5S BMS 21V 20A Li-Ion Battery Protection Board for Power Tools
5S BMS 21V 20A Li-Ion Battery Protection Board for Power Tools
5S BMS 21V 20A Li-Ion Battery Management Protection Board for Electric Drills & Power Tools
Keep your 5-series lithium-ion battery packs running safely and efficiently with this compact, high-quality 5S BMS (Battery Management System) Protection Board. Designed specifically for 21V electric drills and cordless power tools, this PCBA board monitors each cell in real time and provides robust multi-layer protection to extend battery life and ensure safe operation every time.
Made in Mainland China.
Key Features
- 5S Li-Ion Compatible: Designed for 5-series lithium-ion battery packs rated at 3.7V per cell (21V total charge voltage).
- Real-Time Cell Monitoring: Uses a dedicated 5S lithium IC processor to continuously detect voltage, charge/discharge current, and ambient temperature across all cells.
- Multi-Layer Protection: Built-in safeguards include overcharge protection, over-discharge protection, and short-circuit protection for reliable and safe operation.
- Continuous Discharge Current: Handles 8–20A continuous discharge, making it suitable for demanding power tool applications.
- Ultra-Low Power Consumption: Working current of approximately 25µA and quiescent current of approximately 6µA — minimal self-drain when idle.
- Dual MOSFET (2 MOS) Design: Enhanced switching performance for more efficient charge and discharge cycles.
- Compact Form Factor: Measures just 58 × 63 mm — easy to integrate into most battery pack housings.
Technical Specifications
- Configuration: 5S (5 cells in series)
- Charge Voltage: 21V
- Single Cell Charge Voltage: 4.25V
- Overcharge Detection Voltage (per cell): 4.25V
- Continuous Discharge Current: 8–20A
- Working Current: ~25µA
- Quiescent Current: ~6µA
- MOSFET Count: 2 MOS
- Board Size: 58 × 63 mm
- Model Number: 5S21V-2MOS
Package Contents
- 1 × 5S BMS 21V 20A Li-Ion Battery Protection Board (PCBA)
Note: Battery cells, charger, and power tool are NOT included. Due to manual measurement, please allow a tolerance of 1–3 mm. Actual product color may vary slightly from images due to different monitor display settings.
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Frequently Asked Questions
Q: What type of batteries is this 5S BMS protection board compatible with?
A: This BMS protection board is designed for 5-series (5S) lithium-ion (Li-Ion) battery packs with a nominal cell voltage of 3.7V per cell, resulting in a total charge voltage of 21V. It is ideal for use in cordless electric drills and other handheld power tools.
Q: Does this board include overcharge and over-discharge protection?
A: Yes. The board features built-in overcharge protection, over-discharge protection, and short-circuit protection. The overcharge detection voltage per cell is set at 4.25V, helping to safeguard your battery cells and extend overall pack longevity.
Q: What is the maximum continuous discharge current supported?
A: This BMS board supports a continuous discharge current of 8–20A, making it well-suited for the demanding load requirements of electric drills and similar power tools.
Q: Are batteries or a charger included with this BMS board?
A: No — this listing includes only the BMS protection board (PCBA). Battery cells and charger must be sourced separately and are not included in the package.