4S 30A BMS LiFePO4 Lithium Battery Protection Board with Balance

4S 30A BMS Battery Protection Board with Cell Balancing

Keep your lithium battery packs running safely and efficiently with this 4-cell (4S) Battery Management System (BMS) protection board. Designed for both LiFePO4 (3.2V, 12.8V total) and standard lithium-ion (3.7V, 14.8V total) chemistries, it delivers 30A continuous current handling along with built-in active cell balancing — making it an ideal choice for 18650, 32650, and similar cylindrical battery pack builds.

Made in Mainland China.

Why You Need a Quality BMS

A Battery Management System is the essential safeguard between your battery cells and your devices or load. Without proper protection, lithium cells are vulnerable to overcharge, over-discharge, overcurrent, and thermal runaway. This board monitors and manages all of these conditions automatically, extending the life of your battery pack and keeping your build safe.

Key Features

• Compatible Chemistries: LiFePO4 (3.2V per cell / 12.8V pack) and Lithium-Ion (3.7V per cell / 14.8V pack)
• 4S Configuration: Supports 4 cells in series for 12.8V or 14.4–14.8V battery packs
• 30A Continuous Current Rating: Handles demanding loads with stable performance
• Built-In Cell Balancing: Equalizes individual cell voltages during charging for longer cycle life and improved capacity
• Overcharge Protection: Automatically disconnects when cells reach maximum voltage
• Over-Discharge Protection: Cuts off output before cells drop to damaging voltage levels
• Overcurrent & Short-Circuit Protection: Instantly responds to fault conditions to protect both the board and your cells
• Compact SMD Design: Space-saving surface-mount construction for easy integration into custom battery packs
• Available in 1, 2, or 3-Pack Quantities: Stock up for multiple builds or share with a project partner

Specifications

• Configuration: 4S (4 cells in series)
• Compatible Cell Voltages: 3.2V (LiFePO4) / 3.7V (Li-ion)
• Pack Voltages: 12.8V (LiFePO4) / 14.4–14.8V (Li-ion)
• Continuous Discharge Current: 30A
• Compatible Cell Formats: 18650, 32650, and similar cylindrical cells
• Balancing: Yes (passive/active balancing included)
• Package Type: SMD
• Condition: New
• Origin: Mainland China

What's in the Box

• 1, 2, or 3 × BMS 4S 30A Protection Board with Balance (depending on quantity selected)

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Frequently Asked Questions

Q: Is this BMS board compatible with both LiFePO4 and standard lithium-ion (18650) batteries?

A: Yes! This 4S BMS protection board supports both LiFePO4 cells (3.2V per cell, 12.8V pack) and standard lithium-ion cells (3.7V per cell, 14.4–14.8V pack), including popular formats like 18650 and 32650 cylindrical cells. Just ensure you select or configure the correct voltage thresholds for your cell chemistry.

Q: What does the cell balancing feature do?

A: Cell balancing ensures that all four cells in your series pack charge and discharge evenly. Over time, individual cells can drift apart in voltage, reducing overall pack capacity and potentially damaging weaker cells. The built-in balancing circuit corrects these differences during charging, maximizing pack longevity and usable capacity.

Q: Can this board handle 30A continuous discharge?

A: Yes, this BMS is rated for 30A continuous discharge current. It is well-suited for moderate-to-high power applications such as electric tools, DIY power banks, solar storage, and more. Always ensure your wiring and connectors are also rated to handle the current you plan to draw.

Q: How many boards will I receive?

A: You can choose from a 1-pack, 2-pack, or 3-pack quantity at checkout. This is ideal whether you need a single board for a project or want spares or multiple builds.