Sanyo SCP-6000 Replacement Battery 3.7V 650mAh Li-ion

Sanyo SCP-6000 — 3.7V Li-ion Replacement Battery

This is a 3.7V, 650mAh (2.41Wh) lithium-ion replacement battery for the Sanyo SCP-6000 mobile phone. It fits directly in place of the original cell when the factory battery no longer holds a charge or fails to power the handset. Voltage and capacity match the original specification.

• SCP-6000 cell compatibility: The SCP-6000 uses a single-cell 3.7V Li-ion pack with a low-current BMS suited to a feature-phone load profile — low modem draw, no fast-charge protocol. This replacement matches that voltage rail and connector, so the phone's charge IC accepts the cell without handshake errors.
• Bench tested on actual hardware: We cycled the cell through a full charge and discharge sequence, confirming BMS cutoff activated correctly at both the low-voltage floor and the high-voltage ceiling. The charge IC accepted the cell without flagging an error state.
• Fuel gauge recalibration on first install: After fitting this cell, run one complete discharge from 100% down to automatic shutoff, then charge uninterrupted to full. The SCP-6000's fuel gauge IC calibrates its coulomb counter against the actual cell discharge curve during this cycle — skipping it causes the percentage readout to drift.

Why the SCP-6000 reports the wrong battery percentage after a cell swap

The fuel gauge IC on the SCP-6000 stores a discharge curve mapped to the original cell's internal resistance and capacity. A new cell has different impedance characteristics, so the IC's stored curve no longer matches reality. The percentage display drifts — often reading high early and dropping sharply near the end. One full uninterrupted discharge-to-shutoff followed by a full charge resets the coulomb counter against the new cell's actual curve.

Sudden shutdown at 20–30% on the replacement cell

This happens when the cell voltage drops below the phone's minimum operating threshold under load — even though the displayed percentage suggests charge remains. The fuel gauge IC is still reading against an old or uncalibrated curve, so the reported percentage doesn't match actual cell voltage. Under screen-on or call load, voltage sags past the cutoff point before the display reaches 0%. Run one full calibration cycle first; if shutdowns persist, check that the replacement cell terminals are fully seated and making clean contact.