How To Make A Lithium Battery Pack With 18650 Cells | Practical Skills For Makers

[@bytesizedengineering]

Huge thanks to my *channel members* who make these videos possible. If you want to support what I do and get access to free project files, an awesome discord community, and much more, head over to *www.patreon.com/bytesizedengineering* or click the *join* button here on KZbin.

[@Dragon-Slay3r]

How about the huge battery pack?

[@Vmaxfodder]

Hello , I am making a 84v 23s or 24s that is 40 amp hour with 8 wide 21700 50s samsung . I am having a hard time figuring the total amps and watts ? What size BMS do I need ? Thanks

[@Neilukuk]

Do you know what the maximum mAH 18650 battery you can get?

[@chupacabra4897]

Can you use these to power a solar generator ?

[@Corona-k6z]

Werlke lassen apparaat gebruik je om te lassen?

[@mrhow2712]

You have to make sure the voltage is all the same before connecting batteries. Surprised he didn't mention something so important!

[@xXx-un3ie]

ikr and not even some thin gloves while soldering and spot wielding. Like if he touches it the wrong way he could get a up to 48V 48mA shock, assuming the skin has around 800 ohms resistance + up to 200 ohms for potential inner-body current flow. This is a bit away from the lethal area of 100mA-200mA but 48 volts with a good nice current can damage a lot depending on what it travels through(hope you dont have it travel from one finger to the opposite hand finger because every current flow near the heart is always reallllllllllly bad. Anyways, the batteries are able to do up to 30.000mA continous depending on brand and cell and should not be taken lightly especially when increasing the voltage and the watts like that.

[@FBI_Agent_]

Can't you build it all the batteries at 0% and charge them to 100%?

[@xXx-un3ie]

@@FBI_Agent_ They are never at 0%. Normally you should stop using Lithium batteries when they reach 2.5V. Anything less damages the battery inside because there needs to be a certain voltage to prevent the charge carrier from reacting chemically with each other. This is what you get then if something happens: the battery's insides react with each toher and produce heat, water, co2 and so on and might explode if the pressure gets too high. Also when charging you charge with 4.2V outer voltage up to 3.7V inner battery voltage. Anything over that has similiar effect as if you under-charge. So theoretically your 0% to 100% scale for batteries is jsut an area of volatge where it is safe to operate the battery and that is somewhere between 2.5 - 3.7V if you wanna be good to your batteries you make it narrower like 3.0 - 3.6V which also cuts away some capacitiy but prolongs the battery's life

[@FBI_Agent_]

@@xXx-un3ie Oh okay thank you that explains a lot.

[@asrielandcharadoesstuff4789]

Actually each cell has to be charged individually and balanced so if there's no BMS with multiple 18650s I don't think you're going to achieve the very good set up

[@HawkImagery]

the beat with the spot welding is a nice touch

[@michelkotoff-rizzo3112]

Loved this video. I went to school for electrical engineering and I never made the connection that building this sort of thing was this simple

[@mtherr]

When selecting battery cells, AH specification is important but it should be mentioned that continuous discharge current is equally important. Some cells can discharge at 20 amps rate while others will allow discharging at less than 3 amp rate. The current capacity of the nickel strips should also be considered. I also found out that not all BMS will balance batteries. Some are battery controllers that will protect from over discharge or charge and will not do the balance function at the end of the charge. I do like your videos.

[@LucasFurioFranco]

I learned to take into account the current capacity of the nickel strips the bad way... no damage was done, except for the nickel strip itself, but ooooh boy, it was beautiful! Frightening, but beautiful!

[@tariqbacchus]

Man watching you spot weld those pink lithium ion cells together was so satisfying to watch!

[@pandaexpresso]

thank you so much for doing the wire management around the bms. underrated step.

[@chuckraymond3564]

excellent job, I especially like adding combustion fuel rubber insulation. it will make overloading more exciting

[@HowTo2do]

Wow great tutorial on how to make battery pack from 18650 battery cells. Very professional work.

[@stafdehat]

Great video. Re: Affordability, it turns out that those 18650 cells can very often be found in old tool/laptop/etc battery packs, and very often, the pack itself is only bad because 1 of the 18650 cells in that pack is bad (parasitic). In those cases, people will throw away the whole pack, and you can dissect it to recover free, healthy (albeit used) 18650 cells. The downside there is that you need to test all your recovered 18650 cells individually, or suffer increased risk of fire/failure. Another youtube channel, "DIY Powerwall", has information on this. Also, tip: You can often use a Flir IR camera to identify which cell in your pack is bad, if/when that happens.

[@bytesizedengineering]

These are some awesome tips! Thanks for sharing! I've seen lots of videos of people recovering cells from used battery packs and that's a great way to reuse them instead of ending up in a landfill. It does require a lot of testing and making sure everything is balanced. Some of the cells may have lost their capacity over time and so you want to make sure everything is matched up.

[@scottbaker9066]

I rebuild packs with the ones that test 2.0Ah or more and if you have some that are 2.2Ah spread them out, like 1 in each group of 5. @@bytesizedengineering

[@richardisom4783]

Cool video, I've seen a few others about building a battery with BMS but your knowledge and background helped explain in more detail.

[@ExplainingTechTips]

Youre not gonna believe me but your channel deserves 10 million subscribers. When people dream of tinkering but dont know what to do or how to do it. Your channel doesnt show up for regular people I dont even know why I found it. What an amazing channel. I remember now I searched what is inside a 18650 battery

[@bytesizedengineering]

@@ExplainingTechTips I'm so glad you found my channel! You really hit the nail on the head. I know people have creative ideas in their minds, but they don't always have the ability to make them a reality. I want to help people unleash their inner makers.

[@ExplainingTechTips]

@@bytesizedengineering Thanks Byte size

[@forked-lightning]

Great video, first time viewer. I liked your production quality and how you went over the build and emphasized safety when appropriate.

[@tedhaas8440]

Looks great. The only problem with the insulating packaging you installed, is tho it insulates currents well, it also locks in the heat dissipation from each battery, thereby creating a tremendous amount of heat over time, which I'm sure you know how that effects longevity of the cells and changes in voltage output. Instead, I suggest coating the exterior of any exposed nickel plating, soldier joint and exposed wire ends with some non-conductive clear enamel paint, then when completely dry, install it into a non-conductive polymer/plastic electrical box, with a cooling fan on one side and a vent with a dust filter on the other side of the box to allow airflow to cooling the ambient air inside the box and to circulate the cooling air around each battery, then be vented out of the box, to help keep them cool and stable.

[@00TreadStone]

The best thing about a boat is that it keeps water out. The worst thing about a boat is that it keeps the water in. Well said.

[@bluestraveler2980]

I hope it doesn't rain.

[@brankelly1921]

​@@bluestraveler2980hahaha big time plot hole right here!

[@PatHaskell]

Love how people are always posting videos on a project that they have never done before.

[@craigrmeyer]

Thank you for sharing this. I know this is pretty basic stuff -- no Nobel Prizes here -- but still I appreciate being shown what this looks like in the flesh.

[@robr8554]

Very nice video showing the materials you used. Fantastic

[@awaitingthetrumpetcall4529]

I have wanted to build my own battery. Thanks for posting.

[@Will-of-all-trades]

Spot welds on beat! I dig it.

[@Daxlo]

Learned a few things, awesome video! Your foam shelf liner seems like a great idea from banging around protection. However, what I have learned rebuilding a commercial BH Bikes battery is about flame resistance: everything touching that battery will retard flame. You used Kapton tape -- good -- but over your shelf foam material, which is probably highly flammable. So the fire venting from a bad cell will hit your foam sheets first. I've seen videos where they use packaging tape too, which is flamey. The things in my BH bike's battery are: - Kapton tape, - Formex flame retardant PP sheets coated with sticky white silicone adhesive (I'm guessing here), - wiring harness tape (just bought a roll this super tough fabric tape-- goodbye duct tape!), - heat shrink tubing, and - whatever the plastic pieces used for structure, probably same thing you have. Also others have mentioned that your foam sheet traps the heat. I think maybe I might use narrower strips around all the corners and edges, outside the Kapton tape. Sorry I'm criticizing your Foam Shelf Liner choice, I don't want to start a *flame war*, haha!

[@BigCaseadilla]

Just came across your channel while trying to learn how to make my own board for a prototype of a product I want to make. Loving your videos so far!

[@Dtr146]

I bought one of those exact same battery welders. Works like a charm once you learn how to use it. I would suggest either attaching the two leads together by the heat shrink or printing a bracket to hold them together because it gets really cumbersome with the leads all loose

[@GlenDoer-gq1rs]

Name of welder?

[@r.b.l.5841]

they need to be loose touch only one first - to hold the metal tight to the battery then touch the seond terminal.

[@Dtr146]

@@GlenDoer-gq1rs It doesn't have a name. It's an aliexpress purchase. There's some better ones on the market right now that you can get for like 60 bucks.

[@Dtr146]

@@r.b.l.5841 I don't know about that. The two wires act as a button on the cheap ones. When the circuit detects that both leads are touching. It then activates the capacitor that is charged by the battery, which leads to the jolt that does the weld. You don't have to place one of the leads first. You just have to place both leads where you want to weld. Now, this may be different with other spot welders, or more expensive spot welders, but not this one.

[@r.b.l.5841]

@@Dtr146 Exactly, and if you touch both leads to the nickel before it is touching the battery you don't get a proper weld to the battery. Touch one terminal first to hold the nickel strip tight to the battery then touch the second terminal to initiate the weld.

[@majmaldcinformation]

Thank you very much sir I have learned a lot from your video the spot welding method of nickel stick using 18650 cell is very well explained thank you sir

[@Rustic_Farmer]

Love the spot welding to the beat of the music. Excellent stuff.

[@cmalc8]

Safer design is, after checking all the batteries for same voltage and grouped internal resistance, solder suitable fuse wire to thicker nickel strip bus bar and to thinner small squares of nickel, then spot weld the nickel squares to the batteries.

[@dankdigital4058]

Wow, this is so much fun I want to do this project so bad and I love your attention to detail. I'm the same way. My kind of guy subscribed thank you for the video.

[@christianwolf9314]

Thank you we need more videos like this hats off to you

[@baade6010]

270$ homemade vs 340$ store bought. thank me later :D

[@WarLord10]

Thank you already

[@Shmuelheart]

Wow thank you very much I learnt a lot from this video❤

[@benmerretz7200]

The one thing I really wanted to hear you talk about was sizing the BMS appropriately for the cells discharge rate. Can you comment please on the current requirements for your onewheel and why you chose the BMS you did?

[@BKMakes]

Congrats on the sponsorship…. …and the community loves the support Altium! I know where I’m going for my electrical design now👍🏻

[@bytesizedengineering]

Thanks! They have been a great sponsor of the channel

[@marksummers9543]

That was really fun to watch. Thanks for the info, I think I'll give it a go

[@TheEtbetween]

Thanks excellent, just bought a spot welding

[@WiredWorkshop]

Got here from the ILTMS discord, awesome project, that nickel plate made everything look super clean!

[@bytesizedengineering]

Thanks! Maker Alliance FTW!

[@dinacomp]

Man in 15 min video did the job that need at least one day

[@michaelkress3907]

I like that does make it look very professional I like the double bridges you got there for your series and parallel connection kind of a two and one good job

[@michaelkress3907]

You may point out that grid that you using is not just for holding him but spacing him to allow heat dissipation

[@TheLeontheking]

Always have a metal box (ideally with some sand in it) by your side when handling these cells. You'll be thankful if you can throw a burning one in there and close the lid :)

[@redcloverschoolhouse7501]

This is a great video! Very clear and informative. Thank you! 😁

[@Cactoos]

Really nice video, thank you for your work. I realize work itself takes time then cut video and edit it additional time so I do appreciate that, cheers

[@bytesizedengineering]

I'm so glad that it was helpful for you!

[@GlaucusBlue]

good work, my only advice is to cover the cells you aren't actively working on with Kapton or something else. Coming from experience, it only takes a single drop of something metallic too short. that looks like the exact same spot welder I have, which has been working great for years, albeit it is slow as leads heat up fast.

[@bytesizedengineering]

Even though I was being extremely cautious, I was unwinding some solder from the spool and it shorted out on some of the contacts. I didn't get it on camera unfortunately. That's a good suggestion to cover the other cells with tape.

[@michaelkress3907]

They make some very nice lithium iron cells

[@wizardmaster6639]

Great job - professional and secure when you make it yourself - simply because you know what kind of batteries you used and what is the TRUE capacity of each, not the claimed one by someone in China :) in voltage or in AH.

[@nixsy9]

thanks for making its really cool, like for your stuff

[@Grissinen]

Nice the cost compare, as you said, it makes sense to buy one because you have to calculate also your time / work / equipment and saving just 20% is not much... Thanks for your video

[@bytesizedengineering]

If your sole reason is cost, it doesn't make sense for most people to build your own. There are other reasons for building your own, like learning new skills and buying new tools.

[@jace_Henderson]

Unless you just love DIYing, yes, it isn’t worth it. I’m personally obsessed with electronics and engineering and DIYing and learning so for me this would make sense.

[@rodolfobaliga7577]

@@bytesizedengineering absolutely u are right bro.

[@nohphd]

IMO, while cost is important to me, building the pack gives you a tremendous amount of hands on, practical knowledge while just watching the video and then buying a pre-made pack, not so much. This may not be important today but down the road when you need to troubleshoot and repair the battery pack, the build experience is invaluable. Doubly important post zombie apocalypse!

[@kingmanL7309]

Now you can get them from Temu at much lower prices.😂

[@julianandyvonne]

Great video. Just what I needed. Have you tried repairing a 'broken' battery pack? I have a friend who's wheel has died. It's the same as mine but mine has done more than 10 times the distance! It's battery pack running at 126v. Two of the cells show that they have died in the BMS software. I couldn't find any 'repair' videos. Keep up the good work 👍

[@patrickmckowen2999]

Good build 👍 20% is not a lot of savings unless you are getting much better cells and BMS. Cheers

[@TiredOldMann]

Agreed. I can repair a 20 volt B&D 1.5 AH to 2.1 AH for $ 8.50 . Cheapest no name is $16 each if you buy two of them. Cost Matters !

[@dtvking]

Nice job spot welding those cells. Just a heads up on your next build, you should keep the balance leads all the same length so the resistance to the BMS is equal from each cell. Thanks

[@Vile_Entity_3545]

Hi I am collecting the small 3.7v 2.04wh 550 mah batteries from the new throw away vape sticks. I need 182 of them and is it possible to make a 48v battery for an ebike with them? 13 will make the 48v as you know. If I have 18 strips of 13 will I be able to wire them together? I still have a lot to learn how to wire them together properly but just want to know if it is possible to do.

[@tristanfloris9970]

Didn't think about this, thanks for the tip!

[@Devonto]

@@Vile_Entity_3545 it's possible, but not very practical.

[@michaelkress3907]

Sliding an additional piece of heat shrink of the two wires and the connector at the end will help reinforce the wire connections for when you connect and disconnect them it’s best they feel as one solid piece

[@carlotagliabue437]

Would you suggest using a 3d printed case for the battery pack that holds everything neatly, or is it better to go with heat shrink option? Beyond thermal compatibility of the plastic used, do you see any downsides or warnings?

[@rakkon1]

Great editing getting the wels sparks to line up with the tunes. Informative fast and concise. Suscribed thanks!

[@gunstargizmo]

I purchased an EBike with an unusual seat battery housing, so when the cells die, I'll have to replace them inside the housing because I doubt a replacement battery pack will be available at that time. I have good electronics experience, and this will help. Replicating the layout of the pack should make things easier.

[@gordonreason1069]

very good video .. but what is that blue shhrink wrap stuff called pse .

[@troytaylor1913]

Cool. I want to pack the bottom of a sealed plastic toolbox with 18650s but use a different BMS. It's got to keep my work campsite powered for a week. I figure I can weld plastic dividers using the same kind of plastic in places like for a true wave inverter, and a solar charge controller. I sell 18650 batteries for electronics that I sell so I have a trusted vendor I buy from. I have built a lot of small power banks for cell phones but this will be the first toolbox-sized 2000-watt bank. I also have a diesel heater that it has to power.

[@nicholaswitaszek5518]

How do you select the right battery management system. And when you charge it don't you use both leads the main lead for charging and then the other lead off of the BMS just to monitor the sell voltage?

[@user-ot1dv6ri4f]

I understand how you're putting them in series but the way you use that nickel strip to connect those 4 in parallel after that boggles the mind, it just looks like they are all connected together ??

[@IvanGOrtolan]

They are flipped around 🔼🔽🔼🔽

[@liljohnsonusmc]

Okay the sync of the beat and the spot weld was 💯

[@taylormoore4991]

Great video! God bless!

[@normanwray1341]

Hello dear friend I want watch you build that big battery 😊 thanks you sir

[@emaglott]

beautifully done and explained! thanks!

[@bytesizedengineering]

Thank you so much!

[@jariekstrom95]

do you have a circuit diagram of all battery connections?

[@lamarchedutemps7427]

Great TUTo. it look like my 9 year old Segway battery pack witch I plan to replace since I use this as a wheelchair, Tks !!! 🔔Subscribed

[@jasonlarkin3718]

Thank you for the video. I am building the same arrangement pack but with SAMSUNG 40T 21700 4000MAH 30A batteries. Would I need to find a BMS with a higher current rating? If so can you recommend one? I see some on Amazon, but all seem to have questionable reviews. Thank you!

[@bytesizedengineering]

I think the one I used had a current rating of 20A continuous. It totally depends on what you'll use it for. If you need higher continuous current then you'll need a BMS that can handle more. For my Onewheel build the built in BMS inside the battery pack has a rating of 50A continuous. If you need something like that, you'll just have to do some searching for BMS boards that can handle more current.

[@TechnologyGuru0000]

Very nice job done

[@mikehalvorsen4788]

Hi Zach. What if i wanted to build my battery pack upwards, and not a block? What i mean is i want to hide the batteries in a bike cylinder frame. Hard to explain... Would i have to use wires to connect each of the holders on the way up?

[@michaelkress3907]

Hi current Mosfet transistors are really expensive with a resistance of .012 ohms between the source in the drain Very little heat is generated but a good heat sink is always recommended

[@Randoz001]

Question I am new to this so, I need to make a 12v. 12000mah rechargeable battery. My old one is dead and wont hold charge. Can some point me in the right direction of how to begin this project with a video recommendation. I need tools and supplies as well. I only need 2 leads coming out of the battery to charge. Thanks

[@hamzahafeez1505]

Did you find any help? I also want to make my own battery for various projects. How should I go about it?

[@rickdoggr]

What setting did you use on the spot welder, mine looks like the same one but has 6 settings...

[@Chilllybob]

Which one do you have?

[@michaelkress3907]

Thank you appreciate the information DIY circuit boards convene all in one approach to that that’s really good thanks And I like the strip used for connecting those in the series parallel very nice.. I missed how many amps charge you’re battery balancer is limited to as well as how much the battery balancer is limit to on continuous output I know you can charge those batteries quite hard as well as you can discharge him rather hard also easily pulling out more than 20 A and easy to charge them at close to 10 A Each

[@Markymark.W]

I'm looking at making the same battery but I can't find any info on how to charge them. What sort of charger would I need to charge a DIY 18650 battery ? Thanks Mark

[@tjmethod8623]

Hey do you make custom battery packs? I'm looking to have 2- 4 cell 14.4 packs running in parallel for 12 volt custom made heated gloves. If not can you recommend someone? I could do it myself but I'm not exactly sure what I need. Thanks

[@mochariefazzmisantoso2508]

can you give us the link to buy your spot welder? great video btw!

[@bytesizedengineering]

Thanks! I just pinned a comment with a link to a spot welder that is similar to mine.

[@AbelMata-ng4bl]

Hi, how many 3.7 cells18650 I need to build a 12v 100am or 24v 100ah? thank you

[@kevinemery1177]

Got my subscription

[@Chilllybob]

What exact welder are you using in this video.Thank you in advance.Also what nickle strips do you recommend for small projects like 8 AA battery packs

[@didikpurwianto9104]

Thengk you ser...

[@L457_W15Hexe]

What is name of the device that you used for welding the nickel strips

[@ecocentrichomestead6783]

I was wondering if I could use craft foam. Because I have a bunch of it. Thanks.

[@Kroppyboi2]

I love the little details to your editing. The spot welds going on best specifically. Nice touch

[@khalilkh7389]

Wich spot welder Are u using? the link is not showing Thanks 😃

[@herbboughner3944]

Enjoyed your video,? If I build a pack like you did 48 v and 10 amp could I plug it into my 48 v 10 amp battery on the charging port to obtain the same voltage but longer use with the extra amps.

[@Nitecrow314]

No, you can not safely connect two batteries through the charging port. The wires are way too small, and you would be feeding current the wrong way through the BMS.

[@golubevden]

@bytesizedengineering I have a dilemma, would you charge and balance the cells before making a battery pack and welding them?

[@bytesizedengineering]

@@golubevden if you are recycling batteries from various sources, it's extremely important to make sure they are matched with other cells that have the same internal series resistance. Cells that are in parallel need to have the same capacity. I purchased my cells brand new

[@golubevden]

@@bytesizedengineering the cells I have for my project are brand new. I bought them a couple of months ago

[@medeostudios]

Very Interesting thanks

[@tombouie]

Thks & question; I have multiple USB battery packs. ??How would I combine them serially?? ??Is there a hub I can get to combine them??

[@atikabul5895]

hello dear sir frist thanks for this education video my question is , can we using three of this kind battery parallel together without BMS extra between them ?

[@JonathanRansom]

I'd be so scared working on that the whole time. You made it look easy though!

[@bytesizedengineering]

I was scared until I got the insulation put on. I may have shorted some solder wire and vaporized it in a spectacular fashion. That didn't make it into the video...

[@JonathanRansom]

@@bytesizedengineering sounds like a Patreon clip! Haha I'd like to see that.

[@pbat118]

Can u ful the tubular frame with the batterries to add extra power or switch over an even have a dynamo built in like an alternative to recharge them when using the alternative hidden batterries

[@downlink00]

Id like to build a bunch of these little batteries to fit in the trunk (tire well) to power a car audio system. I need 12volt, up to 500 continous amps and as many amp hours as i can fit. Do you know of any reason this wouldnt work?

[@sentient1640]

Can you upload a circuit diagram for the battery pack you have made? I didn't understand the connection among the batteries. Thanks.

[@2004rami]

Tops job's 🌠🌠🌠🌠🌠👌🔝

[@jboy6944]

Hi, I’m an electronics engineer, and I’ve been meaning to build a battery pack. My only concern is sourcing the batteries. Most markets sell at an extremely high price. Do you know any manufactures that source at a reasonable price ?

[@farzan-22]

Thank you😸

[@farzan-22]

Do you have to use a BMS board?

[@Wouterium]

Great vid! I do have one question though, maybe it's a trivial answer but, how would you go about charging these lads?

[@bytesizedengineering]

That is the whole purpose of the BMS unit. You plug the charging cable into a battery charger

[@Wouterium]

@@bytesizedengineering So the BMS regulates incoming power from the power outlet, as well as regulating the batteries' health and other stuff? I'm doing some digging into this stuff right now so your reply is much aprpeciated!

[@Calthecool]

Pretty sure you could cut those strips with the safety scissors we used in kindergarten, those massive ones look a bit overkill 🤣

[@trebor1477]

Thanks for this video. I understand now how to do 20S6P battery. I will go 6 wide and 20 in length. Samsung 50g 4850mah for my Kaabo mantis. Do you maybe have video with batteries in horizon position?

[@jodiezhao]

Hi, we are lithium batteries manufacturing, offer great batteries packs via cell matching, professional spotting and qualified assembly, ensure the best quality.

[@shantanupawar3609]

Is there any need to cycle charge them? Before assembling in on single pack?

[@mattkent655]

Your assembly and attention to details is absolutely tops. My only complaint is that there's no explanation of what you're doing and why. Someone like myself who isn't an electrical engineer and wants to do this type of project needs to understand what we're doing and why so I do it properly (and don't hurt myself)

[@mattkent655]

@@HelloDonkey9 then maybe you do a video showing the right way?

[@jarrettgilliam3159]

Question, why do you have two sets of wires on the battery pack. One connected to yellow cap and the other to the red cap

[@Aussiehomestead1965]

Output cable and charging or input cable.

[@schmeglyomigy6174]

Hi, I am a highschool student and for a fun project I decided to build an electric pit bike, as well as building a custom battery to fit the spacing required. I custom built a 52v 28.8ah (14s12p) battery with samsung cells and before I put the bms (50a 14s Daly BMS) on, I tested the pack with a voltmeter and it read around 58.6 volts, which was perfect. However, when I soldered the bms wires on, and put on the connector, it read 14.5 volts. That was around a month ago, and now when I test it the voltmeter reads around 9.5 volts. I checked all of the bms wires and they were fine, so I don’t understand how I am getting that voltage. I saw online that sometimes a BMS can be “asleep” and that you can wake it up by charging, so I tried that and it didn’t even charge. I am now feeling very frustrated and defeated, because everything went so well until the BMS part. Everything in terms of the nickel strips and batteries is good, but it is just something with the BMS. I wasn’t able to get a very good solder on the main positive wire, so that could be the issue. This is all for an electric pit bike project that I’m doing, and I just feel very defeated now, which is why I’m seeking external help. Sorry for the very long email, but this is just the problem that I am facing. Do you know a possible fix or any way I can contact you for you to provide further help. Thanks in advance.

[@Sam-tg4ii]

How bad is it to connect the batteries with ordinary wire and soldering, or friction fitting them with springs?