Socketmobile Sonim XP7 Replacement Battery BAT-04800-01S 3.8V 4700mAh

Socketmobile Sonim XP7 Series — 3.8V Li-ion Replacement Battery (BAT-04800-01S)

This 3.8V Li-ion battery at 4700mAh replaces part BAT-04800-01S in the Sonim XP7 and XP7700 rugged smartphones. It also fits the Sonim XP6 and XP6700. All four models share the same battery bay dimensions and BMS handshake protocol.

• XP6 and XP7 platform compatibility: Sonim built the XP6 and XP7 lines on the same physical battery form factor — 63.60 x 44.10 x 12.10mm — with matching connector pinouts and the same BMS communication protocol. One cell fits all four models without modification.
• Bench tested on actual hardware: We ran this cell through a full charge and discharge cycle on the XP7700. The BMS accepted the cell on first insertion, reported state-of-charge correctly after calibration, and thermal readings stayed within normal bounds throughout the charge cycle.
• Fuel gauge recalibration on first use: After installation, disable fast charging and run one full discharge-charge cycle at standard rate. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging begins on an uncalibrated cell.

Sudden shutdown at 20–30% on the XP7 after a cell swap

The Sonim XP7 runs a push-to-talk radio stack and LTE modem simultaneously under load. That combination pulls high current spikes. A fresh replacement cell with an uncalibrated fuel gauge IC can report 25% remaining while actual cell voltage drops below the BMS cutoff threshold under that load — triggering an abrupt shutdown. The fix is to complete one full uninterrupted discharge to below 5% and then a full charge to 100%. After that single cycle, the coulomb counter has enough data to track real cell capacity accurately.

USB fast charge not activating on first cycle after replacement

On first insertion, the BMS in the replacement cell has not yet completed handshake verification with the phone's charge IC. The XP7's charging controller defaults to standard 5V/1A input until it confirms BMS compatibility — fast charge protocols stay locked out for the first cycle. This is normal behaviour, not a fault. Complete one full charge at standard rate, then reconnect the fast charger — the handshake completes and high-current charging activates from the second cycle onward.