sed6
Knows just enough to be dangerous...
- Joined
- Apr 17, 2020
- Messages
- 128
After some 15 months of being completely ignored my Tesla batteries gave me a big middle finger last night. Cells 1 & 2 are 3.5v and cells 4-6 are 4.0v. After discharging overnight to 21.4v Cells 1 & 2 are 3.1v and cells 4-6 are 3.8v an even bigger spread. Ugh. So I'm scrambling to figure out a solution and determine why those two cells went so far out.
Some solutions I'm considering.
a) Charging cells 1 & 2 with a hobby charger to get them up to voltage and then Installing a 5 amp 6s active balancer to keep them even.
b) Skip charging and see if the 5A balancer can bring them back to balance in a reasonable amount of time (anyone know the math on that?).
c) Consider the SimpBMS or other BMS solution. I'll only try this if #1 or #2 fails.
Some causes I'm thinking about.
a) My 6 Cell Cell Monitor I have plugged into each somehow drains cells 1 & 2?
b) I'm charging to 24.5v and discharging to 22.5v so that's about 85%-25%. Wonder if going to 100% would help?
c) These were used cells from a wrecked 70k mile car, I guess the cells could be reaching their end of life?
I'm open to questions, suggestions, solutions and I told you so's...
Thanks all!
Some solutions I'm considering.
a) Charging cells 1 & 2 with a hobby charger to get them up to voltage and then Installing a 5 amp 6s active balancer to keep them even.
b) Skip charging and see if the 5A balancer can bring them back to balance in a reasonable amount of time (anyone know the math on that?).
c) Consider the SimpBMS or other BMS solution. I'll only try this if #1 or #2 fails.
Some causes I'm thinking about.
a) My 6 Cell Cell Monitor I have plugged into each somehow drains cells 1 & 2?
b) I'm charging to 24.5v and discharging to 22.5v so that's about 85%-25%. Wonder if going to 100% would help?
c) These were used cells from a wrecked 70k mile car, I guess the cells could be reaching their end of life?
I'm open to questions, suggestions, solutions and I told you so's...
Thanks all!