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 !
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.
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.
Nice reference to the rePackr utility. That helps a lot. I enjoy your battery videos on UA-cam most. The LIVE streams can be fun, but not normally as informative for me.
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 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 🐐 🙌🏽🙌🏽🙌🏽🙌🏽🙌🏽🔋🔋🔋🔋🔋🔋👑👑👑👑👑👑👑
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.
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.
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.
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.
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.
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 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.
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 :)
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 ...
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!
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
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?
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
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.
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!
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.
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
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
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?
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...
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
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
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 UA-cam for it with fuses and in a coke bottle lol so I can see when fuses blow if they ever do lol
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.
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")
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
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?
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 !
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 ...
Great vid, suggest picking up any random battery then place it in the row it was assigned by the repacker
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.
Nice reference to the rePackr utility. That helps a lot. I enjoy your battery videos on UA-cam most. The LIVE streams can be fun, but not normally as informative for me.
Thanks again for keeping us all inspired to keep recycling. It was great to see you having a good time on holiday also :)
6:47 programming tip: if you want to find the cells faster, just sort them first
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!
Love your production values. Music/Editing. Nice work :)
And man I wish you had a step by step video. Looks pretty good.
Thank you for mentionning this great tool.
I've been waiting for a tool like this. This will save a lot of time.
Nice video , best that I’ve seen on the net ..
Excellent explanation 👍
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 🐐 🙌🏽🙌🏽🙌🏽🙌🏽🙌🏽🔋🔋🔋🔋🔋🔋👑👑👑👑👑👑👑
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.
18650 battery that always intrigued me😁🇮🇩
Dude. You're a life saver. That app is awesome.
Really useful, thanks! Going to try making a small pack for kids' electric car, this is exactly what I was trying to figure out :)
Great video! I'll be interested to know how that little BMS does.
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.
Love the new intro and the ending
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
Very nice I think I will like that repackr site
I found if you line up your cells lowest to highest mah it's easy to find each cell you need
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.
Exactly what im up to on my channel your an inspiration
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.
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.
Love your work Jehu. Keep it up brother.
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.
rePackr is awesome!!
10/10 so much info!!!!!
You are a hero man,keep up with the good work.za
That is fantastic jehu
Awesome!
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 :)
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 ...
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!
Should i use a bms when building a battery for a car? And if so how many would i need
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
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
Algún día nos tendrás que explicar todo tu montaje y tu powerwall , un saludo desde España
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?
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
Can you use any capacity cells with this? Or you need to stay close even with this repackr way?
I just did 1120 cells with cell pack man that was tedious., painful and took me all day. Lol
You rock man!
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
Thank you ! Great teacher !
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.
Hi, What is the best 18650 battery out there right now? I want to tinker and learn to build my own system.
That went over my head...... Whoosssh
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!
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.
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
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
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 😂
Hey Juhu onme thing how in the heck did you get the Bus bar on the the side without falling off?
:'))))
hii, what about resistance? As far as i know it has to be very precise, otherwise it affects the equalization of the cells.
Where can I her those brass strips or can I use something else to weld them together
Is it still ok to use the Nickel 18650 strip instead of the brass strip?
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?
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...
Where would i get 18650 for cheap in INDIA
i see use have the green ming he solar charge controller. do you know its hidden setting to auto start after power disconnects?
Sir, where can i buy a 7s bms you used in your battery pack? 🙏🙏✌️✌️
Great video
What is K & S brass strip model? Is it #8245?
8230
.41mm x 6.35mm = .016" x .25"
Thanks for this!
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
How do I know which cells are flipped negative up and then positive down?
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
Hi Mr. Garcia! which bms would you recommend for a 20s20p pack?
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?
ua-cam.com/video/O9c8VrCuCwo/v-deo.html
i'm planing to mix my 4 2200mah with 1 2150mah to make 21v is the Okay?
good day i have Lishen (LS) LR1865SF Cell which bms can i use
Just used repakr for my first 3s 10p pack , take a look in UA-cam for it with fuses and in a coke bottle lol so I can see when fuses blow if they ever do lol
Hi , How did you manage Dead cells?
great video :D keep up the great work
Can we enclose this battery pack in wodden container
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
Hellow sir may i ask
Can i join 2100mah and 1500mah in same pack?
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.
hello Jehu , I need to make a pack 19s 40ah for my scooter I need to know how many cells do I need thanks
I think the 19 in 19s spells it out for ya there fella. As for the Ah depends on the capacity and rating of the batteries your using.
@jose r
- Do you have any cells in parallel ?
what is the best solder for that application?
Quality brand, ie Kester/MG Chemicals/Alpha, 63-37, RA type solder.
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")
So you use the resistor wire, not the resistor?
John Coloe ty thats a very nice answer!
What's a good charger
Kristian Taylor it’s a charger that works well. 🤔
Sir, this battery pack you made, the issues I have always have with them is how to charge them.
Hello all right friend, what do I do with batteries that heat up a lot
Send to the recycler ...
is it me or did he just cut video short. I wanted to see how he charged and test the pack
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
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
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 we bought the 10 pack of your PCB cardss would that be 7s10p?
or would it be 10p7s
and could you even use this tool for your PCB because eche individule 18650 Cell is actually in series?
Does it works when i use different capacities with BMS 2403 mah with 1974 mah batteries?
Can i have your email address in order to send you my pack photos ... i need your advice
what are exact kind of resistors???
What do you use to charge all that?