|
I would keep them. You want to have power to the car while you're charging the small pack.
I think I have an inexpensive option for charging a 4S pack at a reasonable rate to whatever voltage you want. Grab yourself a 12V power supply, and four adjustable dc-dc buck converters. Set those to 3.9 or whatever voltage you want. Like an RC balance charger you don't need an onboard BMS then. The 12v power supply and dc-dc converters can be had for less than $30. The ones I found will charge at 5A which is the same as my current lead acid charger and it is large enough for my use.
|