SL860 Touch Compatible Battery 3.7V 1450mAh Li-ion

Bea-fon SL860 Touch — 3.7V Li-ion Replacement Battery (SL860)

This is a 3.7V Li-ion cell rated at 1450mAh (5.37Wh), built to fit the Bea-fon SL860 Touch and SL860_EU001B. It replaces the original cell when the phone no longer holds charge through a normal day of calls and texts. Dimensions are 64.80 x 44.00 x 5.20mm — check these against your original before ordering.

• SL860 Touch and SL860_EU001B compatibility: Both variants use the same battery bay dimensions, connector pinout, and 3.7V nominal voltage rail, so one cell covers both. No adapter or wiring change needed.
• Bench tested on actual hardware: We cycled the cell through full charge and discharge on the SL860 platform and logged BMS cutoff behaviour at both ends — low-voltage lockout triggers cleanly at the cell floor, and charge termination cuts correctly at full capacity.
• Fuel gauge recalibration on first use: On first installation, disable any fast-charge mode and run one complete discharge down to automatic shutdown, then charge fully to 100%. This gives the fuel gauge IC a clean reference curve against the new cell before high-current charging is applied to an uncalibrated cell.

Why the SL860 Touch reports wrong battery percentage after a cell swap

The SL860 Touch uses a fuel gauge IC that builds its charge model around the discharge curve of the original cell. When a new cell goes in, the IC is still reading against the old curve, so reported percentage drifts from actual state of charge. You may see the phone jump from 40% to 15% in minutes, or sit at 1% and keep running. One full discharge-to-shutdown followed by an uninterrupted charge to 100% resets the coulomb counter against the new cell's actual curve. After that cycle, percentage tracking stabilises.

Sudden shutdown at 20–30% on a replacement cell

This is a voltage cliff issue, not a capacity issue. Under modem load — during a call or a data burst — the cell voltage sags sharply, and the BMS trips the output before the fuel gauge registers low charge. It happens most often in the first few cycles on a new cell before the internal resistance settles. If shutdowns persist past the third full cycle, confirm the cell is seated flat with no connector flex. A resting open-circuit voltage of 3.85V or above after a full charge confirms the cell itself is not at fault.