LG Cells Part 2, 6kwh 48v DIY Battery
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- Опубликовано: 7 фев 2025
- Part 2 video. I'm finishing the assembly of the 48v lithium battery. I'm also doing a capacity test and final touch-ups.
I'm sorry about the focus. This is a new camera for me and I need to learn the features of it.
The battery tested great at nearly 6.1kwh!. That means the cells are testing as new. Fantastic.
The LG cells are for sale at Battery Hookup. Use my coupon code for 10% off. code: DAVIDPOZ
Cells: bit.ly/2VcEM4L
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BMS: Daly brand, 14s, 200 amp. s.click.aliexp...
Disclaimer:
My videos are in no way intended to be instructional "how-to" lessons. I am simply documenting my project for informational purposes. Property damage, personal injury, or death may result, even when following manufacturer's instructions. I cannot be held liable for such damage or injury. It is YOUR OBLIGATION to ensure that you are complying with any local and federal laws as well as code and permit requirements.
David you are a true inspiration to me. I watched your first few videos recently and your comments about leaving oil behind because of your time spent in Iraq and now seeing how far you've come is truely jaw dropping. You are living life with a purpose and it shows. I hope to follow in your footsteps with my own journey.
If you start building your own system, and have questions, send me a message in Facebook.
@@DavidPozEnergy I will do that thanks David!
I just picked up 98 of the cells from battery hook up. I drove 6 hours to save on shipping costs and taxes. Saved almost $600 between the two. Those guys are awesome and gave me one h*** of a deal. $93 per kwh. Thanks for the videos dave.
Glad to hear it.
Thinking of using two 6awg wires to connect each of the cells to each other. Should be good to 200amps. Especially being only 4 inches or so. Or I'm gonna go the route you did with your suggestion of aluminum square stock from my local hardware store. What do you think?
Yes, you can use little jumper wires between the cells. I'd be cautious about putting stress on the tabs, so if you can, use an ultra flexible wire.
I agree. I also thought about using zip ties to keep the wire bent and the stress off the tabs. Or even go straight down from one to the other with virtually no stress on the tabs.
Thanks Dave! I just ordered 28 of these cells today using your discount code. Just wanted to pass along something nice BatteryHookUp did. Ryan called me after I placed my order and informed me they have an extra discount for “bulk” orders. He refunded an additional $140 for me! Very honest and reputable company since I wasn’t aware of that and never would have known. I highly recommend them! Looking forward to building my battery. I appreciate the time and extra efforts you went thru to produce and share this video. Best wishes!
That's awesome he did that for you. I agree, they are great people.
@@DavidPozEnergy I also ordered 28. I ended up returning 10. I was going to return more for very short leads but in the end I kept those. The ones I returned had either puncture marks or dented corners. In one case the electrolyte was leaking because the dent was so severe. But Battery Hookup sent me a UPS label and I shipped them back, no hassle. I asked them to inspect better and not send me this type of quality again. But I hope they don't end up going to someone else. Another observation - I ordered same BMS as you. But they changed the product a lot. Now the balance lead connector is on the side and the P- and B- are also on the side. In addition there are two each of P- and B- which must be connected in parallel. I think this is good as it distributes the current from two points and two wires instead of one. But one of P's and one of the B's covers a mounting hole on each side. And I mean, you can't even use it normally anymore. I had to tap the hole with a 6-32 and come in from below, which was a hassle. Last part of the saga...one of the two BMS's was DOA. The offer from Daly is I ship it back to China at my expense, they repair it under warranty and ship it back to me with my next order (which I don't have a next order at the moment). So that's a bummer. But I got one 6kWh hour unit up and running. It's perfect! Thanks David.
@Bucky Cage That’s unacceptable from Daly. Who did you order it through? If you ordered it from someone like Aliexpress you can definitely get a refund
I bought close to a 100 of these cells and I believe I may have found something easier than using the square aluminum tubing. Some of the tabs are Extremely short. Some I've came across are only about a quarter of an inch maybe 3/8 of an inch long. But I found that if you get aluminum C channel you can't tuck it in much closer to the tabs. This has worked great. I have two of my 7 14s 48v banks complete. I believe the c channel is 3/4" x 1/2" x 1/16". Bought it at home depot for $13 for 8 ft.
Show us!!
Yeah this would be essential viewing
I did mine like David did and I already had 10 feet of 3/4 square aluminum tubing at home but only a little 3/4 flat. I saw the c channel there and kinda thought about that BTW I used 35 mm m6 1.0 stainless bolts and nylon type lock washers no separate washer (I know but they dont get hot enough to matter) and I used a 1/8 flat 3/4 bar marked 2 inches increments with holes drilled 1/2 inch in from ends or 1 inch apart for 48 inch piece and used this as a template to drill holes in other bar and tubing . I found that either one 1/8 "washer and one 1/16 thick one or two 1/16 inch thick ones gave me a little more space to work on the terminals. A drill press really comes in handy for this. I did notice that 1 inch square tubing was more available and cheaper than the 3/4 inch size at home depot and lowes. I think the 3/4 is probably easier to work with but with the 1/16 washer pieces it might pull the tabs in a little less (actually 3/4 x 1 inch tubing or bar is probably ideal but not available). You dont have to cut them exactly 2 inches as long as holes match up. Speaking of holes, I drilled my holes 11/64 inch and I couldn't see buying the pneumatic punch so I used a regular old notebook paper type punch. The holes were slightly small essentially threading the screws through them until I started chipping of one edge a little after making the initial hole. This punch takes a lot of hand strength and really only can do one tab at a time but if had longer handle would be much easier . I looked into getting a leather punch with multiple sizes or light duty metal hand punch that was similar but none were in stock and I wasn't sure about how easy it would be to get it in correct position with the wheel at the end. I can also say it is somewhat harder to punch the positive end . Also remember the tabs will be slanted down a bit .
I am currently using one of my packs on Club Car DS 48 volt golf cart and think I may be able to use the golf cart charger if I add one or two more cells to avoid the equalization phase and program BMS to shut off before the equalization mode. I am going to post in comments on his golf cart conversion video.
The cells started oozing a gel out of the ends where the tabs come out. They have not even been hooked up to anything. I was waiting on 8 daly smart bms. That took almost 2 months. When installing the balance leads i noticed the oozing. Ive been trying to reach battery hook up about this with no luck.
Based on your recommendation, and videos, I am about to pull the trigger on 228 of these modules.
I appreciate your efforts.
Wow, that is going to be one big battery.
Do you have pics? What kind of Charger/Balancer/Inverter do you use?
In theory. The pack with less resistance is going to get the biggest percentage of the load. If you you want to control the amps for each battery pack. You need to install an amp limiter for pack. But You shouldn’t worry about it, that’s why you installed BMS’s. Thanks for the discount code David, I just ordered my battery pack.
Just ordered 56 of this cell's for my off grid powerwall . I used your discount code DAVIDPOZ and got 10% off....thank you David!
I'm glad you were able to take advantage of the 10% off. Thanks for watching my videos.
Hi David! What is the setup for Bulk charge & Floating charge for this battery pack?
Mixed battery chemistry... interesting, look forward to seeing how they share the load. I would guess the little 6kw pack is going to be hit harder at the ends since the LiFePo4 has such a flat discharge curve in the middle.
I have been doing that for 4+ years. It works of you know how it works
@@DIYTechRepairs Is the LiFePo4 charging the NMC on the flat curve?
I forget the flat curve property of lifepo4
That is the exact battery I need right now!!! Done....
They are brand-new...
Looks fantastic. Great job on getting the tabs connected using the AL blocks.
With what you know and understand, I think those batteries will work just fine together.
Great videos David, finally a real human on RUclips :-).
Looking good! That's a nice, well performing and lightweight battery!
Another great build Dave. If I got my figures correct I am thinking around $850-$900 plus a whole lot of time per battery. But, the reward is a powerhouse for the money when compared to other batteries capacities and weights. I also like the extra touches you add to make a professional eye pleasing look that speaks out to the general way you do things. Too bad they won't charge below freezing temperatures or I might be rethinking my LTO battery bank system. Their price is extremely attractive to value. Thanks again for another great video and I am still awaiting the completion of your water storage tank system.
Cover one side of the cells with a heated mat on a thermostat to maintain the temp above freezing.
David your enthusiasm is contagious!! That is why I love to watch your videos. And your the main youtuber that I follow considering I am doing almost the same thing your doing for a solar setup. To bad I live so far from you. I would love to help you when you need help. Keep up the great work. How do you like the BMS so far? How will you be able to reduce current while charging it? Thanks again for taking the extra time and work to produce your videos for all of us.
Thanks for watching. The BMS works fine for my purposes. I tested it in an over-voltage situation and it immediately shut off preventing the battery from over-charging. My solar array puts out a peak of 80 amps. Those 80 amps will be distributed to the whole battery bank. I think it will split between this new battery and my tower. I'll be checking to make sure, but I don't think I'll have to do anything special. The cells can take a 100 amp charge, but they will get warm. Remember, these are used in electric cars, and they can go to fast charging stations.
@@DavidPozEnergy True but also remember they have liquid cooling in the cars. It should work well at 100 amps though as you already mentioned they only get a little warm to touch at that rate.
wow that is putting out as much power if not more than my 12 lead acid battries at 80 AH each. wow. NIce Nice.
This is awesome. I am in Thailand and wanted to get these things shipped over to replace my dying deep-cycles but wasn't sure how to put them together. Thanks dude. F#%$ing A!
yeah, had 4 cheap lead acid. now after 2.something years they dead
glad you put the notice up about the focus in the beginning - I'm watching on a freshly set up pc, running mac os, so double trouble. These cells look really nice, stack together well, and quite compact. Shame they butchered them with the dremel. But your cluey ingenuity crafting those washers and blocks in the last video solved that issue! :)
yeah, sorry about the focus. I bough a DSLR and haven't figured out all the settings yet.
It will be very interesting to see how the different chemistries behave. They should charge based on the internal resistance at a given voltage at that moment . The flat voltage ranges of the Lifepo will likely result in the LG cells reaching around 3.2 volts first then the lifepo will suck up a lot of watts/current until voltage starts rising again. Of course since you will also have much different Kwhr capacities that will also make a big difference.
David, you might want to look into panel hanging brackets (they go by many names). Essentially they are half of a dove tail. You mount one "strip" on the wall(open end facing up) and then another on what you are hanging(open end facing down). They typically support a couple of hundred pounds and if more support is need, you just mount two sets one high and the other low. When you go to hang your item you just drop(slowly) one edge over the other. Typically you use a couple of mounting tabs screwed into the wall on the bottom to keep it from sliding off the wall bracket left to right.
Thanks for the tip.
aka 'French Cleat', used a lot in woodworking and cabinetry and would be ideal for hanging something like that battery pack on the wall
Purchased 3 6kwh Bolt batteries with your referral code! Thank you! Going to split one of them into 3 parts so I can get two 48V 8kwh+ batteries out of it.
Fantastic! Sounds like you will be at 15s. Great.
@@DavidPozEnergy I'm going to be 14S taking two out from one pack so I'm only adding 4 to each 10. I have a Chevy Bolt(I can see my cell voltage) I tested the max Voltage range and found. It would only net about 60% capacity with a LV5048.
have you done a follow-up to this? I'd like to see how they've held out in 3 years. How much capacity they are still holding.
It seems like when you are setting up your battery packs you always seem to target the low end of the voltage window. Here with 14 in series you have a 42-52V window. If you went with 16 in series you would have a 48-59 window. Same size window (10V ish) just moved higher. Most inverters and charge controllers go to at least the lower 60s in voltage. The higher the voltage(within reason) of the battery pack the more efficient the inverter runs (shorter voltage step). It also slightly increases your Kwhr rating(V*A). While in some areas code limits the voltage of the pack to 48V, most allow the operating window to go up to 65V( allows you to boil balance lead acid batteries).
kWh rating goes up, but not for free. You have to add 2 cells per string.
That's a pretty damn nice battery. Nice work! Let us know how paralleling them with the LiFePO4 works out. I've been thinking of doing something similar.
Thanks for your comment. Yes, I'll let everyone know.
I have been running that in parallel for 4+ years. It works but you need to know the difference
Awesome pac. 6KW light weight small footprint.
I bought 28 from Tom per your code. Sweet. I think I will take the 7 pack apart and do the 14 S with the simple flat stock clamp. Thanks
Cool. Should be simpler. I'd love to see some photos of your build. I'm on Facebook facebook.com/DavidPozEnergy/
any update on your project?
I think I heard somewhere that the Bolt specs show 200a max discharge and 48a max charge current. That is with 3 cells in parallel. I think the 48a spec is also just from the max available onboard charger.
It's alot easier than assembling 1,000's of 18650's
100% agree. Unless you are doing that for fun or a true believer in saving the planet by recycling these, the time spent / value proposition is extremely low.
As you know, 12V is an RV/Van Life thing (...& of course also Preppers), That said, 12V appliances and equipment are incredibly efficient (although expensive because of poor economies of scale). That could change in the future, with people in the know focusing more on that Voltage. I'm trying to figure out (currently) how to charge my 12V banks with my 24/48V battery banks (Stepping down and regulating the voltage and current), As those higher voltage battery banks charge much more efficiently large solar panels (especially 72 cell+ panels, which coincidentally are the cheapest on the used market due to their size and weight).
Great and neat work David.
That really looks good. You should slap a big sticker on it like a big POZ with a lightning bolt!
You're awesome. Keep it up!
For those playing along at home, that's ~185W-h/kg. In the pantheon of lithium batteries, that's pretty good. There are much higher density systems on the market, but not for the price of a wrecked Chevy Bolt battery module! I need to do the math for the LiFePO4 assembly going in the Electrica. (each cell has been tested to ~200Ah, I just don't remember how much each of them weigh, or how much is being added in cable and securement -- rough estimate 140-150Wh/kg. The BMW bricks are ~90Wh/kg, on paper [40Ah (C/3) cells].)
I would be thinking those Cells may not need to be compressed against each other so tight. I believe they need to be able to expand when they fail at some point so the pressure does not rupture the package. I could be wrong but you might want to look into that .
Jim, I was thinking the same thing. I am just about to start thee same build and I was thing of spacing them about a 32nd or 1/16th “ to let them vent a little.
heya yes that is a nice small package for 6kwh
David, you've come such a long way since your earliest videos, man you are turning into a lithium god. Wish we could get those cells here in Australia at a reasonable price.
Thanks. They come out of a Chevy Bolt EV, so maybe you can find a crashed one at a junkyard and salvage the battery?
I know this was done 8 months ago, but thought to comment anyway. Easy way to know which pack will take the charge away from another (for a while) would be to know the internal resistance. Energy will take the easiest path. The pack with the lowest IR will take on the majority of the energy. You can actually play mathematics to predict State of Charge of one or the other.
I built a 24v one right now and its just waiting for its bms which should be in from daly in a week
Wow NICE brother 6kwh is kick butt!!
Gaffa tape, not duct tape. Excellent video, exactly what I am looking to construct.
Good job. Nice battery pack, good for DIY electric car.👍
wow that is nice. I mean I have 12 lead acid batteries at 240 amp hour. and you pulled 1300 watts. my battery bank would be dead way before that. I may really have to think about this. I wonder if I get 4 of these and I think as a back up I would run for a good while.
Dude, you even make black duct tape look professional!
LOL, thanks.
DavidPoz I laughed because you were just talking about “showing off,” but yeah, that looks tight. 💜🤓👍
Think you should have airflow space between cell blocks for proper cooling. May get a bit warm in the middle of all that.
2:00 I wouldn't recommend discharging to only 3 V per cell. Based on what I've read about these cells, to prevent damage and degradation, their cutoff voltage should be no lower than 3.2 V.
Capacity test is to 3.0v per cell. But staying higher than that is good for day to day operations. I don't discharge below 3.4v/c on a day to day basis.
@@DavidPozEnergy Yes, I think the ideal operating range would be 3.3 to 3.9 V. That should give you over 80% of the rated capacity.
But looking at the cell specs, anything under 3.2 V will damage the cells. The 60 Ah capacity rating is based on a 4.1 V to 3.2 V discharge cycle.
Dave! Wonderful build. Can you kindly provide a brief update on these LG cells, how numbers and depth of discharges, capacity, etc. trying to decide how many to get upfront. thanks.
They are staying in balance and working perfectly. I really like them. However, right now I'm not cycling them daily. I have them connected to my Sigineer hybrid setup in a test situation.
@@DavidPozEnergy Thanks so much for the update. Usually, if a deal seems to good to be true, you know how it goes. Ordered 14 to make a pair of 24v@120aH for now to be compatible with the inverter/charger already onboard. It is 24v 3,000 watts continuous. Other parts of system are 24v so going to 48v is going to be speedy, especially since all the other 24v equipment needs upgrading as well. Going to do solar panels and charge controller next, then reevaluate a move to 48v. Not sure it makes sense once all the cabling is sized for 24v.
Probably going to add another 7 to the order. :)
thanks again.
Good stuff. Yes, I've bought my share of dud battery deals, but the LG's are (nearly) new, so they are the best ones I've ever worked with.
Yes.👍
Very very nice dave!
I have wire leads with spade connectors on wire leads . So that way I do not wear out the screw heads.
great video! I would keep some space between the cells for cooling and to allow small expansion of the celss to prevent fire (remember samsung Note fires?)
Hey David, I saw GM is recalling the chevy bolt lg chem for battery fire when fully charged!! Maybe a video on the topic?? I am running 7s 8p with these cells.
@DavidPoz - Impressive. Your 6 KWh beat my 8 big AGM 6V 230Ah "golf cart" batteries. I only safely got about 5 KWh out of those and they weighed about 600 pounds total. I sold them months ago. It is a shame however, either how much someone has to spend on lithium batteries, or how heavy lead acid batteries need be to even get an electric heater to run overnight. I kinda gave up on solar because the expense is still way too high. I get assistance for my electric so many months out of the year, my electric bill is $0. I sold a bunch of my solar panels and only have a few remaining.
By the way, I wouldn't really call that a 48V battery cuz lead acid batteries never go up to 58V full charged, more like 52V, but I see what you did... you took the anticipated inverter cutoff voltage of about 42V and calculated how many 3V (drained) batteries you need in series to get that. So that worked out to 14 in series. I supposed that is ok if the inverter being used accepts 58V. I suspect a few out there might "complain". I have an old APC brand 48V UPS but I don't think I ever tried to "feed" it that much voltage. I remember when I used to and had it externally charged (under load running an HDTV), I had the solar charger controller (scc) set at something like 55V max since it was charging four 12V AGMs in series. Since I only had one solar panel (not even optimally angled) and the HDTV was high wattage (100W or so), I barely got any charge into the battery bank. It was staying about "even". Just a temp setup to test the equipment. It worked though. Can't expect anything to charge when the scc was showing a little over 100W on average and the HDTV was sucking it all up. Plus there are losses in the wiring and other losses too. Of course you already knew that but some other viewers might benefit. I think after losses and non optimal sun, whatever max wattage the panel is rated it, you will be lucky if you get the equivalent of half of that for 5 hours a day. For example, a 200W solar panel will likely not give you 1 KWh per day on average, but I bet it will give you something much closer to half of that. That would actually be a good experiment, but not so easy to do.
In my direct experience with using an APC ups inverter with a 14s lithium bank, the upper voltage is not a problem. I reasoned that it will charge its lead acid original battery to just over 14.4v which is their saturation level. I've found the inverter fine with my battery getting to 57.6, which is a fair compromise between capacity and life span. I switched to lithium and love them. Bought new, absolutely equal cell to cell, I've found no need for a bms, as charge/discharge rate very low. I check cell balance at least once a week 😁👌👍
Ps, in summer, I've got rated power from my panels and exceeded it on cold spring days. I live in the south of England.
6:10 Just because the ferule deforms doesn't mean it's a great connection. Correct crimping will actually cause all the wire strands to cold weld together creating 1 large wire. The ferule helps to keep them all together to make that welding occur. If you were to use a thermal camera, you would probably find that the non-crimped ferule will get hotter than the crimped one under full load. Heat = loss of energy. The more heat that is generated, the weaker the wire will get. The weaker it gets, the more resistance the wire has. The more resistance, the more heat, etc, etc, etc.
I would recommend to keep crimping them just be on the safe side above all. Crimping also means there are never ever any stray strands.
People get too excited over “cold welds” which almost never actually happen with homemade connections.
My gut says you should have some allowance for the swelling of the cells when fully charged.
I agree, I see no benefit in compressing the stack, it may actually lead to failure.
This is how they come from the factory.
@@DavidPozEnergy Perhaps seeing a failed battery could tell you if that extra cutting board is a good idea. Not long ago, a cell phone manufacturer created a serious safety issue, because part of their manufacturing process compressed the battery pack and it lead to some catastrophic failures later. That said, those were Li-ion batteries, so if you're not dealing with the same chemistry, swelling and dendrite formation may be quite different. Check to see what Failure Modes and Effects analysis is available for your chemistry.
@@DavidPozEnergy I was thinking about the cutting board on the bottom compressing the bottom cell. You are right - the others have the plastic spacers.
10:01 *Lifts a heavy thing on a ladder* “I’ve got some big nuts here” - Hahaha
That's what im saying now see how cool it is 🤓 and it looks perfect battery 😊 and why didn't you wrap the whole battery.
Thanks. Well defined.
Nice work, please keep it up.
These cells certainly deliver an inexpensive, compact battery, pity I live in the UK :). I wondered what the voltage spread was like at the end of the discharge test - don't think you showed it ? As an average you stopped at 42v so 3v/cell average.
I'm sorry I didn't show that. I did check each cell and they stayed equal through the whole cycle. These are really good cells.
Recently there are not so good news about LG cells for EV-s. Are yours also the same that have been recalled? Otherwise maybe you should locate them away from the garage?
With the heat generation you spoke of, shouldn’t you have a space between the pack an the wall? Or at least some fire seal material? Love them build!
I installed it with a 3/4" air gap to the wall.
@davidpoz if you were starting from scratch, would you go with your old 6kw aims inverter and charger or start with the 5kw all in one inverter your friend installed?
The Aims inverter has a much better surge capacity than the MPP Solar inverters. So I would stick with low frequency. But I needed more capacity than the 6kw, so maybe a 10kw Aims if I was starting from scratch.
@@DavidPozEnergy thanks for the reply! Love your videos man. Keep kicking butt and stay safe
Does that BMS trigger the breaker in case of an imbalance or is the breaker stand alone? Do you trust that BMS? Is that a Daly? Balancing amps?
This BMS does not trigger the circuit breaker. This BMS is a Daly brand with 30ma balancing. I always find the question of trust to be an odd choice of words. I feel comfortable. The BMS has reduced my risk to an acceptable level for my risk tolerance.
Hello, I just found batteryhookup selling these lithium batteries on my hunt for energy storage
So I would need 28 of these bad boys to make 48v 10kwh-12kwh battery bank for my setup? :)
Yes, it would be 12kwh, but you might only want to use 10kwh to extend the life.
@@DavidPozEnergy Deciced to go for the Lifepo4 batteries instead to gain the longer cycle, what are the typical used sizes & price a piece, the cheapest I've found is about 2.3-2.4$ using Ali.
Further in my search, I found these German made batteries which had a great cycle life, called Bae Secura, which were quite expensive while still using the old fashioned battery technology.. :D
So, what was total cost😊
thanks for the vid
I would like to see a capacity test for this pack after 2 years...what's is degradation %....
That would be fun. Thanks for the suggestion.
Nice build Dave. Could you go a bit more in details about doing a 24V system ? I realize it would be 7 modules each having 2 cells for a 7s2p battery in the end. What I dont understand in your video is when you say wouldn't need an aluminum block. Since the tabs were too short in your application why would they be different for a 24V ? If you could please clarify this for us.
I was suggesting building a 48v pack using 14 cells. When you buy these from Battery Hookup there are two cells per module. So I said in the video you can buy 7 modules. Not 7 cells. You can then arrange them 1p14s. Now there are only two tabs to connect instead of 4. The two tabs would be so close that there would be no need for an aluminum block between them. This would make the whole build simpler.
@@DavidPozEnergy ok, so if taking the 2P modules apart, you dont need the blocks and you only need blocks when you keep the original 2P configuration?
Right. It has to do with how close the tabs are.
@@DavidPozEnergy In your part 1video, it seems as though the spacer between the cells is bonded to the two cells, since you didn't separate them and you were curious about what was that spacer material. I want to try the 14S with individual cells, as you suggest. But I wanted to know if it's really possible to separate those two cells and flip one around. My second question is on pressure. I know it is beneficial but it seems ambiguous on the best way to do it. Your configuration in particular will have 71 lbs on the bottom cell plus whatever force is coming from the threaded rods, so the top and bottom cells are seeing a big difference in pressure. My idea was to use unthreaded rod, greased, and mount horizontal using some strong springs on each rod. That will equalize the pressure and it will be roughly constant, whether charged or discharged (volume varies based on SOC). What are your thoughts?
Hi Bucky Cage, I have not separated the cells. But, I did discuss this with Battery Hookup. They separate the cells when they take the assembly apart. This is because the big assembly is 3p10s. So every other pair of cells is opposite. Battery Hookup flips them all to be parallel for shipping. They said they use a flat plastic putty knife.
I like your idea of using springs. That sounds great.
well that sucks they don't sell them anymore I would love to get enough to build 4 of these.
Yeah, they are sold out of these at the moment. Right now Battery Hookup has some very nice BMW cells that may work. I have some in 5s and 4s, to make 14s. batteryhookup.com/products/bmw-oem-5s-19-2v-75ah-1-44kwh-battery-module
I linked to the 5s, but they also have 4s and 3s, just go to the homepage. You can use my code DAVIDPOZ for 10% off.
David , I just bought 70 cells (they were out of 36 volt packs) using your code. Just wondering , have you tried what you mentioned at end of part 2 swapping the individual cells in case to connect directly with screws rather than using the blocks ? If so how did it work? Interested to see rest of your golf cart build and enclosure you make for battery itself, heat sink etc if needed. later get a used newer 48 or 72 volt cart and put aftermarket motor in like 10 HP larger diameter tires with lift kit and with parallel battery you can have a street legal 60 -80 mile 26 or so MPH vehicle and with off road tires like a 2 wheel side by side !
I have not personally swapped the two cells around. However, since this video I've been e-mailed photos from several people projects telling me it was very easy. No glue. The black (foam-like) pad between the cells is sticky, but not glued. no damage to pull the cells apart and swap them around.
As for the Golf Cart, I need to learn more about the different options out there. I would like to do some fun modifications.
the only thing I would change is instead of a solid block I would use square tubing it would hold the current be cheaper to buy and be so much easier to drill :)
That's exactly what I said in part 1 video.
@@DavidPozEnergy haha thats funny, I don't remember that.
@@DavidPozEnergy Which diameter should be this aluminium square tubing. Please can you refer us an example?
i would give some gap between cells and add cooling fans
Hi Dave - Will you have a follow-up video anytime soon to share your testing results for this pack now that you've had it online for a month or so? Thanks!
It is working well, all the cells are staying in balance. I don't have plans for a follow up video right now, just too many other things to get to.
I've been pretty hesitant to buy these packs but it for damn sure beats spot welding 135 21700's lol.
I've cycled it a few times now since the video and I'm seeing great results. Makes me want to sell off my LiFePO4 packs, LOL
Hey David i just bought 2 of the 36 volt packs from battery hookup I'm making a 7s 8p!! I have 2 Victron smart 100/50. How did you set up your absorption and float voltages per cell?? Any help will be greatly appreciate. Thanks Man for all you do Keep it up!!
That sounds great. I usually stay below the max voltage of 4.2v per cell. I do this to extend the life expectancy. Usually I set bulk charge (absorption) to 4.06v and float to 4.04v or something like that. The trick is to keep your charge controller from jumping back and forth between the modes, so set them far enough apart to prevent that.
@@DavidPozEnergy Awesome!! Thank you!! My bms does not balance till 4.18 per cell. What do think about using the manual equalization ( so i can monitor it ) at 4.19 maybe once a month.
That's fine. These are new cells so they won't need much in the way of balancing.
Nice battery ! Is this coming from an EV ? Impressive size for capacity !
Yes, out of a Chevy Bolt.
If you had 14 and wanted to make a 24V battery how would the BMS connections be? I was comparing these to the Leaf battery, these are far more dense then they are. what did they charge to ship it to you or what did they have to pay to have them shipped?
@10:00 yes, yes you do. That's a bunch of stored energy you are horsing around. I'd hate to see what would happen if that pack fell and hit something the wrong way.
you caught that too
Has matsh fol charger for 1 batry?? Bles
Thanks great videos series
David Poz, What is the charging amps you decided ended up being a safe amperage? Also when you tested the capacity what did you deiced was full charge Voltage and full discharge voltage. I purchased 3 6kwh Bolt EV packs from Battery hookups with your code, thank you for the help and hopefully my purchase helps you out.
Hi Darren, I tested charging at different amps. At 60 amps my pack was warm, but not hot. Since this is a 120 amp*hour pack, a 60 amp charging is a 0.5C rate. I think that should be the limit unless you include some kind of active cooling.
I personally charge these to 4.05 volts per cell, and discharge to 3.40 volts per cell. Since my arrangement is 14s (14 cells in series) my pack range is 47.6v - 56.7v
@@DavidPozEnergy Awesome that is very helpful. I bought 3 of the full packs and split one in 3 parts to create two 14S packs. I'm currently chargeting the two packs at 30 amps and running them from 45V to 57Volts, but 47.6 is still about 30-40 based upon my Bolt battery pack, I have a Bolt EV.
Great! Just wondering, what's the maximum number of packs that can be paralleled together for a HUGE battery bank?
The joking answer is: "The maximum your budget can afford". LOL. But seriously, you can parallel as many as you want. You could parallel 100 cells together before series connecting them if you have the money and space for it. If you decide to do an epic build like this, I'd love to see it. I'm on Facebook or e-mail.
SOLD!! Thanks for your videos. Waiting for my purchase to arrive. Will be building two 6s 24v to add to my Tesla Model S trio. How's the BMS working??
The BMS is working fine. I tested the over-voltage cut-off and it works.
Awesome!
Nice
Love the build and I would totally jump on the cell chemistry but I’m just scared of its safety.
Man underrated comment.. There's a reason why you should use lifepo4 for a wall mounted storage battery.
nice energy density in that little pack
Assuming charge/discharge every day, how many years would the pack you built last? What would make it last as many years as you think it will last. I'm asking, because I really like these batteries and thinking about a purchase in the 33kWh range. We don't own a home for now, but when we did, we used around 900kWh to 1000 each month so thinking 33wWh should power the house. Thank you.
There are several factors that affect a battery life span (as measured by cycles). These are EV cells, same chemistry as in Chevy Volt and Nissan Leaf. We can look to these two cars for examples on life span. The Nissan Leaf had no active liquid temperature control, and were used to a high DOD (depth of discharge). The Chevy Volt had active liquid heating and cooling of all the cells directly. The Chevy Volt used only about 75% DOD. There are 2011 Chevy Volts still driving on the original battery with over 300,000 miles.
My point is that the more we control, the longer our batteries will last. With NMC cells, I suggest charging to 4.05v/c (volts per cell) and discharging to 3.50v/c. This is what I plan to do. Next, the pack is inside my garage, which is both heated and cooled. So the cells will never experience temperature extremes. Third, limit your charging and discharging amps so as not to build up heat internally.
Given the controls, I suspect 3,000 cycles fairly easily. Or 8.2 years if you are daily cycling.
@@DavidPozEnergy WOW! That's awesome. Thanks for such a detailed answer. Maybe I'll put mine underground where the temperature, if set up right, will be constant all year.
@@DavidPozEnergy can't sleep and just got done scrolling/reading through all 280+ comments and reading quite a few of your replies. The amount of detail and thought you put into replies astounds me. Well done.
Hi David
I am making up 2- 14 pack 48 volt units that will give me approximately 12 kilo watts, but I want to split each pack into 24volts instead of 48volts
I will then reconnect two of the 24volt units back together to make 48 volts.
#1 - Can you suggest the wire size I should use to reconnect the 24volt units back together.
#2 - should I use 1 bms unit @ 48volts, or 2 bms units @ 24volts.
Which way is best safety wise and cost wise with all the hi temp and lo temp etc. And what is your choice of bms should I use, and what is the manufacturer, model number etc.
Thank you very much. I have designed a way to connect these batteries together that you would really appreciate, I will share it with you if you would like.
Thanks, Steve
Hi Steve, I don't think I'll be able to do an adequate job answering all your questions on this platform. When people are building large banks like you are planning, they often go with a brand like Batrium for the BMS. www.batrium.com/ I'll welcome you to join the Facebook group "DIY Battery". I'm on there with many other people building with these cells.
Great video. I'm designing a very large 48v build based on your video. Would you consider using any other BMS (like the one with bluetooth)? It's fun see voltages of the cells and having control of the balancing function. Thanks again for all the information you're contributing to the DIY community.
Hi Eric, Sure, I'll use different types of BMS. I've used BMS's with bluetooth dongles and they work good too.
@@DavidPozEnergy I looked at the 36v 5.94kW packs (10s3p). The busbar connection in between the cells groups looked similar to yours, just not as heavy duty as yours. I'm ordering those packs to see if I can splice them to make 48v (14s3p). It's definitely more work but more fun as well (if I succeed). You have successfully inspired me to start a big project.
Anything that call itself "smart" is probably a dumb idea for reasons that you you will probably not consider.
Hi, I'm interested in buying the 6kw batteries. Where can I find them?
Did you install the main positive at the top or bottom of the pack and then the main negative at the opposite end of the pack? As to have one at opposite ends of the pack So current will flow more evenly for charging and discharging.
Yes. Main positive on bottom and main negative on top.
Thanks for the reply.
Looks so good and professional i like i want one too 😁 how much you spend on this battery project?
It would cost $835, or about $140/kwh total. Full disclosure though, Battery Hookup sent me these cells at no cost.
@@DavidPozEnergy I am paralleling two sets of 4 BYD modules for a 48 volt 880 amp battery. I am curious as to why copper rivets to attach paralleling wire to aluminum busbars. I substituted aluminum rivets of the same size as your copper rivets but the remaining rivet on the back side protrudes into the spongy material surrounding the positive terminal of each cell. I could not detect it this were so using the copper rivets from your youtube. I purchased the copper rivets from you youtube list and also some more aluminum rivets 1/2 the length of the copper rivets in your description. I have only paralleled 8 cells and I am waiting on the remaining 56 of the 64 cells in my 48 volt 880 amp battery module for your response.
Thanks, Roger
4hrs into the test 47v and 5.6kwH - what does that mean. Does it mean after 4hrs your battery has used 5.6kw or does it mean your battery uses 5.6Kw every hour?
kwh is the total amount of energy consumed. This pack has a little over 6 kwh storage capacity.
At the 6:50 mark those connections from one back to the next is a little to close for comfort LOL.
Nice vid again! (Well, besides the focus issues ;) ) I don't think the weight is of any importance since its for stationary use. When will you continue with your water project?
I don't have a timeline for my projects. I jump back and forth between them based on time, weather, and parts.
Quick question, I have some Nissan Leaf batteries, seven stacks of 24 that’s is a 14s setup. I wish I could afford a batrium leaf mon but I can’t at the moment, would you recommend a 300a Daly bms? I jus need something for balancing. Thanks in advance for your answer
David, I just built a 24V battery with the same LG Chem cells; Thanks for your knowledge & expertise! I am about to build another which I'm going to run in Series-Parallel with my MPP Solar 48V/3000W Ivnerter/Charger/MPPT, Any suggestions? (I will post a video on that build as well).
Have you thought about using these in 12V Systems? The top of charge would be 16.8V (w/Four 3.6V cells), the range would be 12-16.8, primarily discharging around 15V, so i'm worried they will be beyond the acceptable range of 12V equipment and appliances (I hear that range is normally approx. 11-16V)... Let us know if you have thoughts?
Yes, you got that right. Using this type of lithium in a 12v setup will wind up making the voltage a bit too high. Whenever I'm asked about build a 12v system I suggest moving to LiFePO4 chemistry and doing a 4s. That way the voltage is a little less. These can be broken down into a 12v pack nicely: batteryhookup.com/collections/lifepo4-batteries/products/a123-36v-module-w-48-26650-anr26650m1-b and you can still use my coupon code "DAVIDPOZ" for 10% off.
@@DavidPozEnergy So those 39.6V, 9.2AH, 364WH. So three packs could be re-arranged to create a DIY 90 Amp Hour 12V battery for $150, That is awesome energy density per dollar, but it is a fair amount of work (… I've never seen these packs in person so size and weigh could be a factor?) Anyways, 6 of these packs ($300 delivered with your discount!, + BMS), will get you 180 Amp Hours at 12 Volts, that’s a very “RV Usable” battery pack. That’s a really good deal but it's also a fair amount of DIY'ing! Have you thought about what config to use and the easiest ways to build the buss bars, integrate the existing racking? Also, do you have an opinion about the number of charge cycles you should be able to get out of these? I hear the LG Chem cells may rival LIFEPO4 chemistry, although I am skeptical... Maybe I’ll do a video about a DIY build on these, If your already doing one, I could do a different voltage or config, LMK? Garrett
I've got some of these small lifepo4 packs waiting for me to do a 12v build, but I don't get a ton of interest in 12v. Just one of those things I've got to get to.
@@DavidPozEnergy Clearly, I'M super excited about the potential of being completely off grid, which cheap used solar panels and quickly accelerating battery tech is making more realistic every new day....
@@DavidPozEnergy As you know, 12V is an RV/Van Life thing (...& of course also Preppers), That said, 12V appliances and equipment are incredibly efficient (although expensive because of poor economies of scale). That could change in the future, with people in the know focusing more on that Voltage. I'm trying to figure out (currently) how to charge my 12V banks with my 24/48V battery banks (Stepping down and regulating the voltage and current), As those higher voltage battery banks charge much more efficiently large solar panels (especially 72 cell+ panels, which coincidentally are the cheapest on the used market due to their size and weight).
Pls share how I can these battery
Is that a copper to ali joint at 6:06 🙈
Hi David my question is I noticed that you are mounting your 48volt packs on a non combustible surface in most cases. Is there any fire hazard with these new LG cells. I have purchased 28 cells Thank you
There is always risk in everything we do, no matter what. I can say that I'm comfortable using these LG cells with a BMS on board (the red thing), properly sized wires, fuses, circuit breakers, etc. Here is a video from another RUclipsr where he tested a similar cell There was no fire, but it did expel gas: ruclips.net/video/vQjXCL0rId0/видео.html