Build’s fucked. I have no fucking clue what happened, btu the battery was acting weird from the start. brand new pack. Already out of balance when I built it (one group was 90mV down)
Full charge it was still a 90mV delta.
two cycles later the difference is at a whopping 200mV.
Top balance that one questionable group
Hook it up to the bathtub water heater drain tester 9000000000000000 (like a 2.5A load)
All groups held perfectly tight and balanced all the way to 3.6v. When I checked on it again at 3.4v, the BMS had cut discharge already, bad group was down below 3V, rest were at 3.4. WHAT THE FUCK MAN
I cant even afford to build a new pack right now. I have plans for this summer that take priority, this entire build was done because I had ALL of the electronics already lying around.
Nothing is mechanically wrong with the pack. I removed the BMS, desoldered the main battery leads, will fully wrap the pack with a whole lotta fishpaper and take it to recycling. fuck me man
Just had an idea- could you cut the nickel on the troublesome p-group, then run a bypass wire around?
You’d have the dead weight of the dead p-group, but at least you don’t have to toss the pack
Edit: if you wanted to be extra jank, you could drain the dead p-group down to 0v, then just solder the bypass wire across the terminals (shorting the dead p-group). you wouldn’t even need to cut nickel.
Using sharp flush cutters is crucial for this, but it allows you to break large nickel connections without having to tear up spot welds. Nickel is sheet metal after all. It acts like sheet metal, and can easily be torn.
For anyone reading this who is not Evan: DO NOT TRY THIS. IT’S WAY TOO EASY TO FUCK UP AND SHORT A CELL.
i would never say something that pretentious unironically
