About this replacement
Motorola E360 — 3.7V Li-ion Replacement Battery (SNN5645A)
This is a 3.7V, 780mAh Li-ion replacement battery for the Motorola E360 candybar mobile phone. It replaces OEM part SNN5645A. Fits the E360 directly — same voltage, same connector, same form factor.
- E360 platform fit: The E360 runs a single-cell 3.7V Li-ion architecture with a straightforward connector and no complex BMS handshake. This cell matches that voltage rail and mechanical footprint exactly.
- Bench tested on actual hardware: We cycled this cell through full charge and discharge on the E360 platform. The charge IC accepted the cell without fault flags, and the BMS held the 4.2V charge cutoff correctly throughout testing.
- Fuel gauge recalibration on first use: On first installation, run one complete discharge down to automatic shutdown, then charge uninterrupted to 100% before use. The E360 fuel gauge IC calibrates its capacity curve against actual cell behaviour — skipping this step leaves the percentage readout offset against the new cell from the start.
Sudden shutdown at 20–30% on the E360 after a cell swap
The E360's fuel gauge IC was calibrated to the discharge curve of the original cell. A new cell has a slightly different voltage-to-capacity curve, particularly at the lower end. When the phone estimates 20–30% remaining, the actual cell voltage may already be near the 3.0V cutoff under screen or transmit load. The phone shuts down not because the cell is faulty, but because the gauge IC has not yet mapped the new curve. One full discharge-charge cycle corrects this — after that, the percentage readout tracks the new cell accurately.
E360 not powering on after the battery sat in storage
Li-ion cells self-discharge in storage. If the E360 has been unused for months, the cell voltage may have dropped below 2.5V — the threshold where the BMS locks out to prevent damage. The phone will show nothing when you press the power button, and a standard charger may not begin charging because the BMS rejects the charge request at that voltage. Connect the phone to a charger and leave it for 20–30 minutes without pressing anything — most E360 charge ICs will trickle current into a locked cell to bring it above the 2.8V re-enable threshold before resuming normal charge.