Motorola V690 Replacement Battery 3.7V 650mAh Li-ion

Motorola V690 — 3.7V Li-ion Replacement Battery

This 3.7V, 650mAh lithium-ion cell replaces the original battery in the Motorola V690 flip phone. It fits the V690 directly and restores normal operation for calls, messaging, and basic phone functions. Voltage and capacity match the stock specification — 3.7V nominal, 2.41Wh total energy.

• V690 compatibility: The V690 uses a compact lithium-ion cell at 3.7V nominal. This replacement matches that voltage rail and physical form factor. No modifications are needed to the battery bay or connector.
• Bench tested on actual hardware: We cycled this cell through a full discharge and charge sequence on the V690 platform. The BMS accepted the cell, charge termination triggered correctly at 4.2V, and the phone registered the battery without error flags.
• Fuel gauge recalibration on first use: After fitting this cell, disable fast charging if the option exists, then run one complete discharge down to automatic shutoff followed by a full charge. This gives the phone's fuel gauge IC a reference curve for the new cell before it starts calculating state-of-charge under load.

Why the V690 reports wrong battery percentage after a cell swap

The V690's fuel gauge IC builds its state-of-charge estimate from the discharge curve of the original cell. A new cell has a slightly different internal resistance and discharge profile. Until the IC recalibrates, it maps voltage readings against the old curve and returns inaccurate percentages. One full discharge-to-shutoff cycle followed by a complete charge resets the reference and brings the readout back in line.

Sudden shutdown at 20–30% remaining on the new cell

This happens when the cell voltage drops sharply under load — typically during a call when the radio draws a burst of current the gauge didn't anticipate. The phone's protection circuit reads a voltage dip below its cutoff threshold and shuts down, even though the display showed charge remaining. The fuel gauge was still running off the old cell's curve. Run one full calibration cycle first; if the shutoffs continue, check that resting cell voltage measures above 3.6V before the next use.