About this replacement
GE Responder 1000 / SCP 840 Series — 18V Ni-MH Replacement Battery (88888235)
This is an 18V 800mAh Ni-MH replacement battery for the GE Responder 1000 and Responder 1100 automated external defibrillators, as well as the SCP 840 and SCP 912. It matches OEM part numbers 88888235, 20510002, 15N-800AA, and 92916531. Voltage and cell count match the original pack exactly.
- Responder 1000 / SCP series compatibility: These models share the same 18V bus, connector pinout, and BMS handshake protocol. A single cell pack revision covers all four platforms without modification.
- Bench tested on actual hardware: We ran this pack through the Responder 1000 charge cycle and power-on self-test. The BMS recognised the pack, completed its initialisation sequence, and held voltage within the device's accepted band across the full self-test load.
- Power-on self-test after installation: After fitting the new pack, let the device run its complete startup self-test without interruption. The Responder 1000 runs a BMS verification pass at power-on — cutting power mid-sequence logs a battery fault that persists until the next full reboot and can delay device readiness.
Why the Responder 1000 flags a battery fault after a confirmed full charge
The Responder 1000's BMS uses a learned capacity threshold from the previous cell to pass the self-test. A new Ni-MH pack has not yet established that profile, so the device can reject it even at full charge voltage. This is a BMS learn-cycle issue, not a cell defect. Run one full charge-to-discharge-to-charge cycle outside clinical use. After that cycle, the BMS recalibrates its threshold to the new cell and the fault clears.
Device will not power on after the replacement pack sat in storage
Ni-MH cells self-discharge at roughly 1–2% per day at room temperature. A pack stored for several months can drop below the Responder 1000's minimum BMS recovery threshold — typically around 14V on an 18V pack — and the device will not boot. Place the pack on the OEM charger and allow a full charge cycle before attempting power-on. If the charger does not recognise the pack initially, verify the pack voltage with a multimeter; anything above 10V should trigger the charger's recovery mode and bring the pack back up.