Oppo A1 Pro Compatible Battery BLP981 3.87V 4600mAh

Oppo A1 Pro / PHQ110 — 3.87V Li-Polymer Replacement Battery (BLP981)

This is a 3.87V, 4600mAh Li-Polymer cell built to the BLP981 specification for the Oppo A1 Pro (PHQ110). It replaces the original internal battery when the existing cell can no longer hold charge, shuts down unexpectedly, or has swollen. Voltage and connector match the original so the phone's charge IC and fuel gauge IC receive the correct signal.

• A1 Pro and PHQ110 fitment: Both model designations refer to the same physical handset on different regional SKUs. They share the same battery bay dimensions (85.40 × 62.40 × 4.70mm), the same flex connector, and the same BMS handshake protocol — so one BLP981 cell covers both.
• Bench tested on actual hardware: We ran this cell through charge-discharge cycles on an A1 Pro unit, monitoring BMS communication and charge IC acceptance. The protection circuit triggered correctly at cutoff voltage and the charge IC negotiated without faults.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC map its coulomb counter against the new cell's actual discharge curve before high-current charging pushes current into an uncalibrated state.

Sudden shutdown at 20–30% on the BLP981 replacement cell

This happens when the fuel gauge IC is still calibrated to the old cell's discharge curve. The percentage reading is based on a voltage model built around the degraded original — the new cell hits a different voltage profile under modem or screen load, and the phone interprets that as a sudden drop to zero. It is not a fault in the replacement cell. One full slow-charge cycle after installation resets the coulomb counter and aligns the IC to the new cell. After that cycle, the percentage reading stabilises.

SUPERVOOC fast charge not accepted on the first cycle after installation

The Oppo SUPERVOOC protocol requires a handshake between the charger, the charge IC, and the battery BMS before elevated current is allowed. On a freshly installed cell, the BMS may complete that handshake only after the first standard charge cycle brings the cell to a known state. If the phone falls back to 5W standard charging on the first plug-in, that is expected behaviour. Complete one full charge at standard speed, then reconnect with the SUPERVOOC adapter — fast charge should negotiate normally at that point.