my Wattcycle experience

[blenderbender]

I received (8) 12.8v 100ah batteries recently from Wattcycle and one was DOA. After a couple email exchanges that included pics of multi meter readings and answering a couple questions they sent me out a new battery with no need to return bad battery. Of course I'd have preferred to get (8) good batteries the first time around, but I can't complain about their speedy response and follow-up. I'm not certain what I might be able to do with the bad one. Must be a BMS issue maybe as it shows zero volts when I hook up a LiFePo4 charger and I can't get it kick started. I don't know enough about these batteries so any input is appreciated.

 

[Rexracer]

I had a similar, zero volts issue with an inexpensive 12ah lifepo4 battery from Amazon. Vendor replaced and let me keep the battery. I cut it open and found a broken solder connection. I re-soldered it, taped the case together, and it's been working perfectly since.

I would (carefully) open it up and look for a loose or broken connection. Repair it and You could easily end up with a really nice, free backup battery!

 

[robbob2112]

Pop the top as was suggested.

For asstetics I would use a jewelers screwdriver to open the middle along the front side. Then very carefully heat right around the lid and either use the jewelers screwdriver or a metal putty knife to work your way around.

Their glue is a pure silicone adhesive so it softens when it warms up. You want to be careful not to heat the old case, just where the lip and glue is. And you do not want to get the whole battery hot.

If you don't want to take yer time and be delicate the oscillating tool works fine and when the seam is covered in electrical tape it barely shows.

If it is more than a loose connection and new basic 4s BMS is about $40 to $50... one with all the bells and whistles is around $120....

 

[blenderbender]

Thanks, I’ll give it a go at some point.