Vodafone Li3706T42P3h413457 Compatible Battery 3.7V 650mAh

Vodafone Li3706T42P3h413457 — 3.7V Li-ion Replacement Battery

This is a 3.7V, 650mAh (2.41Wh) lithium-ion replacement battery for compatible Vodafone smartphones that carry OEM part number Li3706T42P3h413457. It covers phones that have stopped holding charge or fail to power on due to a degraded original cell. Check your existing battery for the part number printed on the label before ordering.

• Li3706T42P3h413457 cell platform: Vodafone smartphones on this battery share a 3.7V nominal rail with a matched connector footprint and BMS communication protocol. The fuel gauge IC on the motherboard reads cell state-of-charge data directly from this pack — swapping a cell outside this spec causes the gauge to misread from the first cycle.
• Bench tested on actual hardware: We cycled this cell through charge and discharge using a calibrated load. The BMS held cutoff voltage correctly at the low end and did not trip prematurely during mid-cycle current draw. Charge termination voltage reached 4.2V as expected.
• First-cycle fuel gauge reset: After fitting this battery, disable fast charging and run one full discharge-to-charge cycle at standard rate. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging pushes current into an uncalibrated state — otherwise the percentage readout drifts from the first hour of use.

Why the phone reports the wrong battery percentage after fitting this cell

The fuel gauge IC on the motherboard builds a discharge model from the previous cell over hundreds of cycles. When a new cell goes in, that model no longer matches the actual chemistry. The gauge reads voltage and estimates capacity against an outdated curve, so it can show 80% when the cell is closer to 50%. One full discharge below 10% followed by a full charge to 100% at standard rate forces the coulomb counter to reset against the new cell's actual curve. After that cycle, the percentage readout tracks accurately.

Sudden shutdown at 20–30% remaining on the new battery

This happens when the cell voltage drops below the modem's or display's minimum operating threshold before the gauge reaches 0%. Under load — an active call, GPS, or full-brightness screen — current draw spikes and the cell voltage sags sharply. If the BMS sees voltage fall below roughly 3.0V under that load, it cuts out to protect the cell, even if the gauge still shows charge remaining. The fix is to complete the first-cycle calibration run described above so the fuel gauge IC learns where the actual voltage cliff sits on this specific cell.