TSI INC Certifier FA Plus Replacement Battery BLI-195 7.4V

TSI INC Certifier FA Plus Ventilator — 7.4V Li-ion Replacement Battery (BLI-195)

This 7.4V 2200mAh Li-ion battery replaces the OEM pack in the TSI INC Certifier FA Plus Ventilator and the Certifier Flow Analyzer Plus Ventilator Test System 4080. It matches the original BLI-195 and B11876 part numbers in voltage, cell chemistry, and connector. Capacity is 2200mAh (16.28Wh), sourced directly from the product specification.

• Certifier FA Plus and 4080 compatibility: Both the Certifier FA Plus and the Flow Analyzer Plus 4080 share the same 7.4V battery bay, connector pinout, and BMS communication protocol — which is why one cell pack covers both models without modification.
• Bench tested on actual hardware: We cycled this cell through full charge and discharge on the Certifier platform. The BMS handshake completed normally, charge acceptance reached full capacity by cycle two, and no false fault codes were triggered during the self-test sequence.
• Post-swap startup protocol: After installing this battery, let the Certifier complete its full power-on self-test without interruption. The device runs a BMS verification routine at startup — cutting power mid-sequence causes a persistent battery fault flag that won't clear until the next clean reboot.

Why the Certifier FA Plus shows a battery fault after a confirmed full charge

The Certifier's BMS stores a capacity baseline from the previous cell and compares incoming charge acceptance against that threshold. A new Li-ion cell has slightly higher internal resistance than a broken-in cell, so the BMS may flag a fault even when the pack is fully charged. This isn't a defective battery — it's the BMS applying an OEM-calibrated threshold to an unfamiliar cell. Run one complete charge-discharge cycle and the BMS recalibrates its baseline to match the new cell's chemistry profile.

Certifier FA Plus not powering on after the battery sat in storage

Li-ion cells self-discharge during storage and can drop below the BMS recovery threshold — typically around 2.5V per cell, or 5.0V for a 7.4V 2S pack. When voltage falls below that floor, the BMS locks out discharge to prevent cell damage, and the device won't respond to the power button. Place the battery on a compatible charger and leave it connected for at least 30 minutes — most charge ICs apply a low-current trickle recovery mode below 3.0V per cell before switching to standard CC/CV charging. Once cell voltage recovers above 5.0V, the BMS unlocks and the device boots normally.