Help, battery pack needs repair

hello guys, need some help with my battery i have cut off 2 rows each 6 batterys, they were 0,2 V and 0 V and want to replace them, they look good but they dont want to hold the charge. But the problem is that i have 2 batterys that look like they contacted somehow and burned a bit, should i change them or not ? it’s not soo eazy to get them savely off and it would be a pain to weld them back especially coz ill be using someonce stationary pointwelder or however its called. IMG_20190207_130235 IMG_20190207_130246

if you are wondering what the black thing is- its iso-tape (i hope that its called like this in english XD)

1 Like

In English we just call that electrical tape.

Was it taped up before, or did you recently add it since it looked like there was a short? I bet you that it was a result of something I’ve commented in the past:

You should always isolate between P groups else you risk the insulation wearing away.

I believe that the cell on the left is probably okay because it didn’t have current flowing through it when it burnt out, but it is likely damaged.

The P group on the right should be binned. I would replace it, however, that’s just my opinion.

If you want to check if it’s damaged, repair the rest of the pack, get it balanced and fully charged, and then discharge to ~50% without a BMS. If the P groups have considerably drifted from each other, replace the ones that have gone bad.

voltage looks good on all cells that are still there, if its a bad cell what could happen ? i really dont want to take them apart later, it’s not so easy for me to get to the person with the welder. and yes the tape wasnt there at first

oh and its not glue but something like rubber, it didnt damaged the casing, at least not where i took it apart, it comes off pretty easy

Those edges are so damn sharp

Who have build that pack for you? :hushed:

someone who is working at a mbs store and making their electification

Hmmm, I think the package does not look so good. I see that you had the place to use plastic spacers, the sharp edges are not cut from the nickel, in some places it looks like the welds are not perfect & I wonder where the heatshrink is.

This is a pack that I built two days ago and now has to prove itself in a tramp of a customer. Where do you live? maybe some battery guys on the forum can help you :slight_smile:

2 1

wow looks crazy, but the big problem is that i am in Novosibirsk (Russia) xD and its -28 celcius and the pack was on the cheaper side so no wonder that just has what it needs and not more

привет! никогда не экономьте на батарее :stuck_out_tongue_winking_eye:

1 Like