fivari
10 W
I recently bought this battery pack on ebay. The building quality is fine, the BMS is solid.
Specs: 48V40Ah (16s13p) BMS 60A
HOWEVER, after one month there are a few concerns:
What might be the other possibilities and what is the solution?
Thanks!
Edit: I add the information about the cells that were used to build the pack, according to the Chinese vendor.
> Battery Material LiFePO4, Model CDP-26650ID
> Nominal Voltage (V) 3.3V
> Nominal Capacity
> (Ah) 3100mAh
> Internal Resistance (mOhm) <15
> Life Cycles >1500
> Maximum Charge Voltage 3.65V
> Cut-off Discharge Voltage 2.0V
> 10 sec pulse discharge 5A
> Continuous Discharge Current 3.1A
Specs: 48V40Ah (16s13p) BMS 60A
HOWEVER, after one month there are a few concerns:
- when I ride full throttle, the voltage sags from 53,8V down to 49V. The current drawn at that moment is 40A.
- fully charged the voltage is 58.5V, but a few hours later the voltage has dropped down to 53,8V
- I did a capacity test at 10A using a resistor and after 34 Ah the BMS cuts out the battery. The overall voltage at that moment was still 48V, so probably one string was at LV
What might be the other possibilities and what is the solution?
Thanks!
Edit: I add the information about the cells that were used to build the pack, according to the Chinese vendor.
> Battery Material LiFePO4, Model CDP-26650ID
> Nominal Voltage (V) 3.3V
> Nominal Capacity
> (Ah) 3100mAh
> Internal Resistance (mOhm) <15
> Life Cycles >1500
> Maximum Charge Voltage 3.65V
> Cut-off Discharge Voltage 2.0V
> 10 sec pulse discharge 5A
> Continuous Discharge Current 3.1A