sheepslinky
New Member
- Joined
- Feb 25, 2021
- Messages
- 2
I have 2 100AH renogy lifepo4 batteries -- the older generation, not "smart". The temperature dropped, the batteries went below 0 degrees C, and it's likely the charge controller did not cut off the charge when the temp went below 0C. I don't know the behavior for LiFePO4 batteries when they fail, so I could use some help confirming my belief that they are completely toasted. When I called renogy, nobody could answer whether or not the BMS even protects from low temps. I somehow had assumed that "temperature protection" included cold protection, but I now see that only a high temp cutoff is noted in the manuals.
I put them on the bench, tried to charge them individually with a renogy dc-dc charger. Here's what I found:
The batteries will still discharge, but will not take a charge. I didn't put a heavy load on them, but they will power 10-30W of LED lighting.
The resting voltage on the batteries is 12.6V. When the charger is connected, it sets the charge voltage at 13.5V. However, the current is only a few milliamps (nothing really).
Am I right to assume that the BMS does not protect in cold temps? Is this the expected behavior of batteries when charged at low temps? Is there anything I can salvage from these batteries?
Thanks
I put them on the bench, tried to charge them individually with a renogy dc-dc charger. Here's what I found:
The batteries will still discharge, but will not take a charge. I didn't put a heavy load on them, but they will power 10-30W of LED lighting.
The resting voltage on the batteries is 12.6V. When the charger is connected, it sets the charge voltage at 13.5V. However, the current is only a few milliamps (nothing really).
Am I right to assume that the BMS does not protect in cold temps? Is this the expected behavior of batteries when charged at low temps? Is there anything I can salvage from these batteries?
Thanks