AudioVox PPC-4100 Replacement Battery BTR-4100 3.7V 1500mAh

AudioVox PPC-4100 — 3.7V Li-ion Replacement Battery (BTR-4100)

This is a 3.7V, 1500mAh Li-ion replacement battery for the AudioVox PPC-4100 Windows Mobile pocket PC smartphone. It replaces OEM part BTR-4100 directly. Fits the PPC-4100 only — confirm your model before ordering.

• PPC-4100 cell compatibility: The PPC-4100 uses a single-cell Li-ion pack running a 3.7V nominal rail. The device BMS expects a cell matched to that rail and the original connector pinout. This replacement matches both the voltage and the physical contact layout required for the charge IC to communicate correctly.
• Bench tested on actual hardware: We ran this cell through the PPC-4100 charge IC handshake, confirmed the BMS accepted the connection, and verified charge termination fired correctly at full capacity. No false cutoff events were observed during the test cycle.
• Fuel gauge recalibration on first cycle: On first use after installation, run one complete discharge-to-charge cycle before relying on the percentage readout. The fuel gauge IC in the PPC-4100 is calibrated against the old cell's discharge curve — a full cycle lets it map the new cell accurately before you trust its numbers.

Why the PPC-4100 reports wrong battery percentage after a cell swap

The PPC-4100 uses a fuel gauge IC that tracks charge by mapping voltage against a stored discharge curve from the original cell. When a new cell goes in, that stored curve no longer matches the new cell's voltage-to-capacity relationship. The IC reads voltage correctly but converts it to a percentage using the wrong reference, so you see jumps, stalls, or early full readings. One complete discharge and recharge cycle forces the IC to relearn the new curve and restores accurate reporting.

Sudden shutdown at 20–30% on the PPC-4100

This happens when the cell voltage drops sharply under load — screen backlight, radio, or processor activity pulls more current than the resting voltage suggests remains. The cell hits the BMS cutoff floor before the fuel gauge percentage reaches zero. The gauge was reading a resting voltage, not a load voltage, so the shutdown looks premature. After the replacement cell beds in over two or three full cycles, the load voltage holds more steadily and the shutdowns stop. If they persist, check that the cell is seated flat with no connector pin bent — a loose contact raises impedance and worsens voltage sag under load.