LG Transpyre BL-41A1H Replacement Battery 3.7V 1600mAh

LG Transpyre / VS810 — 3.7V Li-ion Replacement Battery (BL-41A1H)

This is a 3.7V, 1600mAh Li-ion cell built to the BL-41A1H spec for the LG Transpyre, VS810, VS810PP, and LS660. It replaces the original cell when capacity has dropped or the battery no longer holds a usable charge. Voltage and physical footprint match the OEM unit at 76.14 × 47.77 × 4.22mm.

• Transpyre / VS810 platform fit: The VS810, VS810PP, and LS660 all share the same battery bay geometry and BMS handshake protocol. One cell covers all variants without modification.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a VS810 unit. The BMS accepted charge from the first connection, current tapered correctly at full voltage, and no cutoff errors were logged.
• Fuel gauge recalibration on first use: After fitting this cell, disable fast charging and run one complete discharge-to-charge cycle before normal use. This lets the fuel gauge IC map its coulomb counter to the new cell's actual discharge curve before high-current charging begins on an uncalibrated cell.

Sudden shutdown at 20–30% on the VS810 after a cell swap

This is a voltage cliff problem, not a capacity problem. The fuel gauge IC still holds the old cell's discharge curve in memory, so the percentage shown on screen does not match the new cell's actual voltage behaviour. Under modem radio or screen load, the new cell's voltage drops faster than the IC expects, and the phone cuts power before the displayed percentage reaches zero. One full discharge-recharge cycle forces the coulomb counter to rebuild the curve against the new cell. After that cycle, shutdowns at 20–30% stop.

Phone warm near the battery compartment on the first charge cycle

A freshly installed cell has higher internal impedance than a broken-in one. The charge IC pushes current into that resistance, and the heat is the energy loss across it. This is normal on the first one or two cycles and reduces as impedance settles. If the phone stays warm past the third full charge, check that the connector is fully seated — a partially connected cell forces the IC to work harder to maintain contact voltage. Confirm the back cover is flush and the battery tab is not folded under the cell.