Gionee M7 BL-N4000E Replacement Battery 3.85V 4000mAh

GIONEE M7 / M7L — 3.85V Li-Polymer Replacement Battery (BL-N4000E)

This is a 4000mAh, 3.85V lithium-polymer cell replacing the OEM BL-N4000E in the GIONEE M7 and M7L smartphones. It matches the original cell's physical footprint at 85.60 × 63.96 × 3.92mm, so it seats correctly in the battery bay without modification. Voltage and capacity figures come from product data, not estimated equivalents.

• M7 and M7L compatibility: Both models share the same battery bay dimensions, connector pinout, and BMS communication protocol. The BL-N4000E part number covers both variants — the handsets use the same charge IC and fuel gauge configuration, so one cell fits both without any adaptation.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the M7 platform and confirmed the BMS handshake completed correctly. The charge IC accepted the cell without triggering a fault state, and the protection circuit responded normally to load spikes from the modem and display.
• Fuel gauge recalibration after installation: On first use after fitting this cell, disable fast charging and run one full discharge-charge cycle at standard rate. The fuel gauge IC in the M7 is calibrated to the old cell's discharge curve — a full cycle at slow current lets it remap the new cell's voltage-to-capacity profile before high-current charging is applied to an uncalibrated cell.

Sudden shutdown at 20–30% on the GIONEE M7 after a cell swap

This is a voltage cliff issue, not a capacity defect. The M7's fuel gauge IC still holds the old cell's discharge curve in memory, so it miscalculates the remaining charge as the new cell approaches lower state-of-charge. Under modem or screen load, the cell voltage drops faster than the gauge expects, and the phone cuts power to protect the circuit before the percentage reaches zero. One complete discharge to 0% followed by a full uninterrupted charge resets the coulomb counter and resolves the premature cutoff.

USB fast charge not activating on the M7 after battery replacement

A new high-impedance cell can cause the charge IC to default to a trickle or standard charge rate on the first cycle. The fast charge handshake requires the BMS to confirm cell status before the IC ramps current — on a fresh cell this confirmation can take one full charge cycle to complete. If fast charging does not activate after the first cycle, check that the cable and adapter are the same ones that worked with the original battery. If a second standard-rate charge cycle completes and fast charge still does not engage, verify the adapter output voltage matches the M7's fast charge input requirement of 9V.