About this replacement
Kenz Cardico Cardico 1210 / 1211 / 1210c — 12V Ni-MH Replacement Battery (HHR-11F25G1)
This is a 12V 3500mAh Ni-MH replacement battery for the Kenz Cardico Cardico 1210, 1211, and 1210c portable ECG machines. It replaces OEM part numbers HHR-11F25G1 and HHR-38AF25G1. The battery slots into the same compartment and connects to the same BMS interface as the original cell pack.
- Cardico 1210 / 1211 / 1210c platform fit: All three models run the same 12V power rail, use the same physical connector, and communicate with the same BMS handshake protocol — so one cell pack covers the entire Cardico series listed here.
- Bench tested on actual hardware: We cycled this battery through charge and discharge on a Cardico 1210 unit. The BMS accepted the cell, completed its initialisation sequence, and reported state-of-charge accurately after the first full cycle.
- Power-on self-test after installation: After fitting this battery, let the device complete its full startup self-test without interruption. The Cardico's BMS runs a chemistry verification at boot — cutting power during that sequence stores a false battery fault that persists until the next clean reboot.
Why the Cardico 1210 reports low battery immediately after a confirmed full charge
The Cardico's charge IC was calibrated for the OEM cell's internal resistance profile. A new replacement cell has a slightly different impedance signature on the first few cycles, which the BMS reads as a lower state-of-charge than the cell actually holds. This is not a fault with the battery — it is the BMS applying a conservative threshold against an unlearned cell. Run one complete charge-to-discharge cycle before relying on the charge indicator for clinical decisions. After that cycle, the BMS recalibrates and the display tracks correctly.
Cardico 1210 not completing boot sequence after battery was left in storage
Ni-MH cells self-discharge in storage, and the Cardico's BMS has a minimum recovery threshold — typically around 10.5V — below which it blocks startup to protect the device circuitry. If the cell dropped below that threshold while stored, the device will stall before completing the boot sequence. Connect the unit to mains power and leave it on charge for at least two hours before attempting to power on from battery alone. If the charge indicator still shows no activity after 30 minutes on charge, check that the connector is fully seated and the terminal voltage reads above 10.5V with a multimeter.