Prestigio PSP7511DUO Replacement Battery 3.8V 2000mAh

Prestigio PSP7511DUO — 3.8V Li-ion Replacement Battery (PSP7511)

This 3.8V, 2000mAh Li-ion cell replaces the original battery in the Prestigio PSP7511DUO dual-SIM smartphone. It fits the PSP7511DUO directly and restores power when the original cell no longer holds a charge. Capacity is 7.6Wh at rated voltage.

• PSP7511DUO fit: The PSP7511DUO uses a 3.8V nominal cell with a specific connector and form factor — 85.10 x 58.15 x 4.60mm. This replacement matches those dimensions and the BMS pin-out so the phone's charge IC communicates correctly with the new cell.
• Bench tested on actual hardware: We cycled this cell through a full charge and discharge on a PSP7511DUO unit. The BMS handshake completed without fault codes, and the charge IC accepted the cell through both trickle and constant-current phases without interruption.
• Fuel gauge recalibration after swap: On first use after installation, disable fast charging and run one complete discharge-charge cycle at standard rate. This lets the fuel gauge IC map the new cell's discharge curve before feeding it current at higher charge rates — skipping this step causes erratic percentage readings in the first few days.

Why the PSP7511DUO reports wrong battery percentage after a cell swap

The PSP7511DUO uses a fuel gauge IC that builds its state-of-charge model from a coulomb counter tracking the original cell's charge and discharge history. When you fit a new cell, that model no longer matches the actual discharge curve of the replacement. The IC continues using its stored curve, so it can report 40% when the cell is actually near cutoff voltage. One full uninterrupted discharge down to automatic shutdown, followed by a full charge to 100%, resets the coulomb counter reference and re-anchors the fuel gauge to the new cell's actual capacity.

Sudden shutdown at 20–30% on the replacement cell

This happens when the cell voltage drops below the BMS cutoff threshold under load — even though the OS is still showing charge remaining. On the PSP7511DUO, simultaneous dual-SIM radio activity and screen-on state can pull enough current to cause a sharp voltage sag in a new or cold cell. The fuel gauge reads an average voltage and misses the instantaneous sag that triggers the hardware cutoff. Let the phone warm to room temperature before use, and run the calibration cycle described above — after one full cycle, the fuel gauge tracks load-sag better and the premature shutdowns typically stop.