About this replacement
Philips G40 / GS10 / GS20 Series — 11.1V Li-ion Replacement Battery (LI3S200A)
This is an 11.1V, 4800mAh Li-ion replacement battery for the Philips G40, G40E, GS10, and GS20 portable clinical monitors. It replaces OEM part number LI3S200A. Use this when the original cell no longer holds charge or fails the device's built-in battery self-test.
- G40, G40E, GS10, and GS20 compatibility: These models share the same 11.1V battery rail, LI3S200A connector, and BMS handshake protocol — one cell fits all four without modification or adapter.
- Bench tested on actual hardware: We cycled this cell through the G40's charge-discharge sequence and confirmed the BMS accepted the new cell, passed voltage threshold checks, and held charge across multiple full cycles without triggering a fault state.
- Post-swap self-test procedure: After installing this battery, allow the G40 to complete its full power-on self-test without interrupting it. The device runs a BMS verification at startup — cutting power mid-sequence registers a false battery fault that persists until the next complete reboot.
Device not completing boot sequence after battery swap
The G40's boot sequence includes a BMS handshake that checks cell voltage against an internal threshold before it will proceed. A new Li-ion cell fresh from storage can sit slightly below the BMS's minimum acceptable voltage — not because it's depleted, but because it hasn't been through a conditioning cycle. The device interprets this as a fault and halts the boot. Connecting the device to mains power first, letting the cell charge to above 11.5V, then rebooting clears this in most cases.
Low battery alarm triggering immediately after a confirmed full charge
This happens when the BMS has calibrated its state-of-charge reference against the previous degraded cell. The replacement cell has a higher actual capacity, but the BMS gauge doesn't yet know it — it reads the new cell's charge curve as unfamiliar and defaults to a conservative low-threshold alarm. Running one complete charge-discharge cycle lets the BMS recalibrate its internal model to the new cell's chemistry. After that cycle, the low battery alarm threshold realigns and the false trigger stops.