About this replacement
Oppo Reno5 Pro / Reno5 Pro 5G — 7.74V Li-Polymer Replacement Battery (BLP823)
This is a 7.74V, 2100mAh Li-Polymer replacement battery for the Oppo Reno5 Pro and Reno5 Pro 5G (models CPH2201, PDST00). It replaces OEM part BLP823 and fits the same internal cavity at 91.10 × 62.40 × 4.70mm. Swap it when your original cell no longer holds charge or causes unexpected shutdowns.
- Reno5 Pro and Reno5 Pro 5G compatibility: Both CPH2201 and PDST00 variants use the same BLP823 cell, voltage rail, flex connector, and BMS handshake — the 5G modem draws higher peak current, but the battery architecture is identical across both models.
- Bench tested on actual hardware: We cycled this cell on a Reno5 Pro unit and confirmed the BMS negotiates correctly with Oppo's charge IC — full charge acceptance was achieved and no false cutoff events were triggered under sustained load.
- First-cycle recalibration on the Reno5 Pro: On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC recalibrate its coulomb counter against the new cell's discharge curve before high-current charging pushes power into an uncalibrated cell.
Sudden shutdown at 20–30% on the Reno5 Pro after a cell swap
The Reno5 Pro's fuel gauge IC retains the discharge curve from the old, degraded cell. When the new cell arrives with a different impedance profile, the gauge miscalculates remaining charge. Under modem or screen load, voltage drops below the system cutoff threshold before the percentage display reaches zero. One full discharge-charge cycle without fast charging forces the coulomb counter to rebuild its model against the new cell.
VOOC fast charge not activating on the first cycle after replacement
Oppo's VOOC protocol requires a successful BMS authentication handshake before the charge IC allows high-current delivery. On a freshly installed cell, the BMS may default to standard 5V/1A charging on the first cycle while it verifies the cell parameters. This is not a fault — it clears after the first complete charge. If VOOC still fails to activate after two full cycles, confirm the flex connector is fully seated, as a partial connection breaks the data line the charge IC uses for protocol negotiation.