Active Battery Balancer (5.5A)

Keep your pack in tune. This active “flying-capacitor” balancer moves energy from higher-voltage cells to lower-voltage cells, boosting usable capacity and helping your cells age evenly. Ideal for 48–60V DIY packs in solar, storage, and light EV projects.

• Active equalization: Transfers charge cell-to-cell instead of burning it off as heat.
• Fast balancing: Up to ~5.5A when the pack is out of balance; current tapers as cells converge.
• Wide chemistry support: LiFePO4 (LFP), NMC/NCM, and LTO.
• Low standby draw: ~12 mA quiescent; sleep mode <0.1 mA.
• Tight accuracy: Balance voltage accuracy within ~5 mV.

Specifications

• Accessory Type: Battery Balancer (Active)
• Chemistries: LFP (LiFePO⁴), NMC/NCM, LTO
• Cells in Series: 12–16S (selectable)
• Balancing Current: 0–5.5 A (tapers as cells equalize)
• Per-Cell Working Voltage: 1.8–4.5 V
• Sleep Current: <0.1 mA (manual sleep switch)
• Quiescent Current: ~12 mA
• Recommended Pack Capacity: 60–300 Ah
• PWB: 2 oz copper, low-R_DS(on) MOSFETs
• Certification: CE
• Battery Included: No
• Charger Included: No
• Brand: Heltecbms
• Origin: Mainland China

Features

Capacitor-based charge transfer equalizer designed for fast, energy-efficient balancing across 12–16 series cells.
Uses ultra-low resistance MOSFETs and a 2 oz copper PCB for high transfer efficiency.
Manual sleep function; balance accuracy within ~5 mV for tight pack convergence.
Undervoltage sleep protection automatically pauses balancing below ~3.0 V per cell.

Battery Type Settings

Board jumpers define chemistry and run state:
Left pad short: LTO mode  |  Right pad short: Ternary (NMC/NCM) & LFP mode
RUN shorted: Enable equalization  |  Open: Stop balancing

Connection

Notes & Best Practices

• This is an active balancer, not a BMS or charger. Use with a proper BMS for protection.
• Wire carefully to the correct cell taps (B-, B1, B2 … B16). Incorrect order can damage the board.
• Use one balancer per series string. Do not share a single balancer across parallel sub-strings.
• High transfer current can reveal weak cells or poor connections—verify cell health and busbar torque.