BL-166 GSmart Maya M1 Replacement Battery 3.7V 1700mAh

GSmart Maya M1 / Maya M1 V2 / i350 — 3.7V Li-ion Replacement Battery (BL-166)

This is a 3.7V 1700mAh (6.29Wh) Li-ion cell that replaces the original BL-166 battery in the GSmart Maya M1, Maya M1 V2, and i350 smartphones. It fits the same slot, uses the same connector, and communicates with the same charge IC. When the original cell degrades and the phone starts shutting down unexpectedly or holding charge poorly, this is the direct swap.

• Maya M1 / Maya M1 V2 / i350 fit: All three models share the BL-166 form factor — same 66.50 × 55.82 × 4.80mm footprint, same three-pad connector layout, and the same BMS handshake with the charge IC. No adapter or modification needed.
• Bench tested on actual hardware: We cycled the cell through charge and discharge under modem and screen load. The BMS held the 4.2V charge ceiling correctly and triggered the low-voltage cutoff at the expected floor — no premature trips, no false full-charge flags.
• Fuel gauge recalibration on first use: Disable any fast-charge mode for the first complete discharge-to-charge cycle after installation. This gives the fuel gauge IC one clean pass to map the new cell's discharge curve before high-current charging runs against an uncalibrated table.

Why the Maya M1 reports wrong battery percentage after a cell swap

The Maya M1 uses a fuel gauge IC that tracks charge state using a coulomb counter calibrated to the original cell's discharge curve. When a new cell goes in, the stored curve no longer matches actual cell behaviour. The percentage the OS displays is calculated against stale data. One full discharge from 100% down to automatic shutdown, followed by a full charge, resets the coulomb counter to the new cell and corrects the readout.

Sudden shutdown at 20–30% on the replacement cell

This happens when the cell voltage drops sharply under combined modem and display load — the screen-on and LTE radio together pull enough current to push the cell below the BMS cutoff threshold even though the fuel gauge still shows charge remaining. It is more common in the first few cycles before the fuel gauge recalibrates. Run two full discharge-charge cycles without fast charge. If the shutdowns persist past cycle three, check that the connector contacts are fully seated — a loose pad adds resistance and worsens voltage sag under load, dropping the cell toward the 3.0V cutoff faster than the gauge expects.