Panasonic FZ-VZSU94K Toughpad FZ-M1 Replacement Battery 7.2V 3200mAh

Panasonic Toughpad FZ-M1 / FZ-B2 — 7.2V Li-Polymer Replacement Battery (FZ-VZSU94K)

This is a 7.2V, 3200mAh (23.04Wh) lithium-polymer replacement battery for the Panasonic Toughpad FZ-M1, FZ-M1C, and FZ-B2 rugged tablets. It replaces OEM part numbers FZ-VZSU94K, FZ-VZSU95K, FZ-VZSU95Q, FZ-VZSU94W, FZ-VZSU95W, and related variants. Drop it in when the original cell no longer holds enough charge for a full field shift.

• FZ-M1 and FZ-B2 compatibility: Both models run the same 7.2V battery rail with an identical connector footprint and BMS handshake protocol. The EEPROM in the replacement cell carries the chemistry and capacity data the tablet firmware expects — no adapter or firmware patch required.
• Bench tested on actual hardware: We cycled this cell in an FZ-M1 unit under a mixed CPU and display load. The BMS held the charge curve through to full capacity without tripping the tablet's protection circuit or triggering a low-voltage cutoff prematurely.
• First-cycle calibration on the FZ-M1: After installing, run one full discharge until the tablet hibernates, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle on the FZ-M1 and clears the inaccurate health warning that appears on most cell swaps. Skip this step and the fuel gauge IC will report stale data from the old cell for weeks.

Why the FZ-M1 shuts down at 20–30% after a battery swap

The Toughpad FZ-M1 uses a fuel gauge IC that learns the discharge curve of the installed cell over multiple cycles. When you swap the battery, the IC still has the old cell's voltage-to-capacity map in memory. Under a combined CPU and display load, voltage drops faster than the old map predicts, and the firmware hits its shutdown threshold well before the cell is actually empty. Run two to three full charge-discharge cycles and the gauge recalibrates to the new cell's actual voltage cliff — typically around 6.0V under load.

BIOS reporting battery health as "poor" or "replace soon" immediately after install

This is an EEPROM data mismatch, not a faulty cell. The FZ-M1's battery management firmware reads cycle count and health state from the cell's EEPROM on first contact. A new cell starts with a fresh EEPROM that hasn't completed the learn cycle the BIOS expects to see. The health flag clears after the BIOS completes its battery learn cycle — trigger this by fully discharging to hibernate cutoff and then charging to 100% without interruption. Check the Battery Status page in Panasonic's PC Information Viewer after the first full charge to confirm the flag has cleared.