About this replacement
O2 XDA Flame — 3.7V Li-ion Replacement Battery (XP-08)
This is a 3.7V, 2000mAh Li-ion cell that replaces the original battery in the O2 XDA Flame smartphone. It fits the XDA Flame directly and restores power to the device when the original cell can no longer hold a usable charge. Capacity is rated at 7.4Wh and matches the OEM specification for this handset.
- XDA Flame fit: The XDA Flame uses a dedicated battery bay sized for this cell format — 71.61 × 59.89 × 4.38mm — with a fixed connector layout. Any replacement must match that footprint exactly or the back cover will not seat flush and the connector will misalign.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the XDA Flame platform. The BMS accepted charge current without cutoff and held voltage above the device's shutdown threshold across a full discharge cycle.
- Fuel gauge recalibration after swap: On first use after installation, run one full discharge-charge cycle with fast charging disabled. This lets the fuel gauge IC on the XDA Flame map its coulomb counter against the new cell's actual discharge curve before normal charging resumes.
Sudden shutdown at 20–30% on the XDA Flame after a cell swap
The XDA Flame's fuel gauge IC was calibrated against the original cell's discharge curve. A new cell with a slightly different internal resistance profile will cause the gauge to misread remaining capacity. When the modem or screen draws a high current burst, the cell voltage drops below the hardware shutdown threshold — even though the gauge still shows 20–30%. This is a calibration gap, not a faulty cell. One full discharge to automatic shutdown, followed by an uninterrupted charge to 100%, resets the coulomb counter and narrows the gap.
XDA Flame not powering on after the battery sat discharged in storage
If a Li-ion cell drops below approximately 2.5V per cell, the BMS trips a deep-discharge lockout to prevent damage. The XDA Flame will show nothing on screen — no charge indicator, no boot logo. Connect the device to a wall charger rated for at least 1A output and leave it for 20–30 minutes without pressing any buttons. The BMS needs a low-current trickle to recover cell voltage above the lockout threshold before it will allow normal charge current to flow. Once the screen shows a charge icon, the BMS has re-initialised and the device will boot normally.