BL-48ON LG Optimus M+ Replacement Battery 3.7V 1300mAh

LG Optimus M+ / MS695 — 3.7V Li-ion Replacement Battery (BL-48ON)

This is a 3.7V, 1300mAh Li-ion cell built to replace the BL-48ON battery in the LG Optimus M+ (MS695) and Optimus Plus (AS695). It fits the original battery bay and connects to the same three-pin contacts the phone uses for charge monitoring. Capacity matches the factory spec at 4.81Wh.

• MS695 and AS695 platform fit: Both the Optimus M+ and Optimus Plus share the same battery bay dimensions, connector pinout, and charge IC handshake — one cell covers the full variant group without modification.
• Bench tested on actual hardware: We cycled this cell through the MS695 charge IC and confirmed the BMS accepted charge termination correctly, with no false-full cutoff on the first cycle.
• Fuel gauge recalibration on first use: After installing this cell, run one complete discharge to shutdown followed by a full uninterrupted charge before using the phone normally. The Optimus M+ fuel gauge IC needs this full cycle to map its coulomb counter to the new cell's discharge curve — skipping it causes the percentage display to drift or jump in the first few days.

Sudden shutdown at 20–30% on the Optimus M+ after a cell swap

The Optimus M+ fuel gauge IC stores a charge curve calibrated to the original cell. When you swap in a new cell, the IC does not automatically reset its internal model. Under modem load — an active call or data session — the new cell's actual voltage drops faster than the IC predicts, and the phone shuts off before the display reaches 0%. One full discharge-to-shutdown and charge-to-100% cycle forces the coulomb counter to relearn the new curve. After that cycle, shutdowns below 20% stop.

Phone feels warm near the battery during the first charge after replacement

A new Li-ion cell has slightly higher internal impedance than a broken-in one. On first charge, the Optimus M+ charge IC pushes current into that higher impedance, which dissipates as heat. This is normal and resolves after one or two full cycles as the cell's impedance settles. If the back cover stays warm past the second full charge, check that no label or debris is caught between the cell and the battery cover restricting airflow. Surface temperature should drop to ambient within a cycle or two — if it does not, reseat the cell and confirm the contacts are clean.