GSmart Mika MX Replacement Battery 3.8V 3000mAh Li-Polymer

GSmart Mika MX — 3.8V Li-Polymer Replacement Battery (Mika MX)

This 3.8V, 3000mAh (11.4Wh) lithium-polymer cell is a direct replacement for the GSmart Mika MX and Mika MX Dual SIM LTE smartphones. It fits when the original cell has degraded to the point of poor retention, unexpected shutdowns, or failure to hold charge under normal use. Dimensions are 77.30 × 58.90 × 5.00mm — verify against your existing cell before installation.

• Mika MX and Mika MX Dual SIM LTE coverage: Both variants share the same battery bay dimensions and connector pinout, so one cell serves either configuration without modification to the connector or seating tab.
• Bench tested on actual hardware: We cycled this cell through full charge and discharge on the Mika MX platform. The BMS accepted charge without fault codes, and the protection circuit tripped correctly at the low-voltage threshold — no unexpected cutoffs during the load phase.
• First-cycle fast charge protocol: On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC recalibrate against the new cell's discharge curve before high current is applied to an uncalibrated cell.

Sudden shutdown at 20–30% on the replacement cell

A new lithium-polymer cell has a steeper voltage cliff than a worn cell the fuel gauge IC was originally calibrated against. When the modem fires or the screen brightness spikes, instantaneous current draw pulls the cell voltage below the BMS cutoff threshold — even though the gauge still reads 20–30%. The fix is one full discharge-to-shutdown followed by an uninterrupted charge to 100%, repeated twice. After two full cycles, the coulomb counter has enough data to map the new cell's curve accurately, and the early shutdowns stop.

OS reporting wrong battery percentage after cell swap

The fuel gauge IC stores a learned discharge model from the previous cell. After swapping to a fresh 3000mAh cell, the stored model no longer matches, so the percentage readout jumps erratically or reads full when the cell is not. A calibration cycle resolves this: drain the phone until it powers off, then charge continuously to 100% without interruption. Do not unplug during the charge phase — partial cycles delay recalibration and extend the period of inaccurate readings.