SwampDonkey
100 W
- Joined
- Mar 27, 2018
- Messages
- 227
Im having a hard time getting home built ebike batteries to work due to conflicting info about BMS's. Maybe we can clear up some confusion here.
1. How do people get away with "bulk charging" large batteries? Wouldnt this lead to the battery becoming unbalanced?
2. Are the balance wires accurately colored? Some have all red (positive) with one black (negative), some are reversed.
3. Can you measure the charging voltage on the balance wires? Will they increase by 3.6-4.2V as you move from one end of the battery to another?
4. What are the benefits of "bypassing" the BMS? Will it still balance charge?
5. Why are unbalanced groups a bad thing? Isnt the whole point of the BMS to preferentially charge groups until they reach cutoff voltage? Seems like as long as the batteries in the parallel groups are close.
6. How does "one bad cell" screw up a whole pack? They're all connected, seems like it would just decrease power by 1 cell.
1. How do people get away with "bulk charging" large batteries? Wouldnt this lead to the battery becoming unbalanced?
2. Are the balance wires accurately colored? Some have all red (positive) with one black (negative), some are reversed.
3. Can you measure the charging voltage on the balance wires? Will they increase by 3.6-4.2V as you move from one end of the battery to another?
4. What are the benefits of "bypassing" the BMS? Will it still balance charge?
5. Why are unbalanced groups a bad thing? Isnt the whole point of the BMS to preferentially charge groups until they reach cutoff voltage? Seems like as long as the batteries in the parallel groups are close.
6. How does "one bad cell" screw up a whole pack? They're all connected, seems like it would just decrease power by 1 cell.