Did i fry my battery?

Ok will do. Definately seems like the problem for sure. Also it did sit for month waiting for my new bike. Also after riding it, then charging a couple times I have noticed improvements, however something I'd still not right and it gives up early, and then works again..
 
Ok will do. Here is the bike ( I might change up its look to be more like a future bicycle rather than a vintage motorcycle though. For less looks, especially cops)










picture upload[/img]
 
Put on the charger for three days. Try for short distance and keep on chcharge for longer if better. Ir worst. Get back to us. Balance. Balance. Give it a chance.
 
Hrmm..I left it on the charger for a good while. At least a day. It went of on off on, etc and stayed on after only about 10mins of going on and off. I rode yesterday for about 25km (in the snow) and parked it overnight (outside) and today I turned it on it read 52V and on my way back home (about 10km) it kept dipping into 40V even low as 38V (I lowered the LVC value) and then cutting out. Then the voltage goes back up to 51V or 50V, but continues to do this all the way home. Sometimes it would cut out without the voltage readout even dropping, but the meter would show empty until I waited a minute. I've never seen the meter show anything less than full voltage other than when it's temporarily dead also. Does this sound like bad batteries in my pack?
Thanks again
 
still could be one pack reading low could take 3 days to balance. So you got 25km first day no cut out? It sat overnight (no charging) and cut out a lot? Time vs Time would be faster to tear BMS apart and test each pack before and after charge cycle. The way a BMS balances a pack it charges them all evenly till topped up then if one or two packs are low it discharges the good packs at a very slow rate as in fractions of an amp. Then does charge cycle again till full and discharges again if needed. from the sound of your charge cycle it did need to balance so charge for as long as possible. I also a few times first of the season would take a ride just around the block then charge 2 hours ride around the block and charge for 2 hours, this 5-6 times over a weekend would nicely balance pack for the season start.
 
After riding charging riding again etc etc i have noticed slow improvements. I could have just been dreading something i didnt want ..or something.,ill see how it goes but last night ripping through slush and snow and ice for 2hrs i was impressed. (Just not with the weather or the wetness of myself and my clothing lol)
 
Ugh. It still dies early. If I start with it reading 52V I can expect it to take me an unexpected distance/die soon. If I take it out when it reads 50V it starts shutting off on me a couple blocks from home. :( Basically there's still a 10V drop as soon as I open the throttle which cuts my ride pretty short. Looks like I'll have to rip this thing apart
 
Damn, this could be the case. Not sure exactly but I know I havent been putting it back on the charge everytime, but I will.
Thanks for all the help seems like some of you guys have all the answers and know a fair bit. Still learning about how a bms works but starting to get it all understood. Building this bike has certainly taught me a few things about electronics.
(Like before this I overlooked the importance of properly rated connectors switches and wire guage, ive also realized that if something can fall apart it will fall apart..currently rewiring the whole thing with all wires terminated and connected with ring connectors and nuts/bolts, soldering them, then hot glueing and wrapping in electrical tape. Now as im writing this i realize the electrical tape will eventually start peeling off hmm)
 
Before the winter I put every cell of my 20s LiFePO4 pack in storage mode by pulling power down to 3.2V.
A couple of days ago I wanted to revive the pack and started a bulk charge monitoring every single cell voltage every roughly half an hour. It all went well for 2 hours with all cells pretty much at same voltage, but next sample I had two cells jumped at amazing voltage of 4.85V. Obviously I stopped charging at once and started to discharge until I brought them to a safe 3.5V.
The good thing is that there was no explosion nor firework which means cells are pretty resilient to overcharge!
The bad thing is that i possibly fried those two cells.
But how is possible that in just 30 mins there was such huge voltage leap?
For clarity my cells are 50ah LifePO4 and I was charging at 5A.

Thanks!
 
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