Artisan PMS Lasair II 310 Replacement Battery 14.4V 7800mAh

Artisan PMS Lasair II 310 Series — 14.4V Li-ion Replacement Battery

This 14.4V Li-ion battery replaces the internal power pack in the PMS Lasair II 310, 310B, 350L, and 550L portable particle counters. Capacity is 7800mAh (112.32Wh). These are handheld air particle detection instruments used in pharmaceutical cleanrooms and medical device manufacturing lines where continuous uptime matters.

• Lasair II 310, 310B, 350L, and 550L compatibility: All four models share the same 14.4V battery platform, connector pinout, and BMS communication protocol. The cell pack slots into the same battery bay across the series with no modification required.
• Bench tested on actual hardware: We cycled this battery through charge and discharge on the Lasair II 310 platform and confirmed the BMS handshake completes correctly. The protection circuit held cutoff within spec at both ends of the voltage window.
• Power-on self-test after installation: After installing this battery, let the Lasair II run through its full startup self-test cycle without interruption. The device runs a BMS verification pass at boot — cutting power mid-sequence triggers a persistent battery fault that will not clear until the unit completes a clean reboot from a full charge.

BMS learn cycle on the Lasair II and why the first 10 cycles matter

The Lasair II 310's charge management system tracks cell behaviour over successive cycles to build an accurate state-of-charge model. A fresh cell does not match the stored chemistry profile from the previous battery, so the BMS applies conservative charge and discharge limits until it logs enough cycle data. During those first cycles, the unit may report lower capacity than the cell actually holds. Run the instrument through at least one full charge-discharge cycle before using it in a clinical or cleanroom qualification run — the BMS model stabilises and reported capacity aligns with actual cell output by cycle 3 to 5.

Charge indicator not reaching 100% on the first charge

On first charge, the Lasair II's charge IC applies a reduced current ceiling to a cell it has not yet profiled, which means the charge termination voltage is hit before the cell is fully conditioned. The display may stop at 90–95% and hold there. This is not a fault with the battery or the charger circuit. Run a full discharge under normal operating conditions and then recharge completely — the charge IC recalibrates its termination threshold, and subsequent charges will reach 100%.