Mitsubishi T200 Replacement Battery 3.6V 1200mAh Ni-MH

Mitsubishi T200 / T250 / T255 — 3.6V Ni-MH Replacement Battery

This is a 3.6V, 1200mAh Ni-MH replacement battery for the Mitsubishi T200, T250, and T255 mobile handsets. All three models share the same battery bay dimensions and voltage rail, so one cell fits the full range. Capacity is rated at 4.32Wh — matching the original specification.

• T200 / T250 / T255 compatibility: These three handsets use the same physical cell format and 3.6V nominal voltage rail. The battery bay, contact orientation, and charge termination voltage are identical across the range — no modification needed to fit any of the three.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on T-series hardware. The charge termination circuit accepted the cell without fault flags, and the BMS completed a full cycle without tripping a protection cutoff.
• Ni-MH conditioning after installation: Ni-MH cells in low-use devices are prone to voltage depression if stored partially charged. After fitting, run two full discharge-charge cycles before relying on the battery percentage indicator — this conditions the cell and lets the fuel gauge recalibrate against the actual discharge curve.

Why the T200 reports the wrong battery percentage after a cell swap

The T200's fuel gauge IC builds its capacity model from cumulative charge and discharge data on the original cell. When you fit a new cell, that learned curve no longer matches the actual cell chemistry. The gauge reads voltage and estimates remaining capacity against the old model, so it displays inaccurate percentages — often reading full when the cell is not. One complete discharge-charge cycle forces the IC to reset its reference points against the new cell's actual voltage profile. After that cycle, percentage readings stabilise.

Sudden shutdown at 20–30% on the replacement Ni-MH cell

Ni-MH cells have a steeper voltage cliff than Li-ion — voltage drops sharply once the cell passes a certain depletion threshold. The T200's low-battery cutoff is set at a fixed voltage point, and if the fuel gauge is still uncalibrated, it will read 20–30% remaining while the cell voltage has already crossed that cutoff threshold under load. The result is an abrupt shutdown with charge apparently still showing. Run one full calibration cycle and confirm the cell holds above 3.0V under the handset's active load before trusting the percentage display.