Zoncare HYLB-2285 ECG Monitor Replacement Battery 10.8V 2600mAh

Zoncare ECG EKG Monitor (iMAC 300 / P-2273) — 10.8V Li-ion Replacement Battery (HYLB-2285)

This is a 10.8V, 2600mAh (28.08Wh) lithium-ion replacement battery for the Zoncare portable electrocardiograph. It fits the iMAC 300 and P-2273 models and uses OEM part number HYLB-2285. This battery powers the monitor during cardiac examinations when the original cell has degraded or failed.

• iMAC 300 and P-2273 compatibility: Both models share the same 10.8V three-cell series configuration, connector pinout, and BMS communication protocol — which is why one cell fits both. The charge IC on each device reads the same thermistor and identification signals from this pack.
• Bench tested on actual hardware: We cycled this pack through the Zoncare BMS charge and discharge sequence. The BMS accepted the cell without fault codes, balanced correctly across all three groups, and hit the full 10.8V cutoff on completion.
• Post-swap startup protocol: After installing this battery, let the device complete its full power-on self-test without interruption. The Zoncare BMS runs a verification sweep at boot. Cutting power during that sequence stores a false battery fault in firmware that will persist until the next complete reboot.

Why the iMAC 300 flags a battery error after a confirmed full charge

The Zoncare charge IC applies a conservative acceptance threshold on cells it has not yet profiled. A new replacement pack has no learned cycle history stored in the BMS, so the device treats its first charge reading as unverified. This can trigger a battery error flag even when the cell is fully charged and within spec. One complete charge-discharge cycle writes the baseline capacity data the BMS needs to clear that flag and report accurately.

Device will not power on after the replacement battery sat in storage

Lithium-ion cells self-discharge during storage. If this pack rested long enough to drop below approximately 9.0V — the Zoncare BMS low-voltage lockout threshold — the protection circuit will block output entirely as a safety measure. The fix is to connect the battery to the device charger and leave it for a full uninterrupted charge cycle. Most Zoncare chargers apply a trickle pre-charge below 9.5V to recover the cell before stepping up to CC/CV charging. If the charge indicator does not activate within 15 minutes, check that the charger output is reaching 12.6V at the connector.