Aligator A800BAL Replacement Battery 3.7V 1700mAh

Aligator A800 / A850 Series — 3.7V Li-ion Replacement Battery (A800BAL)

This is a 3.7V, 1700mAh Li-ion cell built to fit the Aligator A800, A850, A800 Senior, and AZ01302 smartphones. It replaces the original A800BAL pack when capacity has dropped or the cell no longer holds a charge. Voltage and connector match the OEM spec — no modifications needed.

• A800 / A850 platform fit: These models share the same battery bay dimensions, connector pinout, and BMS handshake protocol. A single cell — 66.20 × 44.00 × 5.10mm — covers the entire family without adapter changes or wiring modifications.
• Bench tested on actual hardware: We cycled this cell through full charge and discharge passes on the A800 platform. The BMS accepted the charge handshake on the first connection, held voltage above the modem-load threshold, and triggered protection cutoff correctly at the low-voltage limit.
• First-cycle calibration on the A800 Senior: On first use after installation, disable fast charging and run one complete discharge-charge cycle at standard rate. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging pushes current into an uncalibrated state — particularly important on the A800 Senior, which uses a simplified charge UI that hides calibration warnings.

Sudden shutdown at 20–30% on the A800 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 that the gauge didn't predict, so the phone cuts power before the displayed percentage reaches zero. The fix is a full uninterrupted discharge-charge cycle with the screen kept active — this forces the coulomb counter to reset its endpoint reference. After one full cycle, shutdowns at 20–30% stop in most cases.

Phone won't power on after the replacement cell sat in storage

Li-ion cells self-discharge during storage. If the voltage drops below approximately 2.5V per cell, the BMS enters lockout mode and blocks all charge input as a safety measure. The phone appears completely dead — no charge indicator, no vibration on cable connection. Connect to a wall adapter rated at 5V/1A or higher and leave it for 15–20 minutes without pressing the power button. The BMS needs sustained trickle current to exit lockout before the phone will respond.