Aligator A300 Compatible Battery 3.7V 1050mAh

Aligator A300 — 3.7V Li-ion Replacement Battery

This is a 3.7V, 1050mAh Li-ion cell for the Aligator A300 basic mobile phone. It replaces the original battery when capacity has faded to the point where the phone shuts down early or won't hold a usable charge. Dimensions are 55.42 × 35.01 × 5.41mm — measure your existing cell before ordering if you are unsure.

• A300 cell compatibility: The A300 runs a low-draw circuit with a simple charge IC. This cell matches the original 3.7V nominal voltage rail and physical footprint, so the battery connector seats without force and the charge IC sees the correct cell impedance on first contact.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a A300-class load profile. The BMS held cutoff correctly at the low-voltage threshold and did not trip during screen-on or call modem bursts.
• Fuel gauge recalibration on first install: On first use after installation, disable any fast-charge mode and run one full discharge-to-charge cycle before normal use. This lets the phone's fuel gauge IC map the new cell's discharge curve accurately — skipping this step causes the percentage counter to jump or read incorrectly for several days.

Why the A300 reports wrong battery percentage after a cell swap

The A300's fuel gauge IC stores a learned discharge curve from the original cell. When a new cell goes in, that stored curve no longer matches the new cell's actual voltage-to-capacity profile. The IC keeps reading percentage against old data, so the display shows incorrect numbers. One full discharge cycle — from 100% to automatic shutdown — forces the IC to rewrite its calibration table against the new cell.

Sudden shutdown at 20–30% on the A300 after replacement

This usually means the fuel gauge IC has not yet recalibrated to the new cell's voltage cliff. Li-ion cells drop voltage sharply below a certain state of charge, and the A300's modem load can pull the cell voltage below the BMS cutoff threshold faster than the display percentage suggests. The phone cuts power before the reported percentage reaches zero. Run two full discharge-charge cycles and the shutdowns typically stop — the IC recalibrates its low-voltage warning point to match the new cell curve.