Simvalley SX-330 Replacement Battery 3.7V 1050mAh BK053465

Simvalley SX-330 / SX330 Dual Sim — 3.7V Li-ion Replacement Battery (BK053465)

This 3.7V 1050mAh Li-ion cell replaces the original battery in the Simvalley SX-330, SX330, SX330 Dual Sim, and Easy-5 smartphones. It matches the OEM physical footprint at 53.00 × 33.90 × 5.60mm and drops directly into the battery bay without modification. Capacity figures come from the product data: 1050mAh / 3.89Wh.

• SX-330 and Easy-5 platform fit: These models share an identical battery bay, connector pinout, and BMS handshake protocol. One cell covers all variants listed without adapter or rewiring.
• Bench tested on actual hardware: We cycled this cell through full charge and discharge on the SX-330 platform. The BMS accepted the handshake correctly, thermal cutoff triggered at expected thresholds, and the protection circuit held within spec under sustained screen-on load.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging and run one complete discharge-to-charge cycle. This lets the fuel gauge IC map the new cell's discharge curve before the charge IC pushes higher current into an uncalibrated cell — skipping this step causes erratic percentage readings.

Sudden shutdown at 20–30% on the SX-330 after a cell swap

The SX-330 shuts down mid-use — not at 0% — because the fuel gauge IC is still calibrated to the old cell's discharge curve. The new cell hits a voltage cliff faster than the IC expects, so the phone sees adequate percentage on screen right until the cell voltage drops below the modem's minimum draw threshold. The fix is one full discharge to automatic shutdown, then a full charge without interruption. After that cycle, the coulomb counter recalibrates and reported percentage aligns with actual cell state. Target a resting voltage of 4.18–4.20V at 100% to confirm the cycle completed correctly.

Phone warm near the battery compartment during first charge

A new Li-ion cell arrives from storage with elevated internal impedance compared to a cell that has been cycled. The charge IC pushes current into that higher-impedance cell, which dissipates more energy as heat than a broken-in cell would. This is normal for the first one or two charge cycles and typically resolves as internal impedance drops. If the phone remains warm past the second full charge cycle, check that the charger output does not exceed the rated input current — the SX-330 charge port accepts 5V input, so avoid chargers that force higher voltage protocols.