Faster charging for Enginer kit

Hello hk,
The BMS was rated at 25a. I had one customer that had this part of the BMS fail and it took out some cells with it. The risk is that if the BMS fails to disconnect the charger you will damage the battery pack. In this case, the BMS failure happened just from the startup spike that the chargers give at turn on. So you need to have the BMS rated much higher than the charge current.

I have done some work on charging at faster rates. There are 2 other potential problems.

One is that at 110v the input for a 30A charger will be a little above 20a with a higher turn-on spike. This requires a 30a CB in your fuse box and 10AWG wire.

The second is that you will see cells climb in voltage at higher C rates well before they are fully charged. Fast charging works for lower SOC but you need to slow down the charging rates when the SOC gets up to about 3/4 full. That is why all the fast chargers are spec'd for partial charges.

Thanks,
Dan

 

speaking of which, I have read in other parts, that it is good practice to decrease the current towards the end of a charge , is there a such adjustment on the stock charges?