means, he saved 500, if he sells them for 900,he made 500,for that day project, but he should say this , tp not look click baitish
SON! probably the best presentation of any subject I have watched on u'tube! I've been to automotive and aircraft schools off and on over the 55 years in the mechanical field. I had only a couple of instructors that presented the info as concise as your did, and that's including speech delivery, clear! Thanks!
Its people like you that make youtube a great place. I know people come to youtube for different reasons, some purely entertainment, some news, I do sometimes for those reasons also. My biggest reason for coming to youtube and spending countless hours on it, is to learn from people like you, it has allowed me and millions of people around the world to watch great videos like this to learn new things that otherwise we would be clueless about. Thx for the video and clear explanations and I wish u the best in 2021!
Your welcome. Thanks for checking it out, and the kind comment.
Thank you David, alot people make comments that just rediculous and waste of time to say, instead of being appreciative of knowledge you share and time given to share with others. So thank you.
One of the best vids on you tube. No over explanations, no poxy music in the background, well done.
I didn't realize that, but you're spot on! Really well put together indeed.
For increased cell life, you don't want to use 100% of the capacity. The peak and valley of the charge curve cause the most wear on the cells. So if you trim 5-10% off the top and bottom you get extended life. So if the cells will go as high as 3.65, trim that to 3.6 and if the bottom is 2.8, maybe bring that up to 2.9 or even 3.0v. You would still use 80-90% of the capacity, but you'd get another couple years of use out of those cells.
The profile to set the top and bottom cutoff needs to be an option within the BMS - does the BMS David installed have this capability?
I'm sure you already know this but cells with built in battery protection circuits tend to be longer, even though they can be marked as 18650. Some of these circuits can add 5mm to the length and this may be why. If you rip the plastic wrapper off one, you might find one tacked onto the end of a cell.
Awesome thing to build your own battery David! Amazing what you have learned about all this stuff because you were not afraid to try. Your kids are also watching and learning. They'll be awesome as well. You and your wife are great parents.
For the amperage you intend to pull, I strongly suggest you refold your positive terminals in the other direction, as the outside of the battery cells are actually negative if and and the insulations get damaged, so with the potential heat in real use, folding your positive wires to not touch or be in close proximity to the side wall seems to be a safer choice.
Exactly my thoughts! I really hope he had some sort of insulation in there behind the bus bar...
I was waiting for one of the solder blobs to go through the cell sleeve and arc out.
I like how you suggest he fold it as opposed to just not using wide open huge rails. smaller rails, rails snapped into the structure, COVERED... nope! fold it the other way. that's worth the time!
Greetings from Russia David! I would advise you to charge the battery with a balanced charger, bypassing bms, and entrust the board only with a protective shutdown. I do not trust balancing to these boards (my personal humble opinion), and balancing is not needed every time if the cells are new and from the same batch. Good luck with your projects!
True!
How do you use a balanced charger with only two connectors? Wouldn't you need an additional connector after each "row" of batteries?
Agree.
I'm liking these cells and the battery box... if you did 80 cells in the box and you did a 48v battery 16s5p you could make a nice 25ah battery for your 48 volt inverter. All you need is a 16s bms.
Good point! I wonder what configuration / layout would work best for that box?
I am given to understand that some BMS units can work in series with others of the same or similar BMS type, so you could actually build several batteries of 12V 25AH and put them in series for either 12, 24, 36, 48, 60, or 72 volts. But check very carefully that the BMS is rated for the maximum voltage configuration!
wow man i have never seen such a detailed build, most people will stop after the spot welding, but that final parts cost sheet is the icing on the cake.
Thanks for watching to the end.
I can't believe I forgot about this diy favorite of mine from way back with the salvage car hybrid battery buid for the garage/house power bank. Or the test and trial of finding the right power inverter the solar panels and solar water heater system that was built. Man ,now finding the latest Lytham 14 volt clean diy .. nice! Ty Dave p.
Thanks for the great information. Might I suggest a diagram showing your circuit layout before you begin... It might help us older guys who learned everything reading manuals. Lol. Thanks again..
Good project bud, that's not a bad value for the battery with knowing what's inside. I recently bought a premade lithium battery from amazon that was suppose to be a drop in replacement for my motorcycle, received it and it felt very heavy for a lithium battery, pulled it apart to find it was made up of used 18650 cells with 4 different model cells in use inside and had no internal bms at all, just lots of snot covering everything to keep everything glued together.
I was going to buy one and once I saw the prices I laughed my ass off. It's bad enough the raping they do to you for a damn lead acid bike battery and I've always hated buying them so since I have piles and piles of 18650's and use them for everything I just put 2p3s together and wrapped it with some black tape, soldered it together with some 12 guage. You do know everyone says you can't solder them right? Bullshit I've soldered thousands of these things and never once had one go bad and I'm not very good with this piece of crap gun I've got and most times the battery is beyond hot and can't be touched and I've never had a problem. So I just wanted to see if it would power my klr 650 and do what it needs and it was more than enough. Considering that 18650's are free everywhere all day long you don't need a bms. I've left these things on for months in the rain, snow, in the dirt and they were most surely dead and they charge right back up everytime. Almost every single thing they ever told us about Lithium is pure lies my friend and if anyone was going to have one blow up it would have been me since I've always tried but to no avail so all I can say is you could make yourself a backup battery for about NOTHING and just get a charger circuit for 12 bucks so you can use lipo instead of lifepo and your alternator can easily handle your electricity needs. If you replace some bulbs with Led their is no reason to buy the real thing. If you truly fill the whole battery space your bike has you'll have way more than enough power and you'll never get a dead battery from flooding it or a fouled plug and that to me is so much better than lead acid since you should know if you take one below 10 volts you basically guarantee it won't be there for you when you truly need or want it as is the character of L/A junk. Bms are for suckers or large expensive projects, you could probably start your bike with just 3 18650's!! Try it if you don't believe me, wouldn't take you more than 10 minutes to make one up and see for yourself and in case you're wondering what I meant by free just t hink recycle, that is where the proven ones are with one dead cell among them and in my experience they defy all the myths the internet is full of.
Peace
Sizzlean
You get what you pay for
@@sizzlean9459 : lol, just don't park, charge, or wreck it where it will burn down a house or start a forest fire.
BMS aren't really necessary. They help squeeze out that extra little bit of energy in a battery without damaging it.
The 5 extra millimeters of size on you LiPo batteries is from the protection circuitry, you can see it as that extra wafer size on the positive anode.
Yes. He should check the specs to find out what the max sustained current draw is.
dont talk if you dont know what you are talking about...
Only because they look like protected cells doesnt mean they are. And in fact, they ARE NOT PROTECTED.
When cells wear down they will eventually fail. Either as a short or open connection, however the later condition is rare.
In other words. This battery has 80 points of possible failure!
IMHO you should have used some "nickel-strip" with built-in fuses to avoid setting your house on fire.
Good call. Expensive, industrial grade packs cut slits in the nickel strip to create "fusable links". If a cell shorts and exceeds a certain current, the strip burns away and the cell is isolated. I haven't yet seen a DIY battery project video where the author does this. It would be interesting to see what the chances of such a failure are.
Solid Build!!
Only critique I have is at @12:52. When you bend your busbar back, it's now in a place where it can rub on the can. Since the can is negative, if you use this battery in a mobile application, you have created a fire risk when the bar rubs through the cell's original insulation. Some of the battery paper, maybe 2 layers, would help that a lot.
Thanks. I fixed that in the follow up video.
Whoa, whoa, whoa. Weren't you going to compare this to buying an off the shelf equivalent? So yours cost $440 to build and you limited it to 12.9V @50A. So what off the shelf unit of that same output are you comparing it to and how does this save you over $500? And for that matter, how is it "$500/day"? Is there an ATM included?
his angle is affiliate sales, exactly..you save about a hundred bucks it seems.
It occurs to me that these are questions that the content provider would want to put to bed right away. Somewhat disappointing to see that they have gone unaddressed.
@@61JWolf True, l agree.. however most providers would've removed this negative comment thread which is still here.
Have a good one.
Ciao...!
You save $500 by not spending any money.
When this video was released almost 4 years ago a 12v 100Ah was around $1000, a year earlier $1500. Now you can get them for as low as $250 so this content not so applicable today as the prices of the 32650(32700) haven't dropped inline with larger cells.
So, imo, the $500/Day is fairly accurate for the time. $500 savings and approximately a day to build.
The 50 amp limit was a personal choice and once again, imo, a good one. My whole house doesn't run 50 amps with everything turned on.....for 50 amp loads you are wanting a much larger battery!!!!!
Great video.
You need tape between your positive terminal and the side of your battery, which is negative. A tiny bit of rubbing and you will dead short the positive of those 20 cells to the negative of those 20 cells. A couple layers of tape and some insulating board is needed or this will one day become a bomb.
To clarify for Dave, Ecospider5 is talking about the bit at 12:55 ish where the nickel strip for the positive terminal is folded around to the side of the cells. Here the heatshink around the cells is a potential point of failure. If the strip were not folded over like that there wouldn't be an issue.
I was going to post a comment about this. This is very critical, since the nickel strip sharp edge could easily cut into the battery shrink wrap. I would try to fix this sooner rather than later. Other than that great build.
Glad someone else spotted and reported that too! I ringed when the loaded case was manhandled over on the bench :)
I said the same. Not sure he's reading these comments though but I hope he is or he'll have a very nasty fire some day.
Your positive bus bar is resting up against the sides of the cells which will cause a short if it wears through the cell wraps. You should put kapton tape and/or sticky paper.
That's a good point, thanks.
Heat, vibrations or time, would do that. That's logical thinking @11mlger.
Well done I use to install solar systems in the 80s we used lead acid fork lift battery's. The battery banks were usually only 48 volt systems so there was not a hazard from getting shocked but a short across a battery battery bank will do severe damage to anything near by. Take every precaution to not let the positive and negative leads touch the amperage is very height and will weld and or vaporize conductors.
Nice and clean build ,, also great video without saying bla bla bla and wasting our time
Mind blown I had to immediately check my wire strippers and have the same screw cutting feature I had no clue existed. Thanks for that tip!!!
Thanks for the tips, man! My $1000/day battery habit was starting to get out of control!! ✊😅💜
Same, I'm a bit more of an extremist. This end up saving me $800 a day.
Three years ago I had to replace the 1.5 KWH house battery bank in my sailboat. I looked at Lithium batteries and the price worked out to about $1800, so I replaced the old lead-acid batteries with... new lead acid batteries for about $600 (6 T105's from Sam's Club).
If this build can hit 1500 WH for $400 My next replacement will (finally) be lithium. It looks like the build is 1/3 smaller than the lead acid bank so I could (finally again) put in a larger bank Putting it together gives me something to do when it's not sailing season ;=) . Looks like we've rounded a corner regarding price.
Thanks for a complete and highly informative vid.
Crappy part about the lead acids is they seem to start dying within 6 months to a year even if you rarely use them. You shouldn't notice any degrade for at least 3-5 years with a lithium when rarely used.
You only get 50% out of the lead acids, if they're in good shape.
I would have put in an active balancer, I had the same issue of High voltage disconnect, and an active balancer solved this issue. Now getting full charge in quicker
I was a diesel mechanic and my first job was to fix electrical problems occuring in the fleet and I used the screw cutting feature of my wire crimper quite a lot as the stockroom only carried these in 2" lenght. After a few dozen screws, the crimper joint gets loose, the cut is not as straight and the screw is hard to remove. You have to reset the rivet on the crimper.
I'm not yet ready to swap my 12 golf cart batteries for Lithium batteries but I would DIY a few if I needed to start from scratch.
Nice video with a lot of info, trics and tips. Thanks DavidPoz and take care.
Thanks for sharing your experience. Good to know.
You make it easy to understand and follow along thank you
This is a somewhat unsafe battery. Timestamps to where build mistakes were made.
11:08 round your positive corners you madman. No fishpaper rings either. Sure it takes an extra $10 and 30min, but it's worth it for the peace of mind.
12:54, you folded a positive line over the negative casing of the battery. Meaning that thin pvc shrink the batteries are housed in is the only thing preventing a dead short. Put some fishpaper between them.
15:56 should be discharging from both "corners" it's fine I guess, but not ideal when you could have easily soldered the wires on each.
When charging to make perfect balance. Set power supply to slightly less than the balance current of the bms. (Usually 100mv) this allows the bms to burn off the high cells at the same rate of charging so no overvoltage cutoff will happen while balancing.
THIS I came here to say you folded the positive onto the casing of the battery. Any vibration and it'll wear through and short out
Did you meant to say 100mA?
@mike h So the internal heating and cooling of the cells will not make them expand at all? And you are willing to bet your house on that? .... you know that no insurance will pay up on a self built battery fire ;0)
If you want to see battery packs igniting look up Louis Rossman ...... different battery type but still the same reaction!
Seems like you know how to ride stuff and that's about it........ Where are your battery builds? And calling someone a mad man just 'cause you think you know better? Juvenile! Very Juvenile.
@@totherarf the parralel configuration can handel 100A as calculated he because of the BMS setup and the DC braker can't draw more than 50A. Those cells can handel 20A constant he is only going to draw half that when fully loaded. After that, the DC braker or the BMS will shut down. Unless those batteries are drawn up to full capacity there should be no swelling of the cells. So please tell me, why the scare tactics? We all know how dangerous these batteries can be, but you completly overlooked all the safty measures that David took.
I love the detailed step by step planning and assembly. Absolutely professional
For me it does not look professional due to some severe points missing:
- How to protect against short circuiting when attaching the bms
- Design flaws: the "prepared" end nickel construction has only the 8mm strips to combine the two left and right sided cell strings and those can easily provide 20 amps each, but you told us the strip is good for 5 amps. That is a severe heating source!
- Not repair-friendly: welding 20 cells makes them very hard to find broken ones and to replace them
- The welding points can heat up
- More information about the welding hardware would be desirable
- and lots more
I never realised you could cut bolts with those pliers, I thought you only used them to check threads. Thanks for showing that.
Agreed I’ve always just checked threads for enclosures on them lol.
that makes 3 of us, my friends.
that is cool
Not very good with #10 SS!!!
Wtf - same here.
Thanks for taking the time to video this project. New subscriber thumbs up. Cheers
Greit job, thank's for taking your time to make a video, about how you did it.
I loved every minute of this! This is exactly how my mind works, so it's not 'work' at all. It's challenging, exciting, and makes me want to get back to being inventive and creative. I'm also eternally thankful to my ancestors for their contributions to my DNA. I know my gifts and shortcomings, and as I age, my ability to handle disappointments has improved dramatically.
Most all you guys and possibly some females know exactly what I'm saying! I love all of you as I love myself. I wish the very best to you all!!!
What a weird, masturbatory comment. You seem inadequate.
You know honestly I don’t remember the last time I have watched a 30min+ video but man I have really enjoyed yours
I don’t own a solar panel, I don’t know the first thing about electricity or batteries but I have really enjoyed it
Keep it up 👍🏼
Love from Syria 🇸🇾
Same here. I know very little about these topics but he made it really interesting to learn.
The great thing is you can learn so much from his videos and the other guy (j-who) that you can start making your own battery packs. If you teach yourself basic electrical how electicity flows fom positive to negative and how to add voltage and amperage depending on serial or parallel circuits, you can learn to do everything this guy is doing for yourself and.configure batteries in way that meet your own exact needs. It's not as hard as some people think. One day as a kid, I learned electronics using an old RadioShack 100 in 1 electronic experiments set. Now I'm an adult and thanks to the encouragement from RUclips am finding ways to creatively adapt an changing out the types of batteries various goods around the house use for 18650 packs because the limited battery types of 9V, AA, AAA, and C size conventional batteries annoyed me so much with their short lives and constant recharging or replacement. Its easier than you think. It just takes a little determination to learn what's necessary to figure things out. With RUclips, you can litterally teach yourself anything that isn't a corporate secret.
Just an idea.
To avoid heating up the batteries with the soldering iron, solder the wire from the balancing lead to a small piece of nickel strip, then spot weld that piece to the battery terminal.
Really appreciate your attention to detail. However for me it’s more educational than practical. I don’t think I’d have the same confidence in my ability. I am sure there are viewers who could DIY this but not for me. Too many ways this could go south. As they say I have just enough knowledge to be dangerous 😀
No problem. This video is over a year old, and there are many more options on the market today. I'd buy this one instead of DIY today: signaturesolar.com/eg4-wp-lithium-battery-12v-100ahs/?ref=4_rHcgZ9x-TiF-
Back when I was filming this the 12V, 100Ah, batteries on the market were about $900+.
ONE HUNDRED EIGHTY THOUSAND DOLLARS A YEAR - FREE
$500 a day, for a year you'll SAVE $182,500.00? RIGHT ?
At 76, I live off grid with solar and lithium. We NEED more of it. We NEED folks like you. We DON'T need Click Bait ! !
You have helped to demistify a complex subject, this is a great training video
If you want to charge at 50A then your breaker should be 60A.
Unless you have a 100% rated breaker, you normally have to limit the continuous current through the breaker to 80% or 40A with this 50A breaker.
Instead of adding those spacers to two sides I think it would have been interesting to add thin spacers on all four sides to let a little air vent
People used to rebuild their lead/acid batteries using sheet lead for plates.
You can even recycle the lead and sulphuric acid, if you know what your doing.
Robert Murray Smith did a RUclips video about it.
He got the directions from a book from the 1920's or so.
It might be good knowledge in a post apocalyptic, post industrial, post SHTF time.
Thank You for All that you are doing for World Peace and for our Planet...
Peace.. Shalom.. Salam.. La Paz.. Namaste ..
🙏🏻 😊 🌈 ✌ ☮️ ❤️ 💐 🕊
Ha, I never knew you could cut screws with wire strippers, seen holes just never paid attention to them. Thanks
Same, always wondered what those holes and numbers were for.
Me either and I been using that tool off and on for 30 years lol, amazing you always learn something new from the weirdest of places lol. Loved the video, but have no idea why I watched it all lol, didn't understand half of it but it was fun to watch and made me brain think lol. Have a great day :).
same learned something new haha
@@snoozin99 yeah Hope I can get a metric one here in Thailand hahaha then theres the minor problem of getting some screws Dont come to live in thailand unless you just want to grow mangoes and farm chickens and get old :-(
you should try reading the instructions that came with the strippers some time instead of tossing that paper in the garbage.
Have you ever tried making batteries out of PVC? I recently made some 12v battery sticks as experiment by cutting a section of 3/4 pvc conduit, pvc end caps, bolts, cone springs, and washers. I found washers that barely fit inside the conduit inner diameter with the bolt size i use. I used the washer as guide to drill hole in end caps, then i stick end cap on the conduit with bolt inside sticking out the cap with a washer which keeps the bolt centered in the tube. Then i dropped the batteries in carefully to fill the tube, then at the other end i used another bolt sticking out of the cap with a washer and cone spring. When i stick the 2nd end cap on, it is under sprung pressure pushing the bolt inside the battery.
Whitney punch
Finally a quality Lifepo4 diy batter video! I need to build a 72v version for my ebike
David I'm a retired Industrial Electrician and I'd like to make a suggestion on your Battery Wire selection. Visit a local Motor Repair shop and purchase the amperage size you need as Motor Lead wire. The Insulation value is much higher allowing the wire to be smaller if so desired.
Wonderful video. Very useful. I would however not put it in a battery box. It's extra money, but more it keeps the heat developed by the battery in the box.
"this will take you guys 6 to 8 hours to complete"
That's a good one.
You got it haha :D
6 to 8 hours to complete after you've done it 6 to 8 times already.
Maybe on your second one lol
@@InnovativeSustainableSolutions if u copy him it shouldnt take u any longer than that, its not that complicated or a time consuming task, unless u are not familiar with all the basics of what he did to begin with, then it may take u some time. If u are someone like me that is always messing with these types of things then it should actually take less time, its all about proper prep. Proper prep is one of the most important steps, and ultimately what saves u time. I usually write up steps and everything i need on white board, and layout everything according to my steps.This guy did all the layout and figuring out everything to do. Ur part is basically just assembly, The way I approach things is get everything together tools materals and lay them out in as needed order where possible, battery case on end, say 30 or so minutes getting everything rdy lay out ur cells and put them together that isnt a long process cut materials to length spot weld on etc.. Its easy to see what took him so long, there are a lot of extra problems to solve along with how to do the battery for video. I find most people over think most things and make it harder for themselves.
So how long would that be having to deal with 4 children 24/7 at home from 1yrs old to 6yr old...
Great video. You’re fortunate to have the extra tools ie spot welder, calipers, various meters, and torx wrenches to make this happen at that price.
My thoughts exactly, the moment I saw what he was doing...! Those will simply eat up any savings you might make in building your won batteries.
I perceive those tools to have been investments in various other projects along the way. Not many folks start with all the tools, but planning to acquire one new tool as part of my budget for each new project pays dividends for years to come! Remember to buy good tools-buy once cry once is a key learning. In many cases friends or work pals will not only lend you tools, but better, lend you their experience teaching tool best practices (keeping you from breaking their tools accidentally lol!) often for the cost of a six pack of a preferred cold beverage to be enjoyed together post-assembly! Build tool equity!
Fantastic video-thank you for your time in making it David!
Nice Build :) ! One thing, you should put cardboard/paper protection behind your folded positive tab, between this and the cell case, you only have the cell wrap... if this rub out, this will short all the most positive cells ! :/ (cell case/body is negative)
Thanks for the tip. I'll get in there and do that. I appreciate the comment.
Yes please pin one of these comments to the top so it will be seen by everyone. This is guaranteed to short eventually in it current configuration.
Been on this earth for 42 years and I never knew about the wire stripper 6-32 hack. Mind Blown!
I like this video (although already 2 years old) because I learned a lot, esp. what are the weak points which are not really mentioned:
- How to protect against short circuiting when attaching the BMS
- Design flaws: the "prepared" end nickel construction (shown at 16:00) has only ONE 8mm strip to combine the two left and right sided cell strings and those can easily provide 20 amps each, but you said that the strip is good for 5 amps only. That is a severe heating source!
- Not repair-friendly: welding 20 cells makes it very hard to find broken ones and to replace them
- Disassembling the whole thing will bend the nickel stripes again with a high risk of breaking them. Another kind of connection between the 4 blocks of batteries would be nice
- Using soldering on critical summarisation points for current on nickel stripes which can heat up is forbidden. The solder can melt and disconnect. Why not welding those as well?
- More information about the welding hardware would be desirable
- and lots more ...
Still a great DIY video! Thx a lot!
Nice work David but one concern I have is that you can actually buy LifePo4-batteries from sources like AliExpress that have 200 Ah with a build in BMS from a reputable source for a similar price. Also if you work with multiple cells you should explain people that it is best practice to bottomlevel(or how it is correctly named , don't remember the exact term) these cells. This is achieved most easiest by placing all cells with the negative pole on a metal plate and putting a metal plate on top of the positive poles. This way you create one giant parallel connection which will result in leveling out the small differences in charge. This will significantly extend the life of the single cells when they are seriesconnected. No cell will 'work' harder than another. One last thing, if you purchase an MMPT-inverter then things like overcharge/temperaturecontrol and sofort are all regulated by that inverter resulting in a very easy installmentprocess. It will srill require some correct programming of the MMPT ofcourse. It has to know what is connected to it(batterychemistry/charge-Amps etc.)
Oh wow I really didn't know that wire strippers could do that ! I just checked mine and they have the same bolt choppers lol
Thank you 😂😂😂
Yeah I discovered that feature years ago when I took at look at them and said, Hmm, I wonder what these do? It's been love ever since! So handy! Just be sure to never threw the screw in accidentally from the incorrect side because if the cut-off side without the head comes out of the threaded side you will without the benefit of a head to use a standard driver on find it harder to have to remove the tail with locking pliers, just a warning...
I learned something valuable too... I always put a nut on and cut it with angle grinder then sand and clean burr and remove nut. How dumb when I have these. Thanks for the knowledge
I have been using my wire strippers for YEARS and have just found a new use for them. THANKS! 🤩
I loved that too! I always put a nut on the bolt pre cut and by winding it off the bolt you rethread the thread, if that makes sense. It does work, but this is so much better! And cleaner too.
Dave always has answers!
A better tip when assembling a pack is checking all the cell voltages before assembling, and writing down the voltage on the cells. Then, do your best to average the cell voltages used across all parallel packs to get a more balanced starting point. This is why your initial balancing was poor. It will correct itself over time, which will require discharge to ~10%, and then charge to full. Balancing happens once certain cells hit over voltage, and others don't.
Bro your videos are the dopest
I'm learning so much from you!!!!
Enjoyed the video, Well done!
Major concern is your positive lead strip is pressed right up on the batteries.
to those building batteries, remember the outer casing of the batteries are the - Negative side. if that thin plastic wears through those batteries will short to your positive lead.
I would have used the paper there for sure!!
The thin plastic on batteries is just heat shrink plastic and can wear through or even split easily.
Here I address that concern: ruclips.net/video/sPZwL1z_qxI/видео.html
The cells having a snug fit not always a good thing. Snug means heat may not dissipate as well as may need to.
Lock tight can prevent an electric connection. No issue on the nuts of the circuit breaker as the threads of the bolt do not have high amperage, but the bolts into the case (for Battery Plus and Minus), adding lock tight could keep the bolt from conducting, meaning only the nut of the bolt is conductive (and possible HEAT issues). In some battery cases, the top of the threaded area does not have a large area as it depends on the bolt threads that you've now insulated with lock tight.
Have you considered mounting the voltage/amperage gauge inside the battery case (would it/could it fit)?
Maybe so if you have several of these tied together, you can see the stats of each pack at a glance.
Also, the phone app you are using let you have several BMS units programmed in? If one was to make a larger battery from your battery packs (say 48v), you might want to see each of the 4 BMS units on it's own.
Just bought some 5000 cells from Battery hookup, the day after it shipped, these became available. Damn, I wish I had waited just a couple of days, as these look like much better cells then the Lithium-Ion cells I had bought, and are cheaper.
My first thought was "WTF - he bought 5000 cells? 😱" - then I noticed you've been talking about 5000mAh cells... 🤣
I would tend to agree with the loctite, it does insulate, a star washer would have been a better proposition. On the bms, you could just build up a 48V battery pack and use the appropriate BMS, If you want to use multiple batteries there are other BMS that support daisy chaining. With the electronic advances on BT and so one the possibilities have become pretty much endles for us makers. On the meters, don't know if there was enough space inside the case anymore, but also a good idea, one would need to source a low profile style meter to put in there, I suppose ones imagination is the limit on a build such as this, and what you really need or don't influences the BoM. Nice catch on the loctite though did not even think about that till I read your comment.
😵 @spaRTan3246 I was like whoa! Thanks for the interpretation!
So, how exactly is this gonna save $500 *per day*? Do you destroy one 100Ah-battery every day?
Nah...you build one a day...6-8 hours...you see. (yeah right!)
Lithium batteries have usefull life of around 1000 recharges.
Surely, If you use It with low discgarges currents, Will be more than 1000.
@@edgewood99 Zackly...every day.
@@edgewood99 yea I got that, but what about the hours of work put into it...
this exact battery sells fells for ~$1000 from several different manufacturers. It costs about $500 to build the battery you see here.
Excellent work and you are a great instructor. Thanks for sharing your project.
Impressive!!! Your attention to detail is so good I can see Howie Mandel pop up and say "You can do iiiitttttt." 😃
Thanks for going over this project! I always love learning about your Poz loads.
The b- and b+ wire was solded on one end of the busbar instead of evenly distrubuted. I saw your previous video doing so with double copper wire as busbar but not this time
I'm very concerned that you (unintentionally) actually went out of your way to restrict airflow around components, including heavy current carrying wires.
As a (retired) space craft test specialist (and occasional assembly), I had an even tougher heat dissipation environment in that I didn't even have air convection cooling, just IR radiation, (contact) conduction and heat pipes, so standard practice was to derate 50% -- a 20amp wire can only carry 10amps -- and use the highest temp materials available (teflon wire insulation). We had a new tech run a bundle of wires (teflon insulated and running 50% current) from the heat lamp rack to the vacuum chamber power feedthrough terminal block, and he mistakenly wrapped it in space (reflective) blankets "to protect it from the cold (-270degC) shroud walls" (they don't need protection). Unfortunately, when the air was pumped out, the reflective wrap acted like a thermos bottle! Teflon insulation melts around 800degC so the breakers tripped and the test specimen was destroyed by liquid nitrogen temperatures before we could purge the shroud!
What concerns me is that you completely surrounded your power wires in insulating (cutting board) material, preventing any airflow there, where you don't have a temperature sensor. Also, I would provide for battery cooling in the form of a thermostatically controlled fan and ventilation holes. A slightly larger box would be required, of course.
Tesla car battery banks have liquid cooling tubes.
Their batteries have had some catastrophic fires when they didn't have the cooling working.
There have been fires caused from lithium batteries that have burned property, etc.
There is rumored to be a video of a cellphone catching fire in someone's pocket, presumably caused by the battery.
I've had some cellphones get very hot while charging in some situations also.
@@MarcMallary I had a quick charger for my 4aa batteries. It somehow failed and burned up. Good thing I was near to stop it right away, or the house would have been a disaster. The house filled up with so much acrid smoke it was unbelievable. It took many hours of using big fans to get it out of the house.
For the version on the Pixel 3, it's probably Android 11 if you don't ignore the updates. If you need to confirm, open the Settings app, go to About Phone, and the Android Version should be 11. Hope that helps if you need it.
Could have saved maybe $5.00 (no big deal) by just updating the Android ver.. Apple charges for everything.
$440 on EBAY....brand new...free shipping... 4-5 days maybe for delivery... and you did not have to buy all the tools... but NICE JOB DAVID!!! Very impressed with the build.
Yeah, it's amazing how many more options there are to buy this type of battery in just the last year.
Fastcap marking pens, nice choice. Paul Akers is a lean manufacturing innovator and his company Fastcap is second to none.
I need someone to explain me how exactly I can save 500$ PER day with this.
Diy my ###
I've never heard of this battery material, this battery format, or indeed seen a batttery like that before, so I presume this is for farming equipment or something, judging from the gargantuan box the batteries are going in to. I'm not about to carry a box bigger than a truck battery to charge my palm pilot.
@@InservioLetum This is clearly for solar or offgrid applications (whether mobile in an RV/vehicle or stationary at a campsite, cabin or homesite) and its actually about the size of a truck battery.
Me too.
Idk about per day but a 100ah 12v lithium battery costs at least twice what he spent in parts to build this and it wont have any built in circuit protection like his battery does.
10:57 You needn't have put the kapton tape, nor the insulating fish paper on those ends of the cells as you're folding them together, which means actually, if they touch, that's going to be better for your series joins as the nickel will be touching each other from the negative of one cell to the positive of the other (in series).... as long as the pack it taped tightly together, you don't need all that insulation and kapton tape.
You should probably have some circular/ring positive cell protectors on those cells though, to make it safer.
Also, where you fold over that nickel from the positive side, you've got nothing preventing that nickel, after time and with vibrations, rubbing away at the cell's thin plastic shrink wrap and having a direct short from the + of that cell to the - !! Dangerous!
Was going to say exactly this! That could be very dangerous
There are a lot of people who are really excited to put up videos about how they did things the first time, without any long term testing. Really, this one only got through a few low-load tests, before he published.
Few ever do the follow up video where their cool project caught fire. Or if they even bother, it isn't linked from the first, so people keep building exactly the same deathtrap. Sometimes I comment on videos, and go looking for the aftermaths.
That's not just about him. I've never seen his videos before, this just happened to come up. There are others who get very lucky that they didn't die making their cool and exciting videos. Like someone, who won't be named, filling soda bottles with liquid propane and butane, and then exposing them to open flames. Sure, it looked great for the video, but someone's going to get really hurt doing the same, because they think it's safe.
I hope there aren't too many people that are hurt or have property loss when their replication of this video fail. Imagine someone putting this kind of battery in their car, or off-grid RV. A few months or years on the road, and your short event is almost guaranteed. One shorted cell fire will cascade into all the cells, and then all the batteries built like this one. No BMS will mitigate that. Even just an overheat event with an ignition source can do it. The short and sparks from that short would do it in.
@DavidPoz - Can you reply to the first part of @darkkevind? I am very curious.
H(
Please. Make us a video project to show us.
Great build! It's obvious you have a lot of experience. Two suggestions (nitpicks?), from my experience. One, is that I'd go ahead and solder those crimped terminals. I mostly trust crimped on low current, but for peace of mind I go with solder whenever it involves a high current connection. Two, excessive heat can greatly reduce efficiency. the controller will get hot, but so can the batteries themselves. You have them bundled up pretty tight, I'd consider finding a way to improve air circulation to them as well. Small opening in the case could make a world of diff to the whole thing. If it were mine, I'd probably even squeeze in a small laptop fan. Once again, great build, well presented, enjoyed the video.
Soldered connections with stranded wire are less reliable if subject to vibration. If the battery was to be used in a vehicle I would try to make good crimps only.
I would put paper under where the positive connection is folded against the cells. This is because you only have the plastic coating on the cells preventing a short to the metal cans which are negative.
*...not much Energy, not power.*
New LiFePO4 will start 10-15% over and will gain a bit of capacity in the first cycles before capacity starts to fall off as they age.
I enjoyed the build!
Of coarse the phone shows a more accurate wattage, it communicates with the BMS via Bluetooth. The other Meter has resistance of the 20-22 gauge wire before it gets its information.
WHo is spending $500 every day on batteries, that they have that much to save? clickbait title is clickbait
i got 110Amh battery (lead acid) for i think it was 50€ that was used for 1 year in car, and was 2.5 years old
so i dont see a point in building this.. even jump starter packs are cheaper and i can take them anywhere (for camping, etc.)
Clickbait my ass...
Now I dunno how he got the 500 a day things but... I've been watching a lot of RV videos because I'm about to go live in one full time. And wow, there's a lotta people already living full time in RV's.
Those Lithium Ion car batteries are shockingly EXPENSIVE (to me anyway) The RV'ers who are putting in Solar systems -are buying 2 to 4 of those kinda batteries and they cost $1000/$1200 EACH. (I know -right?) Crazy.
Battle born 1000 A/hr 1000 dollars
@@exvils hook up an inverter and run it for 2400Wh drain that battery down to 10v, and let me know how long it lasts...
Even the most conservative RUclipsrs use clickbait titles, if they don't, they don't get views. On the other hand this one is almost meaningless.
Now all I need to do is add on the cost of the 'Spot Welder', and other necessary tools to accomplish this amazing project. :) :P
Title attracted a different crowd I believe :) IMHO the work is gold and very satisfying
been experimenting with making these but the size of these batteries makes this so much better and reasonable to do! thanks for this video!
Seriously. Years ago I never finished cuz these products didn't exactly exist (although possible to make=more work)
And I just noticed I commented on a old comment of mine that I have no recollection...I've officially lost my mind...smh
Lithium, Iron, Phosphate or other additives are like classes of batteries. Batteries are mostly carbons or coals. They have an in and out design (in and out connected) for discharge, charge, as well as output and return.
"I like." (it). I like saving tons of money by buying savvily things I do not really need (or even want) every day, and that's the secret on how I end up saving 500$ a day, thank you :)
Wow I didn't notice this was a 41 min video, I just finished watching and it was so interesting to watch the entire build, great job
I asked him a couple questions not having the patience to watch. I'm usually the guy that'll watch all of anything I've decided to watch . . .but this was a random click for me . . .
Sigh. I think I just suck now for asking him questions without having more patience.
Please put some kapton tap under that positive nickle folded over. The whole cell is negative under that and the heat-shrink on the cells is very thin! Guess how I know this is needed!
Great Video. Well explained. Your patient clear approach in explaining your actions, and why, was excellent.
Most utilities run by tiers, thus you have to switch to time of use to save.(Charge during cheaper rates and use batteries during peak hours.).
Great video! Never knew that wire strippers also cut screws. I've always wondered what it was for, but I never looked into it.
that was new for me to
I was thinking “and that it the think I’ll take away from this video”, when I got to that part.
His strippers have threads, too, to hold the screw being cut more securely. Mine doesn’t.
David, I'm a BIG fan of DIY and have built my own dual-tracker solar system to power a great deal of my house. I'm putting a system together now to do the same for my garage and its power tools. I note the batteries you're using in your presentation are priced at $3.25 ea (according to the "Battery Hookup" AD for your DIY project to build a 100AH battery). So - that box of 100 such batteries you purchased cost $325.00 not including tax and shipping - unless you managed a "deal" with the supplier - not in evidence here. I can purchase a commercially produced Sigmas Tek SP 12V 100AH battery at retail for $133.00 (not including tax + shipping). I personally can't see the advantage of building your own battery with costs like that. John
This video was put out in oct 2020, perhaps costs have changed.
John you must not be aware of the difference between the lead acid Sigmas Tek SP battery you spoke of and this battery.
A low quality sealed lead acid non spillage battery costing about 145$ discharged by 80% will have a cycle life of 500-1200 cycles and last a maximum of 6 years at which time they will be completely depleted.
Most lead-acid batteries experience significantly reduced cycle life if they are discharged below 50%. This means you can only receive 50% of the maximum capacity from the battery without doing damage to it.
Every time you discharge a battery of this type beyond 80% you will decrease the cycle life and expected maximum life drastically and severely damage the battery. Cycling this chemistry to 100% discharge you can expect to kill the battery outright in only a few excursions. I did so with 4 fully charged batteries that were 4 years old a total of 5 times after which 3 of the batteries became shorted internally. To safely use this battery type and receive 100AH of usable power from them you would need to purchase and use two 100Ah batteries.
The batteries used in this build are lithium iron phosphate batteries and a 12v 100Ah pack similar in form-factor to a single lead acid battery can be commercially bought for 325-750$ depending on quality.
These batteries will have a cycle life of 1000-10000 cycles and last beyond 10 years at which time they will retain 70% of their initial maximum capacity if cycled to 80% discharge when used. You can discharge these batteries 100% without risk of ending their life immediately which means you can use up to 100% of the rated capacity of the battery without doing life ending damage to it.
It's recommended to not discharge this battery type beyond 80% if you want to reach the rated cycle life.
To put it another way,
you would need 2X the capacity of lead acid batteries (200AH) to reach a maximum 1200 cycles or 6 years of use,
and need only one lithium iron phosphate battery (100AH) to reach a maximum 10000 cycles or 10 years of use.
At this rate you could fully discharge the lead acid batteries once every 2 days or discharge the LiPO battery 3 times a day.
The lithium battery can handle 6x the charge discharge cycles at a greater discharge amount and last nearly 2 times longer.
80 batteries were used in this video at a cost of $2.93 each costing 234$,
not 100 batteries at a cost of $3.25 each. See 41:27 for a cost breakdown.
Prices change over time.
New larger battery packs are available for LiPO chemistry that reduces the number of cells needed to build a 100Ah pack to as few as 4 cells vs 80 shown in this video.
In my experience both battery types mentioned above can fail much quicker than the advertised expected lifespan but by far the lead acid battery can be expected to fail prematurely.
@@btwbrand
What’s the good deal these days?
I’m looking for some lithium.
Might go the route in the video or Chinese cells though ordering from China will take long time
@john Hudson
Pretty much in short, the battery you mentioned should only be discharged by 50% or less which means you can only use 50% capacity.
So multiply your battery by 2 to get comparable capacity to the battery in the video.
Lithium’s also last longer
@@btwbrand Yes >>to all of that
awesome build video, thanks for sharing! I've been wanting to do this type of project for a while and it's nice to see all the steps laid out.
The biggest concern i had was at 12:54 where you folded over the bare metal positive onto the cells. I believe the cell housing is also the negative terminal of the cell. That means the cell insulation is the only thing preventing short circuit and fire. Personally I would put some more paper and tape to make sure there's never an issue there. Maybe you did it off camera or i missed it . I hope your battery doesn't see much vibration and stays intact!
also, for those cutting threads, it's a good idea to first put a nut or 2 on your bolt. This way you can file down a taper after cutting the bolt, and any damage remaining on the threads will be repaired by the nut when you remove it. Usually you don't have too much of an issue, but adding the taper is helpful for starting the threads, especially in hard to reach places.
I posted a follow up video where I answered the top 10 questions. One of those was the positive terminal. I took it apart and added more insulation. Good catch.
@@DavidPozEnergy very good to hear! Also thank you for teaching me/ reminding me to always read the pinned comments!
@@DavidPozEnergy I'm glad you got that before it became a big problem.
Awesome battery, it's a shame Battery hookup want twice the price of cells to post to Australia.
Awesome stuff. Thanks for putting the price breakdown at the end.
All in all, a nice presentation. Thanks.
@39:48 For brand new LiFePo4 batteries, the pack series sure seems unbalanced: 161mV min>max. It would have been interesting to see what their individual cell capacities were, prior to assembly. Never used lithium-iron phosphate cells myself, so am unsure how matched they should be, out of the box.
That way you could have used Repackr to arrange the battery cells, into each string, & balance out each 1S string, to minimise capacity discharge inequity. Which is what DIYer's do, when using repurposed Li-ion cells. Just for reference, I built a portable Li-ion 3S72P battery, from used laptop batteries, & it gets to 105-125mV separation. Never tested it to full DOD yet, as the inverter does not allow it, due to VDC discrepancy.
I do like your videos though, David.
most of us would be in 500 troubles a day if we took the missus iphone for several hours or days for testing
Cost of what you learned on this project? Priceless. ( Great video, thanks for the cost breakdown at the end.)
I learned something new today, how to cut a screw using wire cutters. wow
Yes
Nice one lol
24:30 me too lol
Top 10 Questions Answered here: ruclips.net/video/sPZwL1z_qxI/видео.html
Amazing video!!! Very professional building from this man. Thank you
For what is the insulation paper between anyway connected positive and negative poles? Why no additional insulation rings (fish paper) on the plus poles are used? Why use such a expensive spot welder with overheating problems,when the much cheaper cx4500 does the job without cooling brakes?
Video Title: "Save $500/day when you DIY your own batteries!!!"
Who, exactly, is spending $182,500 per year on batteries?
i checked my electric bill for the past 3 years i paid 18,000 dollars
Clickbait title
I believe it should be read as "save $500 in batteries in one day's work"
@Sky Man while six gauge wire would be better if he was matching his wire size to the size of wire on the BMS. You will also notice that there are two 10-gauge wires each can handle up to 30 amps at ten feet without a 3% voltage drop so they should be able to handle 25 amps at less than a foot just fine
While I will agree the title probably should have read save $500 today when you Diy your own battery as while he did play it safe with this battery and making it only pulling 50 amps if you doubled or tripled up on the nickel strips you could pull more than a hundred amps which would mean that this battery that cost less than $500 would be equivalent to a brand of battery which cost $1,000 and has the same capacity
David, that was a treat to watch. Thank you so much. I really enjoyed it.
Of course they are over capacity cells! Remember, you ordered 65mm tall cells and they used 70mm tall cells. That gives the cells 7% more capacity right off the bat.
Although it makes them useless to most folks spec'ing 65mm cells for specific sizing.
Nope. The extra 5mm comes from the protection circuit soldered to each cell. The cell itself is 65mm, and has the same capacity without the protection circuit.
Great Job & tutorial. TIP: I use small round Molybdenum magnet discs to hold my nickle strip in place until I get it set w/a few welds.