36V Li-ion battery pack & 12V electric system for ebike

Building a 36V 18650 lithium-ion NCA cells battery pack and a 12V electric system for headlight and other 12V electric devices. Key-switched powerlock with two positions switch on the battery pack on first position, and switch on the 12V electric system on second position. 12W Headlight and 2A USB port devices are included to the system. All components are installed into an aluminium ebike frame box. Battery pack: - 10 serial, 4 paralleled 2900mAh 3C max Panasonic 18650 NCA Lithium-ion cells. - Spot