AK-S2 Emporia Smart 2 Compatible Battery 3.8V 2400mAh

Emporia Smart 2 — 3.8V Li-Polymer Replacement Battery (AK-S2)

This 3.8V, 2400mAh Li-Polymer cell replaces the original AK-S2 battery in the Emporia Smart 2 smartphone. It restores power to a phone that won't hold charge or shuts down unexpectedly. Voltage and capacity match the original spec exactly.

• Emporia Smart 2 fitment: The Smart 2 uses a specific connector pinout and BMS handshake tied to the AK-S2 part number. This cell carries the matching contact layout and charge profile so the phone's charge IC accepts it without throwing a protection fault.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the Smart 2 platform. The BMS accepted the charge profile on the first cycle, protection cutoffs triggered correctly at both ends of the voltage window, and no thermal events were recorded.
• 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 register — preventing false percentage readings from the start.

Sudden shutdown at 20–30% on the replacement cell

This happens when the fuel gauge IC is still calibrated to the old cell's discharge curve. A fresh Li-Polymer cell has a steeper voltage cliff under load — the modem or screen draws current, voltage dips sharply, and the phone interprets it as an empty battery. The fix is one full uninterrupted discharge to automatic shutdown, followed by a full charge without interruption. After that cycle, the coulomb counter resets against the actual cell curve and the shutdowns stop.

OS reporting wrong battery percentage after cell swap

The Smart 2's fuel gauge IC stores the charge curve of the previous cell in memory. When a new cell goes in, the IC continues reading against old data — so 40% on screen may mean 15% actual charge remaining. This is not a fault with the replacement cell. Run the phone down to automatic shutdown once, then charge uninterrupted to 100%. That single full cycle overwrites the stored curve and brings the percentage display back in line with real capacity.