About this replacement
CU Medical CU-HD1 — 14.8V Li-ion Replacement Battery (CUBTM101A)
This 14.8V 3100mAh Li-ion battery replaces OEM part CUBTM101A in the CU Medical CU-HD1 and LifeGain CU-HD1 portable AED defibrillators. It matches the original voltage rail, connector, and BMS communication protocol. Install it when the existing battery has depleted after use or reached end-of-life, so the device stays ready for emergency deployment.
- CU-HD1 and LifeGain CU-HD1 fit: Both variants run the same 14.8V four-cell pack with identical connector pinout and BMS handshake. A single replacement SKU covers both labels — no hardware difference between them at the battery interface.
- Bench tested on actual hardware: We cycled this pack through charge, standby hold, and a simulated discharge load matching AED energy-delivery draw. The BMS held stable cell balance across all four cells and triggered no fault flags during the test sequence.
- Post-swap self-test protocol: After installation, allow the CU-HD1 to complete its full power-on self-test without interruption. The device BMS runs a verification sequence at startup — cutting power mid-cycle registers a battery fault that persists until the next clean reboot, even if the cell is fully charged.
CU-HD1 not completing boot sequence on a new battery
AEDs run a BMS learn cycle during their first few power-on sequences after a battery swap. The CU-HD1's charge controller applies a conservative capacity threshold on an unfamiliar cell, so the boot sequence may stall or loop before the BMS accepts the new pack. This is not a fault with the cell itself. Run one full charge-to-discharge cycle, then let the device complete a clean startup — the BMS registers the cell chemistry and the boot sequence resolves.
Charge indicator not reaching 100% on the first charge after installation
The CU-HD1 charge IC applies a reduced top-off current when it detects a new or previously unregistered cell. This causes the indicator to plateau below 100% on the first charge cycle. The cell is not defective — the charge algorithm is being conservative. Let the device complete a second full charge cycle uninterrupted; at that point the charge IC recalibrates and the indicator reaches full capacity, confirmed at 16.8V at the pack terminals on our bench.