MTC Android Evo Replacement Battery 3.7V 700mAh Li-ion

MTC Android / Evo — 3.7V Li-ion Replacement Battery

This is a 3.7V, 700mAh (2.59Wh) Li-ion replacement cell for MTC Android and Evo smartphones. It fits devices that accept a 54.05 x 34.10 x 5.40mm cell with a standard Li-ion charge profile. Swap it in when the original cell no longer holds enough charge to get through normal daily use.

• Android and Evo compatibility: Both models share the same cell footprint, voltage rail, and connector pinout — one replacement cell covers either device without modification.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on compatible hardware. The BMS accepted the standard Li-ion charge profile, reached full charge without tripping protection, and held voltage within spec across the discharge curve.
• Fuel gauge recalibration on first cycle: On first use after installation, disable fast charging and run one full discharge-to-charge cycle. This lets the fuel gauge IC map its coulomb counter against the new cell's discharge curve before high-current charging begins on an uncalibrated cell.

Sudden shutdown at 20–30% on the replacement cell

This happens when the fuel gauge IC is still calibrated to the old cell's discharge curve. The new cell hits a voltage cliff under modem or screen load at a different state-of-charge than the IC expects. The phone interprets that voltage drop as a fault and shuts down before the percentage reaches zero. Run one full discharge cycle without interruption — let the phone drain until it shuts itself off, then charge uninterrupted to 100% — and the IC will recalibrate to the new curve.

Phone reporting wrong battery percentage after cell swap

The fuel gauge IC stores a learned discharge profile for the original cell. After a cell swap, the IC reads voltage against the old profile and reports an inaccurate state of charge — often jumping erratically or showing 100% until a sudden drop. One complete uninterrupted discharge-to-charge cycle resets the coulomb counter against the new cell. After that cycle, percentage readings stabilise. If the phone has a dedicated battery stats reset option in developer settings, run that before the calibration cycle.