ResMed Astral 150 Ventilator Ultralife 14.4V Compatible Battery

ResMed Astral 150 Ventilator Ultralife — 14.4V Li-ion Replacement Battery (R270-7417)

This is a 14.4V, 9000mAh (129.6Wh) lithium-ion battery for the ResMed Astral 150 Ventilator. It fits the Astral 150 Ultralife configuration and matches the OEM connector, voltage rail, and BMS handshake required by the device. Use it for in-facility backup power or patient transport where mains power is unavailable.

• Astral 150 Ultralife compatibility: The Astral 150 uses a tightly managed 14.4V bus with a proprietary BMS handshake that rejects cells outside its accepted voltage window. This cell matches that window exactly — part numbers R270-7417 and R270-366/1 both reference this battery across different regional variants of the device.
• Bench tested on actual hardware: We ran this battery through full charge-discharge cycles on the Astral 150 platform and confirmed the BMS completed its verification sequence without fault codes. The protection circuit responded correctly to load transitions typical of ventilator motor demand.
• Post-installation self-test cycle: After fitting this battery, allow the Astral 150 to complete its power-on self-test without interruption. The device runs a BMS verification pass at startup — cutting power during this sequence logs a false battery fault that persists until the next full reboot cycle.

Why the Astral 150 flags a battery fault on a new cell

The Astral 150 uses a charge-state authentication check during startup. New lithium-ion cells ship at a partial state of charge — typically 40–60% — and the device BMS compares the reported capacity against its OEM baseline. If the cell hasn't completed a full charge-discharge cycle, the reported capacity sits below the device's minimum acceptance threshold. This triggers a battery fault flag even though the cell is functional. One full charge-discharge cycle resets the BMS learn register and clears the fault on subsequent startups.

Charge indicator stalls below 100% on first charge

On the first charge, the Astral 150's charge IC applies a conservative current limit to an unrecognised cell — it holds the termination voltage lower than normal until the BMS confirms cell behaviour matches expected parameters. This makes the indicator appear to stall at 85–95% and never reach full. The fix is to leave the device on charge past the apparent stall point — the charge IC typically releases the limit and completes the cycle within two to three hours. After the first full cycle, subsequent charges reach 100% at normal speed.