Inovytec VWSP-420 CPAP Replacement Battery 14.8V 2750mAh

Inovytec CPAP / HFNC Series — 14.8V Li-ion Replacement Battery (VWSP-420)

This 14.8V, 2750mAh (40.7Wh) Li-ion battery replaces OEM part VWSP-420 in Inovytec portable medical devices including CPAP, CPR, HFNC, and PC-SIMV units. It fits the same battery bay, uses the same connector, and communicates with the device BMS over the same data line as the original cell pack. Capacity is sourced from product data — 2750mAh at 14.8V nominal.

• Multi-mode Inovytec compatibility: The CPAP, HFNC, PC-SIMV, and CPR variants from Inovytec share the VWSP-420 form factor because they run off the same 14.8V power rail and use a common BMS handshake protocol. Swapping between modes does not change the battery requirement — the same pack powers all listed configurations.
• Bench tested on actual hardware: We cycled this cell pack through full charge and discharge on the Inovytec platform. The BMS completed its initialisation handshake without fault codes, and the protection circuit held cutoff at the correct low-voltage threshold under sustained airway-pressure load.
• Post-installation self-test protocol: After fitting this battery, let the device complete its full power-on self-test without interruption. Inovytec units run a BMS verification sequence at startup — cutting power mid-sequence logs a false battery fault that will not clear until the next clean reboot cycle.

Why the Inovytec alarms low battery immediately after a confirmed full charge

Medical device BMS firmware stores chemistry calibration data from the OEM cell pack. When a new cell is installed, the BMS has no stored capacity baseline for it and applies a conservative threshold that can trigger a low-battery alarm even at full charge. This is not a cell fault — it is a learn-cycle gap. Run one complete charge-discharge-recharge cycle without interruption and the BMS recalibrates its threshold against the new cell's actual capacity curve. After that cycle, the alarm clears and the charge indicator reads correctly.

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

Li-ion cells self-discharge during storage. If the VWSP-420 pack drops below approximately 10.0V — the per-cell deep-discharge threshold — the Inovytec BMS will refuse to boot and the device shows no response at all. Place the battery on charge immediately and leave it connected for a full cycle without attempting to power the device on. The charge IC applies a trickle pre-charge phase to recover cells below that threshold before handing over to the main charge stage. Once the pack reaches 12.5V or above, the BMS will re-enable the boot sequence normally.