Sprint PPC-6800 Replacement Battery 3.7V 2600mAh 35H00077-00M

Sprint PPC-6800 — 3.7V Li-ion 2600mAh Replacement Battery (35H00077-00M)

This 3.7V, 2600mAh lithium-ion battery replaces the original cell in the Sprint PPC-6800 Windows Mobile smartphone. It fits the PPC-6800 directly, restoring power to a device where the stock battery no longer holds a usable charge. Capacity is 9.62Wh — matching the original energy spec for this handset.

• PPC-6800 cell compatibility: The PPC-6800 uses a single-cell 3.7V nominal pack with a basic protection circuit. This replacement matches the voltage rail and connector footprint. OEM part numbers 35H00077-00M, 35H00077-02M, and TRIN160 all cross-reference to this cell configuration.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the PPC-6800 platform. The BMS protection circuit engaged correctly at low-voltage cutoff, and charge termination fired at the expected 4.2V ceiling without overrun.
• Fuel gauge recalibration on first use: After installing this cell, run one full uninterrupted discharge down to automatic shutdown, then charge to 100% without interruption. The PPC-6800 fuel gauge IC reads against a stored discharge curve — skipping this step leaves it calibrated to the old degraded cell, which causes erratic percentage readings from the first hour.

Why the PPC-6800 reports wrong battery percentage after a cell swap

The PPC-6800 uses a coulomb-counting fuel gauge IC that builds its percentage model from the discharge curve of whichever cell it last tracked. When the original degraded cell is removed and a fresh 2600mAh cell goes in, the IC still references the old curve — which has a much steeper voltage drop at low charge states. That mismatch makes the new cell appear to drain faster than it is, and the percentage readout jumps or stalls. One complete discharge-to-shutdown followed by a full uninterrupted charge resets the reference curve to the new cell. After that single cycle, percentage reporting stabilises.

Sudden shutdown at 20–30% on the replacement cell

This happens when the screen backlight, radio, or a running application pulls a current spike that the cell cannot sustain while the fuel gauge still shows significant charge remaining. The voltage drops sharply under load — hitting the protection circuit's cutoff threshold even though the state-of-charge estimate reads higher. It is a voltage cliff caused by the fuel gauge IC being uncalibrated to the new cell, not a defective battery. Run the full recalibration cycle described above — one complete discharge to auto-shutdown, then charge to 4.2V — and the shutdowns stop.