About this replacement
Philips TC10 / TC20 — 11.1V Li-ion Replacement Battery (989803185291)
This 11.1V 4800mAh Li-ion battery replaces the OEM pack in the Philips TC10 and TC20 portable patient monitors. It covers ECG, SpO₂, heart rate, and blood pressure monitoring duties during transport or when mains power is unavailable. Capacity is 4800mAh (53.28Wh), matching the original specification from Philips part numbers 989803185291, 453564402681, and 0411001.
- TC10 and TC20 platform fit: Both monitors share the same battery bay geometry, connector pinout, and BMS communication protocol. One replacement pack covers either unit without modification.
- Bench tested on actual hardware: We cycled this pack through the TC10 boot sequence and monitored BMS handshake behaviour under clinical load. The protection circuit handled the device's multi-parameter polling correctly, with no voltage drop events flagged during the test cycle.
- Post-installation self-test protocol: After fitting this battery, allow the TC10 or TC20 to complete its full power-on self-test without interruption. The device runs a BMS verification step at startup — cutting power during this window triggers a false battery fault that persists until the next clean reboot.
Device not completing boot sequence on a new battery
The TC10 runs a BMS learn cycle on first use with a new cell. If the pack shipped or sat in storage at a reduced state of charge, the device may halt partway through boot and display a battery fault. This is not a dead pack — the BMS has not yet verified the cell's capacity curve against its internal threshold. Charge the battery fully before the first boot attempt, then allow the self-test to run without interruption.
TC10 low-battery alarm firing immediately after a confirmed full charge
This happens when the BMS threshold check runs before the new cell has completed one full charge-discharge cycle. The TC10's charge IC applies a conservative verification limit on unfamiliar cells, and the first cycle often reads slightly below the alarm threshold. Run one complete charge and discharge cycle under normal device use before treating any alarm as a genuine fault. After that first cycle, the alarm behaviour normalises and the pack registers correctly at 11.1V nominal.