G-CARE SP-800 Medical Device Compatible Battery 7.2V 2600mAh

G-CARE SP-800 — 7.2V Li-ion Replacement Battery (BAK-18650C4*2)

This 7.2V, 2600mAh Li-ion battery replaces the original pack in the G-CARE SP-800 portable medical monitoring device. It uses two 18650 cells in series to match the SP-800's voltage rail and connector spec. Capacity is 2600mAh (18.72Wh), identical to the factory pack.

• SP-800 platform fit: The SP-800 draws from a dual-cell 7.2V series configuration with a BMS that validates cell chemistry at startup. This pack uses matched BAK 18650 cells at the same nominal voltage, so the BMS handshake completes without a fault code on boot.
• Bench tested on actual hardware: We cycled this pack through charge, standby, and load draw sequences mirroring clinical use. The BMS held charge termination correctly and triggered no undervoltage cutoff during simulated monitoring sessions.
• Post-installation startup protocol: After fitting this pack, allow the SP-800 to complete its full power-on self-test without interruption. The device runs a BMS verification sequence at every boot — cutting power mid-sequence plants a false battery fault that won't clear until the next clean reboot.

Device not completing boot sequence after battery swap

The SP-800 runs a self-test at startup that checks cell voltage against a minimum threshold before it will proceed past the boot screen. A new cell that has partially self-discharged during storage can sit just below that threshold — enough to stall the boot sequence even though the pack is not empty. Charge the replacement fully before first installation, then power the device on and leave it undisturbed through the entire self-test cycle. Once the device reaches its main operating screen, the BMS registers the pack as valid and the issue does not recur.

Charge indicator stalls and never reaches 100% on first charge

On the first charge cycle, the SP-800's charge IC applies a conservative current limit to new cells — this is a calibration behaviour, not a fault. The charge counter can stall at 95–99% for an extended period before the indicator flips to full. Do not interrupt the charge or remove the pack early. Let the cycle complete to termination voltage (4.2V per cell), which the BMS uses as the baseline for all subsequent state-of-charge calculations. Interrupting this first cycle causes the fuel gauge to read inaccurately on every subsequent charge.