Cold killed my 12V LiFeYPo
- Thread starter koter
- Start date
wesnewell
100 GW
Sure it will. You just have to program it properly.
dogman dan
1 PW
It's a shame you may have to cut the top off that thing. But I see no other way to be certain you get even half assed balanced after such a deep discharge. A shame it has no balance plug at all.
On the other hand, if it seems to behave normally after a charge to 13v, maybe it's good enough balanced to leave it be. See if it seems to hold a charge at 13v. If it does, then you are less likely to have one cell overcharged I think. If you have a cell at 4v when charged to 13v, it should lose it's charge fast. Then when back on the charger, if it regains that voltage crazy fast, that would also tend to confirm that one cell is full. Or maybe that one cell is just bad. If all cells are at 3.25 and more or less ok, then you should see little drop overnight. Most even slightly damaged lifepo4 won't self discharge much past 3.4v per cell.
If it acts pretty normal, then try 13.5v, and see how it acts there. If you charge to 14v, then it only holds 13.5v, that's pretty normal for lifepo4 with some wear on it.
I wouldn't make any judgments though, till the battery is warmed up.
On the other hand, if it seems to behave normally after a charge to 13v, maybe it's good enough balanced to leave it be. See if it seems to hold a charge at 13v. If it does, then you are less likely to have one cell overcharged I think. If you have a cell at 4v when charged to 13v, it should lose it's charge fast. Then when back on the charger, if it regains that voltage crazy fast, that would also tend to confirm that one cell is full. Or maybe that one cell is just bad. If all cells are at 3.25 and more or less ok, then you should see little drop overnight. Most even slightly damaged lifepo4 won't self discharge much past 3.4v per cell.
If it acts pretty normal, then try 13.5v, and see how it acts there. If you charge to 14v, then it only holds 13.5v, that's pretty normal for lifepo4 with some wear on it.
I wouldn't make any judgments though, till the battery is warmed up.
Matt Gruber
1 MW
why cut the top off to check? drill some holes using a drill stop so it won't go in too far. stick in a probe to touch terminal and read v.
icecube57
10 MW
Normally you can bump charge it in nicad mode until its at a voltage that it can accept a charge from a regular charger. That is if you have an rc charger to use.
Yes, I did charge up 8V using 2S setting, and then 3S setting up to 10V. However I need to do a full charge to see if any cells are dead according to dogmans suggestion above, so I'm currently looking for a suitable charger that I can use LiFePo-cells, RC-packs and my e-bike project.
Drilling holes instead of cutting of the complete top was also a great suggestion btw.
Drilling holes instead of cutting of the complete top was also a great suggestion btw.
wesnewell
100 GW
Just use a regular 12V battery charger. Charge at the lowest amp setting. 12V auto chargers limit voltage to ~14.5V, That's the recommended charge voltage for you battery. And it's also the output of 99.9% of automobile/boat/motorcycle 12V systems. Hook it to your car and charge it.
I did connect the battery to a regular 12V lead acid battery charger, and it did charge the battery up to 13V.
After that I connected it to my regular solar panel setup in the boat. It seems like it's stuck at 13.1V though, so I guess some cell(s) is/are damaged. I haven't drilled a hole yet to make individual measurements though.
After that I connected it to my regular solar panel setup in the boat. It seems like it's stuck at 13.1V though, so I guess some cell(s) is/are damaged. I haven't drilled a hole yet to make individual measurements though.
wesnewell
100 GW
What's the output of your solar charger? It's going to take a long time for a small solar charger to charge up a 90ah battery.
