Battery 101


4s Square 14.8V-16.8V 15A 18650 Li-Ion BMS

4s 14.8V-16.8V 15A Li-Ion Square 18650 protection board is a small PCB mounted Lithium Battery protection module. This small and smart protection module comes with various features like Short-circuits, Over-charge, Over-discharge and Over-current protection. It is straight forward to install and convenient to use in all your DIY portable projects.

Suitable for lithium-ion cells in a 16.8V (max voltage) 4s configuration.


  • Model: 4S Li-ion – 14.8V-16.8V
  • Over-Charge protection: 4.25V-4.35V
  • Over-Discharge protection: 2.5V-2.8V
  • Cont. working Current: 8A
  • Max peak current: 15A
  • Static current: less than 20uA
  • Internal Resistance: Less than 50mΩ
  • Operating Temperature: -20℃ -60℃
  • Delay self-recovery
  • Size: Approx.: 36 x 36 x 3mm

Package included: 1 x Li-ion Battery 4S 15A Protection board.



These BMS protection modules may arrive "Activated".  Apply 16.8V across the charge/load terminals will reset the board.  If after assembling your pack, you have zero volts at the PCB terminals or if you've shorted the PCB terminals, connect 16.8V to the charge/load terminal will reset the board.



This BMS will require a competent and knowledgeable person with an electronic background and skills to install and operate. As these are sensitive products, we will only accept returns if its un-opened and un-used. 

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