About this replacement
Pantech Marauder / Star Q / ADR910L — 3.7V Li-ion Replacement Battery (BTR910B)
This is a 3.7V 1400mAh Li-ion cell that replaces the BTR910B in the Pantech Marauder, Star Q, ADR910L, and ADR910LVW. It restores power to phones where the original cell has degraded, swollen, or stopped holding charge. Voltage and physical dimensions match the original: 59.20 × 46.90 × 5.60mm.
- Marauder / Star Q platform fit: These models share the same battery bay dimensions, connector pinout, and BMS handshake protocol — one cell covers the full ADR910L line without modification.
- Bench tested on actual hardware: We cycled this cell through charge and full-draw discharge on the ADR910L platform. The BMS accepted charge without fault codes and held the voltage curve across the full discharge range.
- Fuel gauge recalibration on first use: On first use after installation, run one full discharge-charge cycle before enabling any fast-charge mode. This lets the fuel gauge IC map the new cell's discharge curve — without it, the OS may read percentage against the old cell's profile and report inaccurate figures.
Why the Marauder reports wrong battery percentage after a cell swap
The ADR910L uses a fuel gauge IC that builds a discharge model from accumulated cycle data on the old cell. When you install a new cell, that stored model no longer matches the actual discharge curve. The phone interpolates percentage from a mismatched reference, so the number on screen drifts — often reading higher than actual charge. One complete discharge to shutdown followed by a full charge resets the coulomb counter and forces a fresh calibration pass. After that cycle, percentage accuracy typically stabilises.
Sudden shutdown at 20–30% remaining on the replacement cell
This happens when the fuel gauge IC is still calibrated to the old cell's voltage curve. The new cell hits a voltage cliff under load — modem transmit or screen refresh pulls enough current to drop cell voltage below the BMS cutoff threshold before the display percentage catches up. The phone reads 25% and then cuts out instantly. Run the full recalibration cycle described above and check that cell voltage at shutdown was around 3.4–3.5V — if it is, the BMS is working correctly and the gauge just needed realignment.