LG VS910 Replacement Battery 3.7V 1500mAh BF-45FNV

LG VS910 Revolution 4G — 3.7V Li-ion Replacement Battery (BF-45FNV)

This 3.7V 1500mAh Li-ion cell replaces the original battery in the LG VS910, Revolution, Revolution 4G, and MS910. It fits the original battery bay with no modification. Swap it in when the existing cell no longer holds charge or triggers unexpected shutdowns.

• VS910 / Revolution 4G platform fit: These models share the same 3.7V single-cell architecture, battery connector pinout, and BMS communication protocol — one cell covers all variants in the lineup without any wiring or bracket changes.
• Bench tested on actual hardware: We cycled this cell through charge and load on a VS910 unit. The BMS accepted the cell on first insertion, charge termination triggered correctly at 4.2V, and the protection circuit tripped as expected under a simulated dead-short condition.
• Fuel gauge recalibration on first use: After installing this cell, run one full discharge-charge cycle with fast charging disabled. The fuel gauge IC on the VS910 was calibrated to the old cell's discharge curve — running one unconstrained cycle lets the coulomb counter reset its reference before high-current charging begins.

Sudden shutdown at 20–30% on the VS910 after a cell swap

The VS910 fuel gauge IC tracks battery state using a coulomb counter referenced to the original cell's voltage-capacity curve. A new cell has a slightly different internal resistance profile, so the gauge loses accuracy near the bottom of the discharge range. Under LTE radio load or screen-on bursts, the cell voltage drops faster than the gauge expects and the BMS cuts power before the OS can record it as a low-battery shutdown. One full discharge-charge cycle recalibrates the counter. After that cycle, the reported percentage tracks actual cell voltage within normal tolerance.

Phone shows incorrect battery percentage for several days after replacement

The VS910's fuel gauge IC stores a learned discharge model tied to the old cell's impedance. When a new cell goes in, that stored model is wrong — the gauge may read 80% while the cell is nearly empty, or jump erratically between readings. This is a calibration gap, not a faulty cell. Drain the battery until the phone shuts off from low voltage, then charge to 100% without interruption. After one complete cycle, the coulomb counter rebuilds its reference and percentage reporting stabilises.