About this replacement
Oppo Reno6 / CPH2235 — 7.74V Li-Polymer Replacement Battery (BLP863)
This is a 2150mAh, 7.74V Li-Polymer cell for the Oppo Reno6 (model CPH2235), replacing OEM part BLP863. It fits directly into the Reno6 chassis and connects to the same flex ribbon the original cell uses. Capacity and voltage match the factory spec from the product data.
- Reno6 and CPH2235 fit: Both model references share the same physical footprint, connector pinout, and BMS communication protocol — the BLP863 cell covers both without any hardware modification.
- Bench tested on actual hardware: We ran the BLP863 through charge and discharge cycles on the Reno6 board. The BMS handshake completed correctly, charge IC accepted the cell, and no thermal events occurred during a full charge cycle.
- Fuel gauge recalibration on first use: After installation, disable fast charging and run one full discharge down to automatic shutdown, then charge to 100% on standard charge. This gives the Reno6's fuel gauge IC a clean reference curve against the new cell before high-current charging begins.
Sudden shutdown at 20–30% on the BLP863 replacement cell
The Reno6's fuel gauge IC builds its state-of-charge map from the discharge curve of whichever cell it last fully cycled. When a new cell goes in, the stored curve no longer matches the actual voltage-to-capacity relationship of the replacement. Under heavy load — screen at full brightness, modem active — the cell voltage drops faster than the gauge predicts, and the phone hits the hardware undervoltage cutoff while the OS still shows 25%. One full discharge-charge cycle on standard charge rewrites the coulomb counter reference and eliminates the premature cutoff.
VOOC fast charge not activating after a cell swap
Oppo's VOOC protocol requires the charge IC to verify cell impedance before it steps up current. A brand-new cell has higher internal impedance than a cycled cell, and the charge IC may refuse to enter fast-charge mode until it trusts the cell's response profile. On first charge after installation, use a standard 5V charger — not the VOOC brick — and let the cycle complete fully. After one standard cycle, impedance drops into the accepted range and VOOC resumes on the next charge.