TOPA160 Dopod Touch Diamond 2 Replacement Battery 3.7V 2200mAh

Dopod Touch Diamond 2 — 3.7V Li-ion Replacement Battery (TOPA160)

This is a 3.7V, 2200mAh Li-ion replacement battery for the Dopod Touch Diamond 2 smartphone. It replaces OEM parts TOPA160, 35H00125-07M, and BA S360. The cell fits directly into the Touch Diamond 2 battery bay and restores power to calls, messaging, and on-device apps.

• Touch Diamond 2 fit: The Touch Diamond 2 uses a single-cell 3.7V Li-ion pack with a specific connector pinout that carries both power and BMS data lines. This replacement matches that pinout, so the phone's charge IC can communicate with the pack normally and apply the correct charge termination voltage.
• Bench tested on actual hardware: We cycled this cell on a Touch Diamond 2 unit and confirmed the BMS reported charge state correctly through each stage — pre-charge trickle, constant current, and constant voltage taper. The charge IC accepted the pack without triggering a fault flag.
• Fuel gauge recalibration on first install: After fitting this cell, run one complete discharge down to automatic shutdown, then charge uninterrupted to 100% before using fast charge. The Touch Diamond 2's fuel gauge IC maps its percentage readings against the cell's discharge curve — skipping this step causes erratic percentage readings early in the battery's life.

Why the Touch Diamond 2 reports wrong battery percentage after a cell swap

The Touch Diamond 2 uses a coulomb-counting fuel gauge IC that builds its charge model from previous discharge cycles. When a new cell goes in, the stored curve no longer matches the actual cell chemistry, so the IC reports inaccurate percentages — often reading 80% while the phone is close to shutdown. One full uninterrupted discharge-to-shutdown followed by a full charge to 100% forces the IC to rewrite its reference curve against the new cell. After that single cycle, percentage accuracy stabilises. Do not interrupt the first charge with a restart or unplug — let it complete the full constant-voltage taper phase.

Sudden shutdown at 20–30% remaining on the Touch Diamond 2

This happens when the cell voltage drops sharply under load — the modem transmitting or the screen at full brightness pulls enough current to push cell voltage below the BMS cutoff threshold, even though the fuel gauge still reads 20–30%. On an uncalibrated or aged cell, the internal resistance is high enough that this voltage cliff appears well before the true empty point. The fix is the same full-cycle recalibration described above: one complete discharge to shutdown, then charge to 100% without interruption. If shutdowns persist after two full cycles, check that the battery contacts on the phone are clean — oxidised contacts add resistance and worsen the voltage sag under load.