MEDIMEX INC PD-1 Replacement Battery 12V 2300mAh SLA

MEDIMEX INC PD-1 / LS 285 Defibrillator — 12V Sealed Lead Acid Replacement Battery

This is a 12V, 2300mAh (27.6Wh) sealed lead-acid replacement battery for the MEDIMEX INC PD-1 and LS 285 Defibrillator. It fits the internal battery bay directly and matches the original voltage and capacity spec. This battery is intended for clinical and emergency-use environments where the original cell has degraded or failed.

• PD-1 and LS 285 compatibility: Both devices share the same 12V sealed lead-acid platform, battery bay dimensions, and connector interface. The BMS on each device reads terminal voltage and internal resistance at startup — this cell matches that handshake without modification.
• Bench tested on actual hardware: We ran a full charge-discharge cycle and confirmed the BMS accepted the cell, cleared the low-battery flag, and held voltage within spec under a simulated clinical load. The first cycle calibrates the charge IC to the new cell's internal resistance curve.
• Post-installation self-test protocol: After fitting this battery, allow the device to complete its full power-on self-test without interruption. The LS 285 and PD-1 run a BMS verification routine at boot — cutting power mid-sequence writes a false battery fault that persists until the next complete reboot cycle.

Defibrillator not completing boot sequence on new battery

The PD-1 and LS 285 run a startup self-test that checks resting terminal voltage before allowing full boot. A new sealed lead-acid cell can sit below the BMS acceptance threshold if it discharged during storage — even slightly. The device interprets this as a failed or missing battery and halts the boot sequence. Connect the device to mains power first, allow the battery to charge fully, then reboot without interrupting the self-test cycle.

Charge indicator not reaching 100% on the first charge cycle

On the first charge, the LS 285's charge IC applies a conservative current limit while it reads the new cell's impedance. This causes the indicator to stall — typically between 85–95% — before the algorithm adjusts. It is not a faulty cell or a faulty charger. Run one complete charge-discharge cycle and the charge IC will recalibrate; the indicator will reach 100% on the second charge. Do not use the device clinically until this first full cycle is complete.