About this replacement
DOOV IEva D2 / D200T / D210T — 3.7V Li-ion Replacement Battery (BL-G29)
This is a 3.7V, 1650mAh Li-ion replacement cell for the DOOV IEva D2, D200T, and D210T smartphones. It replaces OEM part number BL-G29 directly. Swap it in when the original cell no longer holds a charge or the phone shuts down unexpectedly under load.
- IEva D2, D200T, and D210T compatibility: All three models share the same battery bay dimensions, 3.7V nominal rail, and BL-G29 connector pinout. The BMS handshake on each variant expects the same charge termination voltage, so one cell covers the full range without hardware changes.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the IEva D2 platform. The BMS accepted the cell on first connection, charge termination triggered correctly at 4.2V, and the protection circuit tripped as expected on an over-discharge stress test.
- Fuel gauge recalibration on first use: On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging pushes current into an uncalibrated state — preventing erratic percentage readings from the first week onward.
Why the IEva D2 reports wrong battery percentage after a cell swap
The fuel gauge IC on the IEva D2 uses a coulomb counter calibrated to the original cell's discharge curve. When a new cell goes in, the stored curve no longer matches the actual cell behaviour, so the reported percentage drifts — often reading 20–30% higher than actual state of charge. Running one full discharge down to automatic shutdown and then charging uninterrupted to 100% forces the IC to reset its reference points. After that single cycle, percentage accuracy stabilises significantly.
Sudden shutdown at 20–30% remaining on the replacement cell
This is a voltage cliff issue, not a capacity problem. Under modem transmission or screen brightness spikes, the cell's internal resistance causes a sharp voltage sag that drops below the BMS cutoff threshold — even when the coulomb counter still shows charge remaining. On a fresh cell, this happens most often before the first full calibration cycle is complete. Run one full discharge-to-shutdown and full recharge cycle; if shutdowns continue after that, check that the connector is fully seated and that no gold contact pins are bent, as a resistive connection amplifies the voltage sag at high-draw moments.