I need to build a 10 kWh lithium-ion pack, anywhere from 70 V to 200 V. This is to drive a motor. Power output will not exceed 15 kW. The cells will be Panasonic NCR 'B' at 3.4 Ah 18650. I would like to minimize space and weight and cost. :D Level of safety would be standard for a hobby application. Charging will be done in a safe area using two levels of overcharge and overcurrent protection. Charging is from house current, 110V, and multiple chargers may be employed to double or triple the charge rate.
- What is the best configuration for cells? I would prefer if the pack is broken down into units of 1 to 2 kWh each. Each unit may be charged separately.
- In addition to a balancing-protection board and a CCCV charger, what other protection or safety mechanisms are recommended, short of a smart BMS system?
- I have looked at a cheap Chinese balancing board that offers protection (thermal, overcharge, undercharge, overcurrent, short). A 20S board will offer up to 84 V and adequate current for the application, for a 1.5 kWh unit. At 1/3C, I would need a 83 V 6 A CCCV charger. How do I get one of these?
- Off-topic question: Can a balancing-protection board be used for a configuration with a lesser number of cells? Such as using a 10S board to control an 8S configuration. Or does this depend on the board?