2S 3S 4S Active Battery Balancer 1.2A Inductive Equalizer Module

2S / 3S / 4S Active Battery Balancer Board – 1.2A Inductive Energy Transfer Equalizer

Keep your lithium battery pack performing at its peak with the KOQZM 2S/3S/4S Active Balancer Board. Using inductive energy transfer technology, this module automatically detects voltage differences between adjacent cells and redistributes energy to equalize them — extending the life of your battery pack and maximising overall efficiency. Compatible with LiFePO4, LiPo, and Li-ion ternary lithium batteries.

Made in Mainland China.

How It Works

This board operates on the principle of adjacent cell equalization. When the voltage difference between two neighbouring cells exceeds 0.1V, the onboard chip automatically triggers balancing. It continues transferring energy between cells until the voltage difference drops to within 0.03V, then enters sleep mode. No manual intervention required — it works seamlessly during both charging and discharging cycles.

• ✅ Trigger threshold: Voltage difference > 0.1V → balancing current ~0.5–0.7A
• ✅ Maximum balance current: 1.2A (when voltage difference > 0.2V)
• ✅ Stop threshold: Voltage difference ≤ 0.03V (enters sleep mode)
• ✅ Working voltage range: 2.0V – 4.5V per cell
• ✅ Compatible with: 2S, 3S, or 4S lithium battery packs (LiFePO4, LiPo, Li-ion ternary)
• ⚠️ NOT compatible with LTO (Lithium Titanate) batteries

LED Status Indicators

Wiring Guide

• B−: Total negative pole of the battery pack (negative of Cell 1)
• B1: Positive pole of Cell 1
• B2: Positive pole of Cell 2
• B3: Positive pole of Cell 3
• B4: Positive pole of Cell 4

⚠️ Important: For configurations of 13S or more, the cable plug must be inserted at an angle — make contact with the B− pin first, then insert upward at an angle. Failure to do so may damage the board.

Key Specifications

• Brand: KOQZM
• Configuration: 2S / 3S / 4S
• Balance Current: Up to 1.2A
• Working Voltage: 2.0V – 4.5V
• Battery Types: LiFePO4, LiPo, Li-ion (ternary)
• Equalization Principle: Inductive adjacent cell energy transfer
• Origin: Made in Mainland China

Important Precautions

This board is not a standalone battery maintenance tool. It must always be used in conjunction with a compatible lithium battery protection board (BMS). The equalizer is triggered by the voltage differences generated during normal charge and discharge cycles — it is designed for ongoing cell balancing within a battery pack, not for recovery of deeply discharged cells.

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For further reading on lithium battery safety and best practices, refer to the U.S. Consumer Product Safety Commission – Lithium Battery Safety Information.

Frequently Asked Questions

Q: What types of lithium batteries are compatible with this active balancer board?

A: This 2S/3S/4S active balancer board is compatible with LiFePO4, LiPo, and Li-ion ternary lithium batteries with a working voltage range of 2.0V–4.5V per cell. It is not compatible with LTO (Lithium Titanate Oxide) batteries.

Q: Does this balancer board replace a BMS (Battery Management System)?

A: No. This board is designed to work alongside a lithium battery protection board (BMS), not as a replacement. The BMS handles overcharge, over-discharge, and short-circuit protection, while this equalizer focuses on balancing the voltage across adjacent cells during charge and discharge cycles.

Q: How do I know when the balancer is actively equalizing?

A: The onboard LED indicator tells you everything — a solid light means equalization is in progress, no light means the cells are balanced and the board is in sleep mode, and a flashing light indicates a potential string drop or circuit fault that should be investigated.

Q: What is the maximum balancing current this module can deliver?

A: When the adjacent cell voltage difference exceeds 0.2V, this module delivers a maximum balancing current of 1.2A. At smaller differences (above 0.1V), the current is approximately 0.5–0.7A and decreases proportionally as the cells approach equilibrium.