Meilan A5 BT710 Replacement Battery 3.8V 3000mAh

Meilan A5 — 3.8V Li-Polymer Replacement Battery (BT710)

This is a 3.8V, 3000mAh (11.4Wh) Li-Polymer cell for the Meilan A5 smartphone. It replaces OEM part number BT710 directly. If your A5 is shutting down unexpectedly, failing to hold charge, or not powering on at all, this cell addresses those degraded-cell symptoms.

• Meilan A5 fit: The A5 uses a specific connector pinout and physical envelope — 74.85 × 60.10 × 3.90mm — that matches BT710. The charge IC on the A5 mainboard expects a 3.8V nominal Li-Polymer cell; any deviation causes charge termination errors or incorrect state-of-charge readings.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the A5 platform. The BMS handshake completed without fault flags, charge current ramped correctly through CC-CV phases, and the fuel gauge IC accepted the new cell without throwing a calibration error on the first cycle.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging pushes current into an uncalibrated cell — preventing erratic percentage readings from the first hour.

Why the A5 reports wrong battery percentage after a cell swap

The A5 uses a coulomb counter that builds its state-of-charge model against the original cell's impedance and discharge curve. When a new cell goes in, that model is stale. The phone reads voltage and maps it to the old curve, so reported percentage drifts from actual charge state. One full slow discharge to automatic shutdown — followed by a full charge without interruption — resets the coulomb counter baseline and brings reported percentage back into sync.

Sudden shutdown at 20–30% on the replacement cell

This shutdown happens at a voltage cliff — typically around 3.5–3.6V under load — where the modem radio or screen backlight draws more current than the cell can sustain at that state of charge, causing a brief voltage dip below the BMS cutoff threshold. The phone interprets this as a dead cell and cuts power, even though the displayed percentage looks safe. It is more common on the first few cycles before the fuel gauge IC has recalibrated. Run two full discharge-charge cycles without fast charging; the cutoff threshold stabilises once the IC has an accurate discharge curve to work from.