Christobel931
100 mW
I have a 36V 15ah Lifepo4 pack that seems to be out of balance. The LVC is ~30V however, It cuts out at right on 35v under a load of ~21amps.
Measuring the battery after use I find the cells pretty evenly drained to ~3.3v resting, except for one that is only 3.07v.
During charging this cell comes up, but slower than the others and some others peak at ~3.8v. Then the green LED on the charger comes on and output is shown to be 44.8v at the battery connection. If I measure the voltage at the last BMS wire coming out of the pack, its 41V.
If I unplug the charger, it drops to ~40.6v at the battery connection. I can leave it on for 15 hours, same thing.
As I understand it, the BMS should shunt current away from the "high" cells to top off the others, correct? Shouldn't the "higher" cells LED's come on as current is shunted to lower cells. I haven't seen any LEDs come on at all and the BMS does not get warm at all during charging. I have tried two chargers, both put out just over 44v.
I have read through some of the other battery tech threads, and from what I can tell, the BMS is not doing it should, or the charger is getting a "false" reading?
Any ideas what is going on with this?
Measuring the battery after use I find the cells pretty evenly drained to ~3.3v resting, except for one that is only 3.07v.
During charging this cell comes up, but slower than the others and some others peak at ~3.8v. Then the green LED on the charger comes on and output is shown to be 44.8v at the battery connection. If I measure the voltage at the last BMS wire coming out of the pack, its 41V.
If I unplug the charger, it drops to ~40.6v at the battery connection. I can leave it on for 15 hours, same thing.
As I understand it, the BMS should shunt current away from the "high" cells to top off the others, correct? Shouldn't the "higher" cells LED's come on as current is shunted to lower cells. I haven't seen any LEDs come on at all and the BMS does not get warm at all during charging. I have tried two chargers, both put out just over 44v.
I have read through some of the other battery tech threads, and from what I can tell, the BMS is not doing it should, or the charger is getting a "false" reading?
Any ideas what is going on with this?