The 6S 24V 40A Lithium Battery Protection Board with Integrated BMS is a high-power safety module designed to protect 6-cell (6S) lithium-ion battery packs from overcharge, over-discharge, and overcurrent conditions. With a 40A continuous discharge rating and balance function, this BMS is engineered for high-drain applications including solar lighting systems, power tools, e-bikes, and energy storage systems where standard protection boards cannot handle the current requirements.
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 in demanding applications.
The board provides three critical protection functions:
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Overcharge protection — Disconnects the charger when any cell voltage reaches approximately 4.25V to 4.3V, preventing damage from excessive charging.
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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.
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Overcurrent protection — Disconnects the output when current exceeds 40A, 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 22.2V and a full charge voltage of 25.2V, commonly referred to as 24V systems. This voltage range is ideal for solar lighting systems, power tools, e-bikes, and other applications requiring higher voltage than 5S packs.
The 40A continuous rating makes this board suitable for high-power applications such as solar lighting, power tools, e-bikes, and energy storage systems. This is a significant step up from standard 6S boards that typically max out at 10A–20A, filling an important gap for high-current 6S applications.
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:
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Solar lighting systems — High-current protection for solar street lights and garden lights
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Power tools — High-current protection for drills, saws, and other tools
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E-bikes — High-power protection for electric bicycles
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Energy storage systems — Protect 6S battery packs in solar storage
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Portable power stations — High-current protection for portable power
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Electric scooters — Safe power for personal mobility devices
Important Note: This BMS is designed for 6S (6-cell) 24V lithium battery packs with a maximum continuous current of 40A. For higher-current applications, a BMS with a higher current rating 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 high-power 6S battery pack for a solar lighting system, assembling a power tool battery, or adding safety protection to an energy storage system, the 6S 24V 40A Lithium Battery Protection Board provides a reliable, high-power solution. It is suitable for individual makers, engineers, and businesses purchasing in bulk for product development or industrial applications.
Features
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6S six-cell protection — Manages six cells in series with cell balancing
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40A continuous discharge — High-power capability for demanding applications
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Balance function — Ensures even charge and discharge across all six cells
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Comprehensive protection — Overcharge, over-discharge, and overcurrent protection
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Integrated BMS design — Compact, self-contained protection solution
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Wide voltage range — 22.2V nominal / 25.2V full charge (24V systems)
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Solder pad design — Supports both direct soldering and spot welding
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Wide application range — Solar lighting, power tools, e-bikes, energy storage
Technical Specifications
| # | Parameter | Specification |
|---|---|---|
| 1 | Compatible Battery | 6S 22.2V lithium-ion |
| 2 | Full Charge Voltage | 25.2V |
| 3 | Continuous Discharge Current | 40A |
| 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 |
