Acorn 10/5000DH-C-SL Stairlift Replacement Battery 12V 5000mAh

Acorn 180 Stairlift — 12V Ni-MH Replacement Battery (10/5000DH-C-SL)

This is a 12V, 5000mAh Ni-MH replacement battery for the Acorn Stairlift range, including the 180 Stairlift, 80 Stairlift, and Bison Bede Bison 80 Stairlift. It replaces OEM part numbers 10/5000DH-C-SL and OM0104. The battery powers the stairlift's drive motor and onboard control systems.

• Acorn 180 and 80 Stairlift platform compatibility: These models share the same 12V battery rail, connector format, and BMS handshake protocol. A single pack covers the full range because the control board draws from the same voltage bus regardless of track length or chair configuration.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a stairlift control board. The BMS accepted the pack without fault codes, completed its verification handshake, and the motor drive circuit responded normally under load.
• Post-installation self-test protocol: After fitting this battery, let the stairlift complete its full power-on self-test without interrupting power. The control board runs a BMS verification sequence at startup. Cutting power mid-sequence sets a persistent battery fault that does not clear until the next full uninterrupted reboot cycle.

Why the Acorn Stairlift triggers a low-battery alarm with a new pack installed

The Acorn stairlift control board uses a charge threshold calibrated to its OEM cell's internal resistance profile. A new Ni-MH cell starts with a slightly different resistance signature than a conditioned pack. The BMS reads this as a sub-threshold state of charge and trips the alarm even when the battery is fully charged. One complete charge-discharge cycle normalises the cell's resistance curve, and the alarm clears on subsequent use.

Stairlift won't power on after the replacement battery sat in storage

Ni-MH cells self-discharge during storage. If this pack sat for several months before installation, its resting voltage may have dropped below the stairlift BMS's minimum recovery threshold — typically around 10.5V for a 12V system. At that voltage the BMS locks out the circuit as a protection measure and the chair appears completely dead. Connect the charger and leave it on a full uninterrupted charge cycle before attempting to power the unit on. If the charger confirms a completed charge and the unit still does not respond, check the pack voltage directly at the battery terminals — it should read at least 12.0V before the BMS will allow the motor circuit to activate.