Battery Pack

Projects General Guidance
1

Hi all, I have a few of Lithium Ion battery 3.7v 18650 900mAh. I plan to connect it in parallel (1S4P) and place a BMS on the battery pack.

I have enquiries;

  1. Will one piece of 1S BMS enough for this configuration? My usb charger is about 1A. Or I need multiple BMS?
  2. How will I know the battery has built in PCB?

Thank you.

2

By PCB, I assume you mean protection circuit. Having a capacity of only 900mA rather suggests it is protected, but the best way to check this is by reading the writing on the battery.