Sillyputty
Solar Enthusiast
- Joined
- Jul 21, 2020
- Messages
- 188
This is the timeline I recorded when top balance my EVE 280AH cells I purchased from @Amy Wan (Luyuan) at Shenzhen Luyuan.
Tools:
I hope this helps someone else that’s freaking out during parallel balancing of their EVE cells.
Tools:
- Cheap 10A - 30V Power Supply (w/new 10 gauge leads and larger clips)
- Two tested multimeters - to confirm accuracy
- Patience
- Paralleled cells and set PS to 10A and 3.65V
- 6/9/21 - All cells at 3.26V
- Charged for 9 hrs - Cells now at 3.29V - Turned off charger
- 6/10/21 - Cells at 3.29V
- Charged for 15 hours - Cells now at 3.31V - Turned off charger
- 6/13/21 - Cells at 3.3V
- Charged for 4 hours - Cells now at 3.33V - Turned off charger
- 6/14/21 - Cells at 3.315V
- Charged for 17 hours - Cells now at 3.336V - Turned off charger
- 6/15/21 - Cells at 3.330V (?)
- Charged for 14 hours - Cells now at 3.349V - Turned off charger
- 6/16/21 - Cells at 3.300V (??) What the hell.
- Charged for 15 hours - Cells now at 3.35V - Turned off charger
- Re-calibrated/reset power supply and moved clips to busbars
- 6/17/21 - Cells at 3.33V at 9AM
- Amps began dropping at power supply at 2PM
- PS switched from constant current to constant voltage at 2:30PM
- Voltage at battery w/power supply on = 3.44V
- Voltage began rising ~ 1mv every 10 seconds
- Amps decreased to 4.5A after 30 minutes
- Voltage at PS and batteries reached 3.63V at 4PM
- Voltage at PS and batteries reached 3.649 at 5PM
- Amps at PS = 0.66A
- DONE after 82 hours
- 6/18/21 - All cells at 3.545V after resting 16 hours.
- Approximate time at constant current (CC) of 10A: 79 hours
- Approximate time at constant voltage (CV): 3 hours
- Going from ~90% charged to ~100% is FAST!
- Despite power supply showing 3.74V under load while charging, repeated tests under no load showed it at 3.65V
- Both meters were used and watched carefully during CV phase - one on batteries and one on PS output. Neither reached more than 3.65V
I hope this helps someone else that’s freaking out during parallel balancing of their EVE cells.