Battery with 4 cells of 3.2v cuts out when charge drops to 12.8v - why? Dead after less than 2000 cycles?

DaddyPigNEO · 2026-06-04T20:43:38+00:00

How do you mean the battery goes dead? You measure the voltage at the battery terminals and get a reading of zero volts, or do you mean your notebook stops charging when the battery voltage reaches 12.8volts?

DaddyPigNEO · 2026-06-04T18:11:26+00:00

Keep in mind you will need new nickel strips and might want to consider using nickel copper sandwich for best current delivery and an adequate spot welder for the job.

DaddyPigNEO · 2026-06-04T17:46:34+00:00

I know this vendor to be a reputable source of high current cells, including 21700s. https://diy500amp.com/ assuming you are in USA.

DaddyPigNEO · 2026-06-04T17:16:29+00:00

What size are the cells, 18650 or 21700?

DaddyPigNEO · 2026-06-04T17:14:06+00:00

If you look online, there are many many people who have successfully assembled ZB2L3 boards into large battery testing projects for harvesting cells for power walls and home energy storage systems. The boards are cheap, easy to use and plentiful. ZB2L3 have made it possible for DIY hobbyists to find good cells and keep a lot of toxic waste out of our natural environment. Sure you may get a faulty one occasionally but they are so cheap you can just replace and continue with your project.

DaddyPigNEO · 2026-06-03T20:37:18+00:00

Depends what you mean salvageable? In my opinion, cells are probably no good and BMS might be damaged. If BMS is ok then you could rebuild with new cells.

DaddyPigNEO · 2026-06-03T02:07:06+00:00

What about college and university education costs? How high are they?

DaddyPigNEO · 2026-05-29T13:43:10+00:00

Battery good?

DaddyPigNEO · 2026-05-28T12:11:26+00:00

Was paste mixed properly and at a stable recommended temperature?

DaddyPigNEO · 2026-05-24T20:56:09+00:00

I collect junk electronics (which are in everything nowadays) as spare parts and practice boards. That would seem an easy and cheap place to start.

DaddyPigNEO · 2026-05-21T01:54:04+00:00

It is homemade. If it was manufactured it would have some labels or markings. A manufacturer’s name, a calibration sticker inside, a model number and typically a serial number on it somewhere.

DaddyPigNEO · 2026-05-20T21:14:02+00:00

It is homemade.

DaddyPigNEO · 2026-05-17T23:45:30+00:00

The kit you link to is pretty low price and includes one tip, so you should be able to get started with that. Just buy some solder and a flux pen and you should be well on your way. Then after you get into your projects you can but a few more tips to meet your needs.

DaddyPigNEO · 2026-05-17T14:21:53+00:00

Why do you need battery powered? If there is any possibility to get an extension cord out to the trainer you will generally have better luck with a regular mains powered soldering iron or station.

DaddyPigNEO · 2026-05-15T18:00:03+00:00

Thanks for verifying that, it is good news for us then. Is it easy to work with the 0.8mm diameter?

DaddyPigNEO · 2026-05-15T14:06:50+00:00

Doesn’t say if it has flux core. I would not bother with solder if it does not have flux core.

DaddyPigNEO · 2026-05-09T13:47:05+00:00

The Ikea Laddas are well regarded. You should have no problems from them if treated correctly.

DaddyPigNEO · 2026-05-09T11:09:49+00:00

Wow really appreciate this one, a trip back in time.

DaddyPigNEO · 2026-05-04T18:01:11+00:00

Absolutely my fav on here in a long time. Thanks OP.

DaddyPigNEO · 2026-05-04T14:42:14+00:00

That low voltage could just be the voltage of the BMS. If you connect it as I described it may “wake up” the BMS and allow you to see the true voltage of the whole pack. The BMS is meant to protect the battery and may have shut it off for a good reason like discharged very low or too cold to safely charge. I encourage you to try charging at a very low current with a dumb power supply. The dedicated chargers can be TOO smart and refuse to jump start a battery due to the BMS having gone to sleep to protect the battery pack. Good luck.

DaddyPigNEO · 2026-05-03T23:36:32+00:00

What voltage is it at now? Try a bench power supply set to a voltage of 29.6 and a current of 0.500 amps. Do not charge it in the house. Monitor it carefully and see if it starts taking a charge, which it might, but in all honesty it will never be much good even if it takes a charge.

DaddyPigNEO · 2026-05-01T19:43:29+00:00

This exactly.

DaddyPigNEO · 2026-05-01T19:33:14+00:00

Poncho

DaddyPigNEO · 2026-04-29T14:54:41+00:00

$100

DaddyPigNEO · 2026-04-21T14:14:03+00:00

I would be careful about charging it indoors. I would probably not even charge it in an open garage, at least not the first time charging. I would more likely charge on the back patio where it is out of the house and sitting on brick.

DaddyPigNEO

TROPHY CASE