About this replacement
LG 1500 / G1500 — 3.7V Li-ion Replacement Battery
This is a 3.7V, 850mAh (3.15Wh) lithium-ion battery for the LG 1500 and G1500 mobile phone. It replaces the original cell when the phone no longer holds charge through a normal day. Drop it in when the original cell has degraded past the point of usefulness.
- LG 1500 / G1500 fit: Both model designations use the same physical cell format, connector orientation, and charge IC handshake — one cell covers both. The voltage rail is 3.7V nominal, matching the phone's onboard power management circuitry.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the bench. The BMS accepted the charge IC handshake without fault codes, and the cell held voltage above 3.5V through the discharge curve.
- Fuel gauge recalibration on first use: After fitting this cell, disable fast charging if the option is available and run one full discharge-to-charge cycle before normal use. The fuel gauge IC on the LG 1500 calibrates its coulomb counter against the cell's discharge curve — skipping this step causes the percentage readout to drift against the new cell's actual state of charge.
Why the LG 1500 reports wrong battery percentage after a cell swap
The fuel gauge IC stores a learned discharge curve from the original cell. When you install a new cell, that stored curve no longer matches the new cell's actual voltage-to-capacity relationship. The IC keeps reading against the old data until it can re-learn. One full discharge down to automatic shutoff, followed by a full charge to 100%, resets the coulomb counter and lets the IC build a fresh curve against the new cell. After that cycle, percentage readings stabilise.
Sudden shutdown at 20–30% on a fresh replacement cell
This happens when the cell voltage drops below the modem or screen load threshold before the percentage readout reaches zero — a voltage cliff specific to uncalibrated cells under high instantaneous draw. The fuel gauge IC thinks there is charge remaining, but the cell cannot sustain voltage under load at that state of charge. Run the full recalibration cycle described above. If shutdowns persist past the second cycle, check that the cell contact pins are fully seated — poor contact raises internal resistance and accelerates the voltage drop under load, triggering the BMS cutoff above 2.7V.