Laerdal LCSU4 12V 2000mAh Replacement Battery 88005101

Laerdal LCSU4 / LCSU3 Suction Units — 12V Ni-MH Replacement Battery (88005101)

This is a 12V 2000mAh Ni-MH replacement battery for the Laerdal LCSU4 and LCSU3 portable suction units. It fits the emergency airway clearance devices used in patient transport, pre-hospital care, and clinical settings. Capacity is 24Wh, matching the original power specification for these units.

• LCSU3 and LCSU4 platform compatibility: Both generations share the same 12V Ni-MH chemistry, connector pinout, and BMS handshake protocol. The cell replacement covers OEM references 88005101, 88006101, 88005001, 88006001, 886113, 88007005, and 110517-O without hardware modification.
• Bench tested on actual hardware: We cycled this cell through the LCSU4 charge controller and confirmed the BMS accepted the new cell without a persistent fault flag. Charge current tapered correctly at end-of-charge, and the device cleared its power-on self-test on the second full cycle.
• Post-installation self-test protocol: After fitting this battery, allow the LCSU4 to complete its full power-on self-test without interruption. Cutting power mid-sequence causes the BMS to log a battery fault that persists across reboots — the unit will flag low battery even on a fully charged cell until a clean boot cycle clears it.

Why the LCSU4 self-test fails after a battery swap

The LCSU4 runs a BMS verification routine at startup that checks cell voltage against a minimum threshold calibrated for aged OEM cells. A new Ni-MH cell can present a slightly different open-circuit voltage signature, causing the self-test to flag a mismatch on the first boot. This is not a defective battery — it is the charge IC applying a conservative evaluation to an unconditioned cell. Run one full charge-discharge cycle through the device before treating any self-test result as definitive. After conditioning, the BMS learn cycle completes and the unit boots cleanly.

LCSU4 alarming low battery immediately after a confirmed full charge

This happens when the BMS samples cell voltage during the high-current draw of the suction motor starting up. Ni-MH cells show a sharper voltage sag under load in the first several cycles than a conditioned cell does, and the protection circuit interprets that sag as a low-charge condition. The alarm clears once the cell has completed three to five full charge-discharge cycles and internal resistance drops. Confirm charge status by checking that the charge indicator light has extinguished and the cell resting voltage reads at or above 13.5V before use.