About this replacement
Xplore G18 / G88 — 3.7V Li-Polymer Replacement Battery (BO81)
This is a 3.7V, 950mAh lithium-polymer cell for the Xplore G18 and G88 smartphones. It replaces OEM part numbers BO81 and A00097459. The battery powers the processor, display, and cellular radio stack in both handsets.
- G18 and G88 shared platform: Both models run the same 3.7V battery rail, use the same connector pinout, and expect the same BMS handshake. One cell fits both without modification.
- Bench tested on actual hardware: We cycled this cell through full charge and discharge on the G18. The BMS accepted the charge profile correctly, voltage held steady across the modem-active and display-on load states, and no over-voltage or under-voltage cutoff events were logged.
- Fuel gauge recalibration on first use: After installing this cell, disable fast charging and run one complete discharge-to-charge cycle before normal use. The G18 fuel gauge IC is calibrated to the old cell's discharge curve. Giving it one full cycle at standard charge current lets it remap the new cell's curve accurately before fast charging pushes higher current into an uncalibrated gauge.
Sudden shutdown at 20–30% on the Xplore G18 after cell replacement
This is a voltage-cliff failure. The fuel gauge IC still holds the old cell's discharge curve in memory, so the percentage it reports does not match where the new cell's voltage actually drops off. Under modem or screen load, the new cell hits its minimum cutoff voltage before the OS expects it to. The phone shuts down to protect the cell even though the screen showed charge remaining. One full discharge-charge cycle at standard rate forces the coulomb counter to relearn the new cell's curve, and the shutdowns stop.
Battery percentage jumping erratically in the first two days after installation
The G18's fuel gauge IC uses a coulomb counter that was calibrated against the worn original cell. A new 950mAh cell has a significantly different impedance and discharge curve, so the counter mismaps capacity at mid-range states of charge. Percentages can jump 10–15 points in either direction during normal use until the IC recalibrates. Run two full discharge-charge cycles at standard current — by the end of the second cycle, the counter has enough real data to track the new cell accurately and the erratic jumps settle out.