Me and some friends are building an electric go kart using 18650s, this is going to be very useful! Thanks for all the great work and videos you're doing on the topic.
Damn ! I was thinking it was going to be pain in the Rump to Calculating what batteries would give me equal Cell Capacity. That Program took away the Pain. Thank You !
that program does a similar task to the programs used by the airlines to calculate weight and balance for aircraft, to know how to load the baggage, and balance the aircraft, while making sure that the weight estimate is accurate. interesting. your channel is valuable as always! thanks, Jehu!
I have built several packs and never use a BMS. They always fail and are a pain in the butt! I charge my packs every time with a nice hobby balance charger. The 52v packs I build are split into two 7S packs. I then charge each 7S with my dual 8S balance hobby charger. I believe investing in a good hobby charger will out way all the bad BMS issues I will have to deal with in the future. Plus the hobby charger allows me to monitor cell voltage and resistance which helps determine the over all health of the battery.
Nice reference to the rePackr utility. That helps a lot. I enjoy your battery videos on RUclips most. The LIVE streams can be fun, but not normally as informative for me.
The builder tool is easy to use, spot welding was harder than expected, I built a 7s 15p pack (I wanted to charge 1 amp per cell) ended with a 932wh pack, still have to test to build another one. This video helped.
That tool should add a way to enter both capacity and resistance so you can build a pack that not only stays balanced during slow discharge, but also won’t let one brick sag excessively during high discharge. Sort of like one of your old videos shows how to do by manually grouping the cells and getting the high drain and low drain cells equally distributed while getting the total capacity of each brick as close as possible.
I legit just made this pack lol watching this video on super slowmo didn’t know how to connect the balance leads so this was a great video on that ….your the goat 🐐 🙌🏽🙌🏽🙌🏽🙌🏽🙌🏽🔋🔋🔋🔋🔋🔋👑👑👑👑👑👑👑
Can you put link for one of your videos, a slowed down dummy step by step version that shows me how to build a 36x 18650 batteries 12v pack. Or something similar. Or if you have a step by step video on how you built your Puerto Rico Emergency power case. I would appreciate it. Love your videos man! Keep up staying up.
You SHOULD charge the cells first and leave them alone for a number of weeks and see which ones self discharge to weed out the bad ones. Capacity checking isn't enough otherwise you end up with a pack that keeps discharging itself.
Phizicks the cells that self discharge would not be holding 80% capacity. Especially since the cell analyzers calculate discharge capacity. I guess if these cells were originally 2600mah and reading 1400mah then there could be a self discharge cell but if these are 1600mah cells new and reading 1400mah now there's no self discharge. That means the anode is shorted with the cathode.
Tom Amerman i have seen many cells holding close to new capacity and still self discharging. Roughly up to 0.5% off all my tested cells have had that phenomen. Of course depends on source of the cells.
What about Restances??I have also seen the same but was able to catch this with Resistance testing. I like to resistance tested every cell, looking for the higher ones. those I typically find will self-discharge pretty fast compared to the other cells. Some people instead of resistance testing will just charge a cell and if it falls below 4V, they consider it bad. I have seen cell at almost full capacity, self-discharge with high resistances. Also if you have a cell with high resistance, and you try a measure the capacity by charging, instead of discharging, and you use something like 0.5amps. You will get a much higher Capacity than the other cells. Typically easy to find, based on them measuring 2800mah and the cell is actually 2600mah. The cell is discharging at the end of the charge faster than the charger cycles.(but I am a newbie, and these are just my experience with salvaged cells.) Still a great Video, but my only worry is using Brass strips, instead of copper? I thought this was a no-no? I had always thought he used copper?? I can find brass strips all day long at my local hardware store, just not copper. I have to make those myself.
Back to the basics, I have to do a 7S-12P , I have a 7S windows-android BMS to test on it and I am going to try a Buck-booster to give me 12-14.5V for my 5th wheel LED Lighting Circuit :)
Yeah curious. Or just buy fuse wire. It really is an aspect that "smells" a little about this channel. It would be nice to have a video on how to precisely calculate the needed wire length and gauge for a certain battery pack instead of guesswork. I mean it can be done.
What do you mean by calculate? It's a matter of a few simple physics laws about wire length, resistance and dissipated power -> heat? Or the simple version, look what companies use and use that as well. A little to big never hurts.
www.powerstream.com/Wire_Size.htm I guess you could use the chassis wiring current load limit, which would make 23 or 24 AWG seem appropriate for use as fuse wire in a bus bar. This is assuming soft annealed, nickel-free, solid core wire.
Another Great Video! I like to add a balance cables along with the BMS, just incase I have to balance charge later. You have to be careful when using a BMS and Balancing if you have a charger that does more than .5amps per cell. If your charger does more than .5 amps, sometimes it will trip the protection circuit and cause the BMS to fail, unless you reset it with no charge. Some will allow you to just add a charge and it reset. But if you don't know after balancing and thinking all is good. Your BMS wont balance or protect the batteries. (not sure if this is normal Behavior) just my experience.
You could have pulled the balancing wire out of the bms instead of soldering en 2nd one to it! Tip for your next balancecharge with thw rc charger. Have a good one m8 love your work.
If you give this repack tool more cells than you need in the pack the capacity will be way closer as it's going to discard cells that aren't good for the pack
You can tell Repackr.com to rerun it's algorithm on your list of cells and it will produce a slightly different sort result each time. So if the divergence is more than you like in the first result - you can just rerun the sort and (maybe) get a very slightly better result. The backend code uses a cool software technique called simulated annealing: en.wikipedia.org/wiki/Simulated_annealing
Great information but felt like you fast forwarded past the more difficult parts at the end. Maybe I missed a previous video where you showed the end of the build.
Friend good night, what brand of BMS would you indicate to make a bank of batteries ?? Thank you, I'm from Brazil and I'm following your channel. Although here in Brazil electric car are very rare!
So the rated drain of a battery doesn't affect capacity if the amperage isn't pushed? Like I can use a 20c 2500mah battery with a 10c 2500mah battery if I'm not exceeding 10c per cell? They'll discharge at the same rate?
Which video of yours go over making this type of battery pack from start. Also do you have a video to understand bms boards vs no bms board? Thanks for what you do too. I've watched several of your videos!
I've been following your vlogs for some time and a month ago I wish I had seen this one.. But to be honest, I've done a better job than this site! 6s7p separated by 3mAh, yes, three!! 17735mAh /35/36/34/37/33 and 36.. Done the mats myself and I couldn't be prouder and happier :) Keep up teaching! Appreciate all your work.
I got quite some 18650 battery’s from battery packs, but i always use LGHG2 3000mA for my vaper, these battery’s are the battery’s ever made, it asks a-lot of current draw, and you recognize a good battery with this vaper! When the battery is empty, it immediately stops! If you draw it in a schematic, the curve line goes immediately to zero, with bad produced battery’s the curve line goes slowly to zero amps, which is quite annoying though. You will find these battery’s in good quality electric drills etc. They keep their full, and it immediately stops when their empty. This whole story takes me to this. When I charge a battery from a accu pack.. charged it for 2200mA or so, but when i fire it up, a lil’ fluffy cloud comes out for a second. So this is a good indicator to test a current load. I learner this is on my from a old skool repair man, he said when a battery is fully charged it won’t tell anything! When he putted a watt meter on it, you see the current drops so fast, that the battery is unusable en go straight to the dumpster! I haven’t got a single battery from a pack which can hold up with my vaper.. So those battery’s are quite bad, I think they do… Maybe in a battery pack, but i really dunno. But putting a load on it it will immediately tell you something, so i guess you can skip leaving the battery’s to wait for a few weeks. But you can test this by comparing. If so leave the whole storing technique lol I have some other question also… What it is the cheapest method to discharge.. lol a resistor, but safely discharge, so it dusn’t goes under voltage!
I did some measurements on my work.. I tested 2 batteries from packs and 1 Good battery LGHG2 with a wattage meter They all measured 3 watts, but when i added a voltage meter also i saw a big difference! The HG2 stayed on voltage, while 2 other 2 battery’s had a continuing voltage drop 🤓 This kinda explains why those battery’s didn’t work i my vaper. It wasn’t capable to provide a steady load. I vape at 50 watts with 0.18 coil/resistor so if you do the math you will have current load of 16.6 amps @ 3volts, my vaper goes up to 75watts and with a 0.18 coil it pulls 20.4 amps current @ 3.68v the HG2 supports 20amps so i know that the battery is healthy when i use it in my vaper.. This is like the most extreme current draw you can do. It might be handy to get datasheets of each battery you have to see what current draw they have, and with an ohms law calculator you can easily calculate resistors en very important how many watts a resistor must be, because the can get hot though. If you do some research and buy some resistors to duplicate load en put a voltage meter on to see if the voltage drops, you see it’s a bad battery… But maybe those battery’s will work in a pack, due the volume, but the current draw would be way less then when you have non healthy battery’s. If you have healthy battery’s in it you have a killer pack though! But with this info given, you can design your own current load test with a few resistors, a broke charger to test/hold the battery and a cheap voltage panelmeter to check for the voltage drop. Try s different loads also, maybe with 0.1amp load the voltage drop stays steady? Ohm law calculator is your big friend in this
With a 5.6ohm 5watts resistor you have a current draw at 0.73amps & 4.1volts @ 3watts It’s about doing the math, testing different setups and take note’s
Maybe a warning notice, if you work with healthy battery that can deliver let say 20amps each battery and you will have 56 in it, it’s like 1120 amps!! That it sum high current no to fuck with tho, if you got a short maaan you get fireworks, you gotta do sum real serious wiring lol with those healthy ones… Nuff said i hope you can do something with all the info i gave Btw i dunno if the amps go down if put them in serie, parallel i never work with that stuff
Maybe a good tip to buy cheap healthy battery’s, company’s who sell new ones regularly get packs back due all kinds of reasons, they can’t sell them as new, they are tested as healthy one’s and you can get them quite cheap tho, may be even cheaper is you disassemble yourself
Maybe another idea for a adjustable current loader is to buy an istick pico 75watt mod, make it so you use an old broken charger to hold the battery in, otherwise it’s a pain to test many battery’s, may use a higher ohm coil, or make custom, it’s just a twisted a wire. Add a voltmeter Voila you have a adjustable current/battery tester. Might be handy to check at which rate the current draw, the voltage stays the same… Then with ohms law you can calculate the current. But maybe the is a cheap pcb also which has the same functionality… google is your friend in this! Cheers & good luck
Don't just run with the first numbers RePacker comes up with. You can do a lot better if you do one run and then substitute the Flyers with better batteries and run the numbers a few more times like that. With a few runs you can get the Deviation number down quite good.
Can you use electrical conductive paste adhesive (silver content) to connect the batteries instead of wiring? Have you tried this? And what was the result for you? Thanks
Hey jehu You can buy spotwelders really cheap on aliexpress (150$). Please try one out. I think it would be worth it because you make so many battery pacs. You can also buy the wire wich is used on the resistor legs.
Just used repakr for my first 3s 10p pack , take a look in RUclips for it with fuses and in a coke bottle lol so I can see when fuses blow if they ever do lol
I'm surprised you are not adding Super Capacitors to these setups. They can store energy for a long period of time and some are using them in place of a 12Volt car battery. One guy left his car at the airport for a long time, it still started when he got back using the Super Capacitor's as well as a LiPo square cell with it as well.
I just thought for some storage it might work well adding some Super capacitor's, you can buy them for Audio Systems for your car for around $400 USD. Check out the guys using Super Capacitor's in place of the car's battery, it stores electricity longer without going dead unlike a Lead Acid battery which all cars are using.
Hello, do you have to be careful about the internal resistance of recycled li ion cells? Only use the ones which values are close to one another or it doesn't matter? Because some bms are designed to ballance new cells and those cells have pretty much same internal resistance? Greetings.
Great intro to making cell packs! Also, repackr[dot]com is a fantastic source. I hope this video means you're back on You Tube(?). My lack of experience with BMS boards won't allow me to do a video on the subject, but it would be a great service to the community if someone did a review of the various boards out there, especially for small packs. For power walls, Batrium seems to have the market sewn up.
Jehu, I have a weego Whip electric car with 630 miles on it. The battery is dead. Do you have an alternative to the old batteries that I could swap out ? Thank You. Mike
Jehu, Love watching your videos 👍 I want to make my packs modular like you have for my powerwall. My question relates to the BMS for each pack. I was planning on 7s10p packs/modules, with 7 of these modules in parallel to dictate overall capacity. The plan is to set up in a way that I will never draw more than 0.5a from each cell. In your opinion what amp rated BMS do you think would work best for each module?
if i have 1000 cells in each 3.6volt pack will i need to do this if all of my cells are between 2400mah and 2700mah? total battery size is 7s1000p. how forgiving is the capacity on large power walls. or should i very carefully balance each pack by tested mah?
What part of the pack do the leads go? does the minus go on the lower capacity side of the pack and positive go on the more capacity side or vice versa. do the leads need to be on same side of pack or opposite or is that a matter of preference? please let us know
Bro, thanks for telling us what's up with BMS/balance devices from on line sellers. I finished my 7 kwh powerwall-clone 6 months ago, without BMS's. I buit it from the 1S 20P packs that you used in one of your other powerwalls. They are all closely matched in capacity. I have since been trying to find BMS's to make it more balanced. I have bought 5 or 6 BMS's from different manufacturers, and have not found ONE that works 100% correctly. mierda pura
Hi jehu i want to know when I charge my batteries they drop in voltage a little say 4.14v or around there is that normal they stay at that voltage and dont self discharge im just wanting to know if that's normal
Dude what do you do with all of those batteries in your house?? Just charge and discharge them all day? Please tell me you are using them to help power your home or something.
this only really applies for recycled 18650's. new ones from a TRUSTWORTHY source should be good, but if you buying chinese stuff you should test anyway.
@Victor Guillen - It is much better to find out that you have bad cell BEFORE you build the entire pack, because then you need to dis-assemble and re-assemble the entire pack ...
Hi Jehu, thanks for another awesome vid. I wondering how relevant the accuracy is. Lets say you want to increase battery life and only charge to 4V and discharge to 3.2, looking at the discharge curve of an average cell that will give you about 10% less capacity but will increase cell life dramatically. When you test the cells you are dependent on the cutoffs from the charger, which will probably be on a larger range then what you would ideally want. I get it that you dont want to put cells 500 mah apart together but given that there is an error on the capacitytester(is there, have you ever tested one cell 10 times to see what the sd and variance are?) It feels like an overkill because there is an inherent uncertainty with these cells. What do you think? Thanks for the awesome channel!
Would like to do Lithium Ion, the range on the old batteries was only 40 miles. I would like to talk to you about buying a set of batteries from you if you are interested?
I have cells between 1700 to 2200mah capacity. can i use this tool to make battery pack out of them ? is this range safe or i should compact the range further please guide anyone
those number come from the Battery tester, you can get a Zanflare, or OPUS BT-c3100 and it will give you the internal resistance and the capacity ...there are many more bu that is what I have... I like the Zanflare the best...
Hello. Thank you for creating this video. But I'm a little confused. You say 24v with 7s. But in other videos you say 3s is 12v, so 6s would be 24v.? So 7s would be ~28v? What am I missing? Cheers
every liion cell is 3.7v. so 3s is actually 11.1. 7s is 3.7 x 7 = 25.9. if you would use 6s you get 3.7 x 6 = 22.2. neither of these is perfect, so you can pick the one most suited for your application.
just starting here... my idea is 48v and have an "ever growing" powerwall (once is big enough, additional packs would work as replacement of "bad ones")
He's talked about this dilemma in a few live feeds. For himself he prefers to start with well matched cells and then monitor the battery himself. But if he's building something for other people who may not monitor the battery then it's probably better to go with a BMS. Also - the need for balancing decreased as the number of cells in parallel increases. For a "small" 5P pack it's worth having a BMS (and try to get a reasonable quality one - not a super cheap one).
Me and some friends are building an electric go kart using 18650s, this is going to be very useful! Thanks for all the great work and videos you're doing on the topic.
As always you make everything so clear. I wanted to find out the reason why I have to match the mAh of each battery and here it is.
Damn ! I was thinking it was going to be pain in the Rump to Calculating what batteries would give me equal Cell Capacity. That Program took away the Pain. Thank You !
that program does a similar task to the programs used by the airlines to calculate weight and balance for aircraft, to know how to load the baggage, and balance the aircraft, while making sure that the weight estimate is accurate. interesting. your channel is valuable as always! thanks, Jehu!
Great vid, suggest picking up any random battery then place it in the row it was assigned by the repacker
I have built several packs and never use a BMS. They always fail and are a pain in the butt! I charge my packs every time with a nice hobby balance charger. The 52v packs I build are split into two 7S packs. I then charge each 7S with my dual 8S balance hobby charger. I believe investing in a good hobby charger will out way all the bad BMS issues I will have to deal with in the future. Plus the hobby charger allows me to monitor cell voltage and resistance which helps determine the over all health of the battery.
Well, you are using the BMS ( balancer ) that is built-in to the Charger. You have no BMS when discharging ...
Nice reference to the rePackr utility. That helps a lot. I enjoy your battery videos on RUclips most. The LIVE streams can be fun, but not normally as informative for me.
The builder tool is easy to use, spot welding was harder than expected, I built a 7s 15p pack (I wanted to charge 1 amp per cell) ended with a 932wh pack, still have to test to build another one. This video helped.
That tool should add a way to enter both capacity and resistance so you can build a pack that not only stays balanced during slow discharge, but also won’t let one brick sag excessively during high discharge. Sort of like one of your old videos shows how to do by manually grouping the cells and getting the high drain and low drain cells equally distributed while getting the total capacity of each brick as close as possible.
And man I wish you had a step by step video. Looks pretty good.
I legit just made this pack lol watching this video on super slowmo didn’t know how to connect the balance leads so this was a great video on that ….your the goat 🐐 🙌🏽🙌🏽🙌🏽🙌🏽🙌🏽🔋🔋🔋🔋🔋🔋👑👑👑👑👑👑👑
18650 battery that always intrigued me😁🇮🇩
6:47 programming tip: if you want to find the cells faster, just sort them first
Thanks again for keeping us all inspired to keep recycling. It was great to see you having a good time on holiday also :)
Can you put link for one of your videos, a slowed down dummy step by step version that shows me how to build a 36x 18650 batteries 12v pack. Or something similar. Or if you have a step by step video on how you built your Puerto Rico Emergency power case. I would appreciate it. Love your videos man! Keep up staying up.
Love your production values. Music/Editing. Nice work :)
You SHOULD charge the cells first and leave them alone for a number of weeks and see which ones self discharge to weed out the bad ones. Capacity checking isn't enough otherwise you end up with a pack that keeps discharging itself.
I think he assumed you did that already. There are other videos that walk you through testing and sorting of the cells
Phizicks the cells that self discharge would not be holding 80% capacity. Especially since the cell analyzers calculate discharge capacity. I guess if these cells were originally 2600mah and reading 1400mah then there could be a self discharge cell but if these are 1600mah cells new and reading 1400mah now there's no self discharge. That means the anode is shorted with the cathode.
Tom Amerman i have seen many cells holding close to new capacity and still self discharging. Roughly up to 0.5% off all my tested cells have had that phenomen. Of course depends on source of the cells.
What about Restances??I have also seen the same but was able to catch this with Resistance testing. I like to resistance tested every cell, looking for the higher ones. those I typically find will self-discharge pretty fast compared to the other cells. Some people instead of resistance testing will just charge a cell and if it falls below 4V, they consider it bad. I have seen cell at almost full capacity, self-discharge with high resistances. Also if you have a cell with high resistance, and you try a measure the capacity by charging, instead of discharging, and you use something like 0.5amps. You will get a much higher Capacity than the other cells. Typically easy to find, based on them measuring 2800mah and the cell is actually 2600mah. The cell is discharging at the end of the charge faster than the charger cycles.(but I am a newbie, and these are just my experience with salvaged cells.)
Still a great Video, but my only worry is using Brass strips, instead of copper? I thought this was a no-no? I had always thought he used copper?? I can find brass strips all day long at my local hardware store, just not copper. I have to make those myself.
Did you put a load it? Like a watt meter? If you put a load on it and the current drops big time, 90% or more that the battery is dead though
Nice video , best that I’ve seen on the net ..
Excellent explanation 👍
Back to the basics, I have to do a 7S-12P , I have a 7S windows-android BMS to test on it and I am going to try a Buck-booster to give me 12-14.5V for my 5th wheel LED Lighting Circuit :)
Btw, instead of the little resistors you can also just use wire on a spool. Copper, silver or other types of wire would work just fine.
Yeah curious. Or just buy fuse wire. It really is an aspect that "smells" a little about this channel. It would be nice to have a video on how to precisely calculate the needed wire length and gauge for a certain battery pack instead of guesswork.
I mean it can be done.
What do you mean by calculate? It's a matter of a few simple physics laws about wire length, resistance and dissipated power -> heat?
Or the simple version, look what companies use and use that as well. A little to big never hurts.
Well yeah, that's what I mean. It should be simple calculation if you know how (I don't know how).
www.powerstream.com/Wire_Size.htm
I guess you could use the chassis wiring current load limit, which would make 23 or 24 AWG seem appropriate for use as fuse wire in a bus bar. This is assuming soft annealed, nickel-free, solid core wire.
I think the idea is the resistors are easier to handle when you have to do the job a lot.
I found if you line up your cells lowest to highest mah it's easy to find each cell you need
I've been waiting for a tool like this. This will save a lot of time.
Thank you for mentionning this great tool.
Another Great Video! I like to add a balance cables along with the BMS, just incase I have to balance charge later. You have to be careful when using a BMS and Balancing if you have a charger that does more than .5amps per cell. If your charger does more than .5 amps, sometimes it will trip the protection circuit and cause the BMS to fail, unless you reset it with no charge. Some will allow you to just add a charge and it reset. But if you don't know after balancing and thinking all is good. Your BMS wont balance or protect the batteries. (not sure if this is normal Behavior) just my experience.
Really useful, thanks! Going to try making a small pack for kids' electric car, this is exactly what I was trying to figure out :)
Very nice I think I will like that repackr site
You could have pulled the balancing wire out of the bms instead of soldering en 2nd one to it! Tip for your next balancecharge with thw rc charger. Have a good one m8 love your work.
Algún día nos tendrás que explicar todo tu montaje y tu powerwall , un saludo desde España
Dude. You're a life saver. That app is awesome.
If you give this repack tool more cells than you need in the pack the capacity will be way closer as it's going to discard cells that aren't good for the pack
Sweet, I didn't know it did that! I'll definitely try that next time I'm building a pack!
I was surprised at how well the program could balance the cells.
Well that changes everything considering he has an official shit ton of batteries. I would also try to pick out ones that were closer to begin with.
The Algorithm chooses the Highest Capacity Cells to start with. It would be cool if they included a Bubble Sort program you could use as well.
You can tell Repackr.com to rerun it's algorithm on your list of cells and it will produce a slightly different sort result each time. So if the divergence is more than you like in the first result - you can just rerun the sort and (maybe) get a very slightly better result. The backend code uses a cool software technique called simulated annealing: en.wikipedia.org/wiki/Simulated_annealing
Great information but felt like you fast forwarded past the more difficult parts at the end. Maybe I missed a previous video where you showed the end of the build.
Love the new intro and the ending
Friend good night, what brand of BMS would you indicate to make a bank of batteries ??
Thank you, I'm from Brazil and I'm following your channel. Although here in Brazil electric car are very rare!
So the rated drain of a battery doesn't affect capacity if the amperage isn't pushed? Like I can use a 20c 2500mah battery with a 10c 2500mah battery if I'm not exceeding 10c per cell? They'll discharge at the same rate?
Great video! I'll be interested to know how that little BMS does.
Which video of yours go over making this type of battery pack from start. Also do you have a video to understand bms boards vs no bms board? Thanks for what you do too. I've watched several of your videos!
I've been following your vlogs for some time and a month ago I wish I had seen this one.. But to be honest, I've done a better job than this site! 6s7p separated by 3mAh, yes, three!! 17735mAh /35/36/34/37/33 and 36.. Done the mats myself and I couldn't be prouder and happier :)
Keep up teaching! Appreciate all your work.
I got quite some 18650 battery’s from battery packs, but i always use LGHG2 3000mA for my vaper, these battery’s are the battery’s ever made, it asks a-lot of current draw, and you recognize a good battery with this vaper!
When the battery is empty, it immediately stops!
If you draw it in a schematic, the curve line goes immediately to zero, with bad produced battery’s the curve line goes slowly to zero amps, which is quite annoying though. You will find these battery’s in good quality electric drills etc. They keep their full, and it immediately stops when their empty.
This whole story takes me to this.
When I charge a battery from a accu pack.. charged it for 2200mA or so, but when i fire it up, a lil’ fluffy cloud comes out for a second. So this is a good indicator to test a current load.
I learner this is on my from a old skool repair man, he said when a battery is fully charged it won’t tell anything!
When he putted a watt meter on it, you see the current drops so fast, that the battery is unusable en go straight to the dumpster!
I haven’t got a single battery from a pack which can hold up with my vaper..
So those battery’s are quite bad, I think they do…
Maybe in a battery pack, but i really dunno.
But putting a load on it it will immediately tell you something, so i guess you can skip leaving the battery’s to wait for a few weeks. But you can test this by comparing.
If so leave the whole storing technique lol
I have some other question also…
What it is the cheapest method to discharge.. lol a resistor, but safely discharge, so it dusn’t goes under voltage!
I did some measurements on my work..
I tested 2 batteries from packs and 1 Good battery LGHG2 with a wattage meter
They all measured 3 watts, but when i added a voltage meter also i saw a big difference!
The HG2 stayed on voltage, while 2 other 2 battery’s had a continuing voltage drop 🤓
This kinda explains why those battery’s didn’t work i my vaper.
It wasn’t capable to provide a steady load. I vape at 50 watts with 0.18 coil/resistor so if you do the math you will have current load of 16.6 amps @ 3volts, my vaper goes up to 75watts and with a 0.18 coil it pulls 20.4 amps current @ 3.68v the HG2 supports 20amps so i know that the battery is healthy when i use it in my vaper..
This is like the most extreme current draw you can do.
It might be handy to get datasheets of each battery you have to see what current draw they have, and with an ohms law calculator you can easily calculate resistors en very important how many watts a resistor must be, because the can get hot though.
If you do some research and buy some resistors to duplicate load en put a voltage meter on to see if the voltage drops, you see it’s a bad battery…
But maybe those battery’s will work in a pack, due the volume, but the current draw would be way less then when you have non healthy battery’s.
If you have healthy battery’s in it you have a killer pack though!
But with this info given, you can design your own current load test with a few resistors, a broke charger to test/hold the battery and a cheap voltage panelmeter to check for the voltage drop.
Try s different loads also, maybe with 0.1amp load the voltage drop stays steady?
Ohm law calculator is your big friend in this
With a 5.6ohm 5watts resistor you have a current draw at 0.73amps & 4.1volts @ 3watts
It’s about doing the math, testing different setups and take note’s
Maybe a warning notice, if you work with healthy battery that can deliver let say 20amps each battery and you will have 56 in it, it’s like 1120 amps!! That it sum high current no to fuck with tho, if you got a short maaan you get fireworks, you gotta do sum real serious wiring lol with those healthy ones…
Nuff said i hope you can do something with all the info i gave
Btw i dunno if the amps go down if put them in serie, parallel i never work with that stuff
Maybe a good tip to buy cheap healthy battery’s, company’s who sell new ones regularly get packs back due all kinds of reasons, they can’t sell them as new, they are tested as healthy one’s and you can get them quite cheap tho, may be even cheaper is you disassemble yourself
Maybe another idea for a adjustable current loader is to buy an istick pico 75watt mod, make it so you use an old broken charger to hold the battery in, otherwise it’s a pain to test many battery’s, may use a higher ohm coil, or make custom, it’s just a twisted a wire. Add a voltmeter Voila you have a adjustable current/battery tester.
Might be handy to check at which rate the current draw, the voltage stays the same…
Then with ohms law you can calculate the current.
But maybe the is a cheap pcb also which has the same functionality… google is your friend in this! Cheers & good luck
Don't just run with the first numbers RePacker comes up with. You can do a lot better if you do one run and then substitute the Flyers with better batteries and run the numbers a few more times like that. With a few runs you can get the Deviation number down quite good.
Can you use electrical conductive paste adhesive (silver content) to connect the batteries instead of wiring? Have you tried this? And what was the result for you? Thanks
Hey jehu
You can buy spotwelders really cheap on aliexpress (150$). Please try one out. I think it would be worth it because you make so many battery pacs. You can also buy the wire wich is used on the resistor legs.
Jehu has other videos on using the spot welder. I think he owns one or two of them
Gerald Grogan but why is he then soldering?
ruclips.net/video/O9c8VrCuCwo/видео.html
I just did 1120 cells with cell pack man that was tedious., painful and took me all day. Lol
Exactly what im up to on my channel your an inspiration
Just used repakr for my first 3s 10p pack , take a look in RUclips for it with fuses and in a coke bottle lol so I can see when fuses blow if they ever do lol
I'm surprised you are not adding Super Capacitors to these setups. They can store energy for a long period of time and some are using them in place of a 12Volt car battery. One guy left his car at the airport for a long time, it still started when he got back using the Super Capacitor's as well as a LiPo square cell with it as well.
These don’t need capacitors, batteries work better at storing energy
I just thought for some storage it might work well adding some Super capacitor's, you can buy them for Audio Systems for your car for around $400 USD. Check out the guys using Super Capacitor's in place of the car's battery, it stores electricity longer without going dead unlike a Lead Acid battery which all cars are using.
@@cuddles6938 How do Super Caps make this battery pack "better" ? They add too much cost ...
I wish u have more detail info..while building pack..
Cual es tu duda amigo? (What is your doubt friend?)
Watch his other videos idiot 😂
Sir, where can i buy a 7s bms you used in your battery pack? 🙏🙏✌️✌️
Hello, do you have to be careful about the internal resistance of recycled li ion cells? Only use the ones which values are close to one another or it doesn't matter? Because some bms are designed to ballance new cells and those cells have pretty much same internal resistance?
Greetings.
Great intro to making cell packs! Also, repackr[dot]com is a fantastic source. I hope this video means you're back on You Tube(?). My lack of experience with BMS boards won't allow me to do a video on the subject, but it would be a great service to the community if someone did a review of the various boards out there, especially for small packs. For power walls, Batrium seems to have the market sewn up.
I never stop making RUclips videos
making vids with loads of views makes you more money lol
Jehu, I have a weego Whip electric car with 630 miles on it. The battery is dead. Do you have an alternative to the old batteries that I could swap out ? Thank You. Mike
pretty sure you can build it
hii, what about resistance? As far as i know it has to be very precise, otherwise it affects the equalization of the cells.
Can you use any capacity cells with this? Or you need to stay close even with this repackr way?
Hi, What is the best 18650 battery out there right now? I want to tinker and learn to build my own system.
Jehu,
Love watching your videos 👍
I want to make my packs modular like you have for my powerwall. My question relates to the BMS for each pack. I was planning on 7s10p packs/modules, with 7 of these modules in parallel to dictate overall capacity. The plan is to set up in a way that I will never draw more than 0.5a from each cell. In your opinion what amp rated BMS do you think would work best for each module?
if i have 1000 cells in each 3.6volt pack will i need to do this if all of my cells are between 2400mah and 2700mah? total battery size is 7s1000p. how forgiving is the capacity on large power walls. or should i very carefully balance each pack by tested mah?
What part of the pack do the leads go? does the minus go on the lower capacity side of the pack and positive go on the more capacity side or vice versa. do the leads need to be on same side of pack or opposite or is that a matter of preference? please let us know
Should i use a bms when building a battery for a car? And if so how many would i need
Please tell me can I use fully charged 4.2 v cells in the pack or have to discharge them to 3.7v .. as I don't have discharger
Love your work Jehu. Keep it up brother.
Bro, thanks for telling us what's up with BMS/balance devices from on line sellers. I finished my 7 kwh powerwall-clone 6 months ago, without BMS's. I buit it from the 1S 20P packs that you used in one of your other powerwalls. They are all closely matched in capacity. I have since been trying to find BMS's to make it more balanced. I have bought 5 or 6 BMS's from different manufacturers, and have not found ONE that works 100% correctly. mierda pura
Barry Taylor One word: Batrium.
or check out the diyBMS if you dont mind getting your hands dirty soldering it.
Mar Eck do you have a link or info to diy bms?
Hi jehu i want to know when I charge my batteries they drop in voltage a little say 4.14v or around there is that normal they stay at that voltage and dont self discharge im just wanting to know if that's normal
is it me or did he just cut video short. I wanted to see how he charged and test the pack
Is it still ok to use the Nickel 18650 strip instead of the brass strip?
Dude what do you do with all of those batteries in your house?? Just charge and discharge them all day? Please tell me you are using them to help power your home or something.
That is fantastic jehu
rePackr is awesome!!
Should I check the battery even if I buy brandspanking new 18650s??
this only really applies for recycled 18650's. new ones from a TRUSTWORTHY source should be good, but if you buying chinese stuff you should test anyway.
@Victor Guillen
- It is much better to find out that you have bad cell BEFORE you build the entire pack, because then you need to dis-assemble and re-assemble the entire pack ...
Hi Jehu, thanks for another awesome vid. I wondering how relevant the accuracy is. Lets say you want to increase battery life and only charge to 4V and discharge to 3.2, looking at the discharge curve of an average cell that will give you about 10% less capacity but will increase cell life dramatically. When you test the cells you are dependent on the cutoffs from the charger, which will probably be on a larger range then what you would ideally want. I get it that you dont want to put cells 500 mah apart together but given that there is an error on the capacitytester(is there, have you ever tested one cell 10 times to see what the sd and variance are?) It feels like an overkill because there is an inherent uncertainty with these cells. What do you think? Thanks for the awesome channel!
Would like to do Lithium Ion, the range on the old batteries was only 40 miles. I would like to talk to you about buying a set of batteries from you if you are interested?
I dont sell batteries, but my friends do
j35.us/May-3daySALE
j35.us/May-7Day-SALE
j35.us/LargeEV-battery-Modules
Where would i get 18650 for cheap in INDIA
i'm planing to mix my 4 2200mah with 1 2150mah to make 21v is the Okay?
You are a hero man,keep up with the good work.za
Where can I her those brass strips or can I use something else to weld them together
Hellow sir may i ask
Can i join 2100mah and 1500mah in same pack?
Awesome!
That went over my head...... Whoosssh
Hello can you answer for me please
I have cells 3.7v end 3.6v from samsung
Can i use together to build One battery
Wow man nice job on lettings us know about that site it well be very useful in the furture when i plan on making packs thanks alot
good day i have Lishen (LS) LR1865SF Cell which bms can i use
Hi Mr. Garcia! which bms would you recommend for a 20s20p pack?
i see use have the green ming he solar charge controller. do you know its hidden setting to auto start after power disconnects?
What is K & S brass strip model? Is it #8245?
8230
.41mm x 6.35mm = .016" x .25"
I have cells between 1700 to 2200mah capacity. can i use this tool to make battery pack out of them ? is this range safe or i should compact the range further please guide anyone
Hey Juhu onme thing how in the heck did you get the Bus bar on the the side without falling off?
:'))))
How do I know which cells are flipped negative up and then positive down?
How would I get those 4 digit numbers to enter in website. Thanks. And do they all have to be similar or close to similar voltage.
those number come from the Battery tester, you can get a Zanflare, or OPUS BT-c3100 and it will give you the internal resistance and the capacity ...there are many more bu that is what I have... I like the Zanflare the best...
Hi , How did you manage Dead cells?
10/10 so much info!!!!!
Sir, this battery pack you made, the issues I have always have with them is how to charge them.
Hello. Thank you for creating this video. But I'm a little confused. You say 24v with 7s. But in other videos you say 3s is 12v, so 6s would be 24v.? So 7s would be ~28v? What am I missing? Cheers
every liion cell is 3.7v. so 3s is actually 11.1. 7s is 3.7 x 7 = 25.9. if you would use 6s you get 3.7 x 6 = 22.2. neither of these is perfect, so you can pick the one most suited for your application.
Thank you ! Great teacher !
hi you didnt check the internal resistence of each cell while making pack. Isn't it Important ??
Hello all right friend, what do I do with batteries that heat up a lot
Send to the recycler ...
Thanks! Used this tool for a ebike 13s6p pack. For powerwall modules, would 35 cells (7x5) as you have it here be the recomended pack size? Thanks!
Depends what you want to power, and the scheme you want run your battery at
just starting here... my idea is 48v and have an "ever growing" powerwall (once is big enough, additional packs would work as replacement of "bad ones")
You changed your mind about Bmss
Which is dispointing cause im planning to build a pack without it.
What makes you change your mind
He's talked about this dilemma in a few live feeds. For himself he prefers to start with well matched cells and then monitor the battery himself. But if he's building something for other people who may not monitor the battery then it's probably better to go with a BMS. Also - the need for balancing decreased as the number of cells in parallel increases. For a "small" 5P pack it's worth having a BMS (and try to get a reasonable quality one - not a super cheap one).
Hi is Russia, Привет из России
But you must say- HI from Russia!
Can i use 2000×15=30000mah for one parallel, 2500×12=30000mah for other parallel 3000×10=30000mah for one more parallel in 13s battery pack
Can we enclose this battery pack in wodden container
You rock man!