Vodafone WIZA16 VPA Compact II Replacement Battery 3.7V 2350mAh

Vodafone VPA Compact II — 3.7V Li-ion Replacement Battery (WIZA16)

This is a 3.7V, 2350mAh Li-ion cell that replaces the WIZA16 battery in the Vodafone VPA Compact II smartphone. It fits the original battery bay directly and connects to the same charge IC and fuel gauge circuitry. Use this when the original cell no longer holds adequate charge or the phone shuts down unexpectedly under load.

• VPA Compact II platform fit: The VPA Compact II uses a single-cell 3.7V Li-ion architecture with a hardwired connector tied to the onboard charge IC. This cell matches that voltage rail and connector pinout, so the BMS handshake completes without errors on boot.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the VPA Compact II platform. The BMS accepted the cell on first connect, charge termination triggered correctly at full voltage, and no protection cutoff events fired during load testing.
• Fuel gauge recalibration on first cycle: After fitting this cell, disable any fast-charge mode and run one full discharge-to-charge cycle before normal use. The fuel gauge IC on the VPA Compact II calibrates its coulomb counter against the cell's discharge curve — skipping this step causes the percentage display to read inaccurately for the first several cycles.

Sudden shutdown at 20–30% on the replacement cell

The VPA Compact II's fuel gauge IC stores a discharge curve from the original cell. When a new cell goes in, that stored curve no longer matches the actual voltage drop profile of the replacement. Under modem or screen load, the new cell's voltage dips faster than the IC predicts, crossing the hardware cutoff threshold before the percentage display reaches zero. The phone shuts off to protect the cell even though the reported percentage looks safe. One complete discharge-charge cycle forces the coulomb counter to relearn the new cell's curve. After that cycle, shutdowns at 20–30% stop.

Phone warm near the battery during the first few charges

A new Li-ion cell has higher internal impedance than a conditioned one. During the first charge cycles, the charge IC pushes current into that higher-impedance cell, and more energy converts to heat than it will once the cell is broken in. This is normal and resolves after three to five full charge cycles as impedance drops. If the phone stays warm beyond the fifth charge or feels hot rather than warm, stop charging and check the USB connection for debris causing partial contact and elevated resistance.