Hi All.
Hoping to ask for your help with my problem. I have built a 120 AH, 12v 4s Lifepo4 diy battery for deep cycle (trolling motor) use that is about 3 years old now. Sorry not solar but I am banking you guys know how to help.
The battery has been working fine but when I put it into storage (between fishing trips or over winter) the voltages displayed on JBD/overkill/Chinese (these all appear to be the same form factor) bms app (xiaxiong 3.1.1026) voltages go crazy. By crazy I mean all cells are happy...within say .05v for days or weeks. Then all of a sudden with no load BMS goes crazy (see pictures taken minutes apart with no load applied) and the bms shuts down and will not allow charge or discharge. Probing each cell they are all within .05v at the target 3.2v storage soc as measured with a multimeter.
If I can get it to accept a charge just a second or two and the bms returns to normal showing good and consistant values. (Back to 3.2 with .05 max deviation)
Do I have a faulty BMS or is this a known issue?
Since it's a pain to get inside the battery on the water I am thinking I may put a switch on the first (red) balance lead so I can "disconnect" the bms from outside the battery. Seems a disconnection reboots the bms and good values return. I've wired in a physical on/off switch to the bms but this doesn't power down the bms, just toggles discharge function so crazy remains. Anyone had this issue? Any issues with switching the balance lead on say a momentary push button...reset switch of sorts?
Thanks for your opinions and asssitance!
Hoping to ask for your help with my problem. I have built a 120 AH, 12v 4s Lifepo4 diy battery for deep cycle (trolling motor) use that is about 3 years old now. Sorry not solar but I am banking you guys know how to help.
The battery has been working fine but when I put it into storage (between fishing trips or over winter) the voltages displayed on JBD/overkill/Chinese (these all appear to be the same form factor) bms app (xiaxiong 3.1.1026) voltages go crazy. By crazy I mean all cells are happy...within say .05v for days or weeks. Then all of a sudden with no load BMS goes crazy (see pictures taken minutes apart with no load applied) and the bms shuts down and will not allow charge or discharge. Probing each cell they are all within .05v at the target 3.2v storage soc as measured with a multimeter.
If I can get it to accept a charge just a second or two and the bms returns to normal showing good and consistant values. (Back to 3.2 with .05 max deviation)
Do I have a faulty BMS or is this a known issue?
Since it's a pain to get inside the battery on the water I am thinking I may put a switch on the first (red) balance lead so I can "disconnect" the bms from outside the battery. Seems a disconnection reboots the bms and good values return. I've wired in a physical on/off switch to the bms but this doesn't power down the bms, just toggles discharge function so crazy remains. Anyone had this issue? Any issues with switching the balance lead on say a momentary push button...reset switch of sorts?
Thanks for your opinions and asssitance!