AK-V99 Emporia Select Replacement Battery 3.7V 1200mAh

Emporia Select / V99 / Basic V26 — 3.7V Li-ion Replacement Battery (AK-V99)

This is a 3.7V, 1200mAh Li-ion cell that replaces the original AK-V99 battery in the Emporia Select, V99, and Basic V26 mobile phones. It restores power to devices where the original cell has degraded, swollen, or failed to hold a charge. Capacity is 4.44Wh, matching the stock specification.

• Select, V99, and Basic V26 compatibility: These three models share the same battery bay dimensions, connector pinout, and BMS handshake protocol. The AK-V99 cell fits all three without modification — the 58.24 x 43.20 x 5.05mm footprint is consistent across the lineup.
• Bench tested on actual hardware: We ran this cell through full charge-discharge cycles on a V99 unit. The BMS accepted the cell without fault codes, charge current tapered correctly at 4.2V, and the protection circuit triggered cleanly at the low-voltage cutoff threshold.
• Fuel gauge recalibration after install: On the Emporia Select, the fuel gauge IC retains the discharge curve from the old cell. After fitting this replacement, disable fast charging and run one complete discharge-charge cycle from 100% to near-empty and back. This lets the IC recalibrate against the new cell's actual curve before resuming normal use.

Why the Emporia Select reports wrong battery percentage after a cell swap

The Select uses a fuel gauge IC that builds a discharge model based on the old cell's internal resistance and capacity curve. When a new cell goes in, that stored model no longer matches reality. The IC will report inflated percentages early in discharge and then drop sharply near the end. One full discharge-charge cycle — letting the phone run down to automatic shutdown and then charging uninterrupted to 100% — forces the coulomb counter to reset and relearn the new curve.

Sudden shutdown at 20–30% on the replacement cell

This happens when the fuel gauge IC has not yet recalibrated and the phone hits a voltage cliff under modem or screen load. The cell voltage drops below the shutdown threshold before the displayed percentage reaches zero. It is not a faulty cell — it is a calibration gap. Run one full uninterrupted discharge cycle, then recharge to 100% without interruption. After that cycle, the reported percentage and actual cell voltage should track correctly.