WINNER WG11 Replacement Battery 3.7V 1300mAh Li-ion

WINNER WG11 / WG12 — 3.7V Li-ion Replacement Battery

This is a 3.7V 1300mAh Li-ion cell for the WINNER WG11 and WG12 smartphones. It replaces the original battery when the cell has degraded past the point of holding a usable charge. Dimensions are 60.00 × 43.80 × 4.50mm — confirm these against your existing battery before ordering.

• WG11 and WG12 compatibility: Both models share the same battery bay dimensions, voltage rail, and connector layout, so one cell fits both. The BMS protection circuitry matches the charge IC in each device.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the bench. The BMS triggered overcurrent protection correctly and the cell held voltage within spec across the full discharge curve.
• First-cycle fast charge tip: 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 replacement cell

The fuel gauge IC in the WG11 was calibrated to the discharge curve of the original cell. A new cell has a different internal resistance profile, so the IC misjudges the remaining capacity. Under load — screen brightness, mobile data, or GPS — the cell voltage drops faster than the gauge expects, triggering a low-voltage shutdown even though the reported percentage looks safe. One full discharge to near-zero followed by a complete charge resets the coulomb counter and brings percentage reporting back into alignment.

Phone warm near the battery on the first few charges

A fresh cell starts with higher internal impedance than a conditioned one. The charge IC pushes current into that impedance, and the energy lost appears as heat. This is normal for the first two to three cycles as the cell's internal resistance settles. If the device stays warm past three full cycles, check that the charge port and cable are clean and that no third-party fast-charge adapter is overriding the charge IC's current limit.