The 6S Series 21.6V / 24.0V Lithium-Ion Battery Protection PCB with Balance Function is a high-performance BMS (Battery Management System) designed to protect 6-cell (6S) lithium-ion battery packs from overcharge, over-discharge, and overcurrent conditions. With a balance function and robust protection circuitry, this board is engineered for a wide range of applications including power tools, e-bikes, solar energy storage, and portable power systems where reliable battery safety is essential.
At the heart of the board is a BMS protection circuit that continuously monitors the voltage of each cell and the total pack current, disconnecting the load or charger if any parameter exceeds safe limits. This protects both the battery pack and your connected devices from damage, extending battery lifespan and ensuring safe operation.
The board provides three critical protection functions:
-
Overcharge protection — Disconnects the charger when any cell voltage reaches approximately 4.25V to 4.3V, preventing damage from excessive charging.
-
Over-discharge protection — Disconnects the load when any cell voltage drops to approximately 2.5V to 3.0V, preventing deep discharge that can permanently damage the battery.
-
Overcurrent protection — Disconnects the output when current exceeds safe limits, protecting against short circuits and excessive loads.
The 6S configuration means the board manages six cells in series, balancing the voltage across all six cells to ensure they charge and discharge evenly. This cell balancing function is critical for maintaining pack health and maximizing lifespan. Without proper balancing, one cell can become overcharged or over-discharged, leading to premature failure or safety hazards.
The 6S configuration provides a nominal voltage of 21.6V and a full charge voltage of 24.0V (or 25.2V depending on the specific cell chemistry), making it suitable for a wide range of applications that require higher voltage than 5S packs. This voltage range is ideal for power tools, e-bikes, solar storage systems, and high-power LED lighting.
The board features a solder pad design that supports both direct soldering and spot welding. The exposed pads allow you to solder wires directly to the board, while also being compatible with spot-welded nickel strips for professional battery pack assembly. The board includes B+, B-, BM1 through BM5 (mid-points), P+, and P- pads for battery and output connections.
The wide application range includes:
-
Power tools — High-current protection for drills, saws, and other tools
-
E-bikes — High-power protection for electric bicycles
-
Solar energy storage — Protect 6S battery packs in solar storage systems
-
Portable power stations — High-current protection for portable power
-
LED lighting — Reliable power for high-power LED lighting systems
-
Electric scooters — Safe power for personal mobility devices
Important Note: This BMS is designed for 6S (6-cell) 21.6V/24.0V lithium battery packs. For other configurations, a different protection board or BMS should be used. Always verify the voltage and current ratings match your application before installation. Ensure all wiring and connections are rated for the maximum current your application will draw.
Whether you are building a custom 6S battery pack for a power tool, assembling an e-bike battery, or adding safety protection to a solar storage system, the 6S Series 21.6V / 24.0V Lithium-Ion Battery Protection PCB provides a reliable solution. It is suitable for individual makers, engineers, and businesses purchasing in bulk for product development or industrial applications.
Features
-
6S six-cell protection — Manages six cells in series with cell balancing
-
Balance function — Ensures even charge and discharge across all six cells
-
Comprehensive protection — Overcharge, over-discharge, and overcurrent protection
-
Wide voltage range — 21.6V nominal / 24.0V full charge
-
Solder pad design — Supports both direct soldering and spot welding
-
Compact PCB design — Sized for space-constrained battery packs
-
Wide application range — Power tools, e-bikes, solar storage, LED lighting
-
High-current capability — Available in various current ratings
Technical Specifications
| # | Parameter | Specification |
|---|---|---|
| 1 | Compatible Battery | 6S 21.6V lithium-ion |
| 2 | Full Charge Voltage | 24.0V / 25.2V |
| 3 | Continuous Discharge Current | Variant dependent |
| 4 | Overcharge Protection Voltage | ~4.25V – 4.3V per cell |
| 5 | Over-discharge Protection Voltage | ~2.5V – 3.0V per cell |
| 6 | Balance Function | Yes |
| 7 | Connection Type | Solder pads (spot welding supported) |
| 8 | Module Dimensions | Compact PCB for 6S packs |
