A 5S lithium-ion Battery Management System (BMS) protection board designed for compatible cordless drill and electric screwdriver battery packs. It supports a 21V full-charge battery configuration and is intended for battery packs requiring protection against abnormal charging, discharging, and current conditions. Verify the exact board's current rating before installation.

Full Description

This 5S 20A BMS protection board is designed for compatible five-series lithium-ion battery packs commonly used in cordless drills and electric screwdrivers.

The board uses power MOSFETs and battery-monitoring circuitry to manage charging and discharging and provide protective functions. Depending on the specific board version, these may include overcharge, over-discharge, overcurrent, and short-circuit protection.

A standard 5S lithium-ion pack has a nominal voltage of approximately 18V–18.5V and a full-charge voltage of 21V when using cells rated at 4.2V maximum each.

Important: The 20A rating and protection features must be confirmed against the exact board version. Follow the PCB connection labels and the manufacturer's wiring diagram. Use a compatible 21V charger designed for a 5S lithium-ion battery pack.

Technical Specifications

Product Applications

• Cordless electric drill battery packs.

• Rechargeable screwdriver battery packs.

• Compatible 5S lithium-ion battery assemblies.

• Replacement and repair of compatible power-tool battery protection boards.