About this replacement
Oppo Reno12 / CPH2625 — 3.91V Li-Polymer Replacement Battery (BLPA59)
This is a 4450mAh (17.4Wh) Li-Polymer cell built to replace the BLPA59 battery in the Oppo CPH2625, Reno12, and Reno12 5G. It runs at 3.91V nominal and slots into the same footprint as the original — 88.80 × 63.40 × 4.70mm. If your Reno12 shuts down unexpectedly, won't hold a charge, or the percentage jumps around, a worn cell is usually the cause.
- CPH2625, Reno12, Reno12 5G compatibility: These three model designations share the same battery bay, BMS handshake protocol, and connector pinout. The BLPA59 part number covers all three — there is no separate variant per region SKU.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the Reno12 platform and confirmed the BMS accepted it without triggering an overcharge or undervoltage cutoff. Charge IC communication checked out across VOOC and standard USB-C modes.
- Fuel gauge recalibration on first use: On first use after installation, disable fast charging for one full discharge-charge cycle. This lets the fuel gauge IC map its coulomb counter against the new cell's actual discharge curve before high-current VOOC charging pushes load into an uncalibrated cell.
Sudden shutdown at 20–30% on the Reno12 after a cell swap
The Reno12's fuel gauge IC stores a learned discharge curve from the original cell. When you install a new cell, that stored curve no longer matches the actual voltage-versus-capacity profile of the replacement. Under peak modem or display load, the cell voltage briefly dips below the BMS protection threshold — the phone reads it as critically low and cuts power even though the cell still has usable capacity. One complete slow discharge to near-zero followed by a full charge resets the coulomb counter and eliminates most of these early shutdowns.
VOOC fast charge not initiating on the first cycle after replacement
Oppo's VOOC protocol requires a handshake between the charge adapter, the charge IC on the board, and the battery BMS. On a fresh cell that hasn't completed its first cycle, the BMS sometimes responds outside the expected voltage window and the charge IC falls back to standard 5V input instead of initiating the VOOC current ramp. This isn't a fault with the adapter or the replacement cell — it resolves after one standard charge cycle brings the cell into the calibrated voltage band. Charge once via standard USB, let it complete fully, then reconnect your VOOC adapter.