Panasonic FZ-G1R Replacement Battery 11.1V 9600mAh

Panasonic FZ-G1R Series — 11.1V Li-ion Replacement Battery (FZ-VZSU84U)

This 11.1V 9600mAh Li-ion battery replaces the original cell in the Panasonic Toughbook FZ-G1R, FZ-G1A, FZ-G1B, and the iCON CS35 10. It matches the OEM voltage rail and physical footprint exactly. Capacity is 9600mAh (106.56Wh) as stated in the product specification.

• FZ-G1 series compatibility: The FZ-G1R, FZ-G1A, and FZ-G1B share the same battery bay geometry, 11.1V power rail, and BMS handshake protocol — which is why one cell covers all three. The connector and latch mechanism are identical across this generation of Toughbook tablets.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a Toughbook FZ-G1 unit. The BMS accepted the cell without fault codes, charge termination triggered correctly at full capacity, and the protection circuit responded to simulated overcurrent as expected.
• Toughbook battery learn cycle: After fitting, run a full discharge to hibernate cutoff, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning that appears after every cell swap in the FZ-G1 series.

BIOS reporting poor battery health immediately after fitting a new cell

The FZ-G1 BIOS reads health data from EEPROM registers that carry over from the old cell. When a new cell goes in, those registers still reflect the degraded state of the battery you just removed. The BIOS has not yet learned the new cell's actual capacity curve. Run one complete discharge-to-hibernate followed by a full uninterrupted charge — this forces the fuel gauge IC to recalibrate against the new chemistry. After two or three of these cycles, the health reading normalises.

Toughbook shuts down abruptly while the gauge still shows 20–25% charge

This is a voltage cliff failure. Under combined CPU load, display brightness, and radio activity, the cell voltage drops faster than the fuel gauge IC can track — the gauge shows 20% but the actual cell voltage has already fallen below the BMS cutoff threshold. It is not a faulty battery; it is an uncalibrated fuel gauge reading a new cell with old reference data. Run two full discharge-to-hibernate cycles followed by full charges. After calibration, the shutdown point and the displayed percentage will align — typically below 5%.