OnePlus 12R 5G BLPA33 Replacement Battery 7.82V 2550mAh

OnePlus 12R 5G / Ace 3 5G — 7.82V Li-Polymer Replacement Battery (BLPA33)

This is a Li-Polymer replacement battery for the OnePlus 12R 5G and Ace 3 5G (CPH2611, PJE110). It runs at 7.82V nominal and carries 2550mAh (19.94Wh) of capacity. It fits devices where the original BLPA33 cell has degraded, swollen, or stopped holding a charge.

• 12R 5G and Ace 3 5G platform fit: Both models share the same chassis dimensions, battery bay, and BMS handshake protocol — the BLPA33 connector and voltage rail are identical across CPH2611 and PJE110 variants. No adapter or modification needed.
• Bench tested on actual hardware: We cycled this cell through full charge and discharge on a CPH2611 unit. The BMS accepted charge current correctly, cell voltage held steady under display and modem load, and no thermal events occurred during fast-charge cycles.
• First-cycle fuel gauge recalibration: After installation, disable SUPERVOOC fast charging and run one complete discharge-to-charge cycle at standard current. This lets the fuel gauge IC map its coulomb counter against the new cell's discharge curve before high-current charging is applied to an uncalibrated cell.

Why the OnePlus 12R 5G reports wrong battery percentage after a cell swap

The OnePlus 12R 5G uses a coulomb-counting fuel gauge IC that builds its accuracy from learned discharge curves of the original cell. Swap the cell and that learned data no longer matches the new cell's chemistry profile. The gauge continues using the old curve, which shifts percentage readouts — sometimes by 10–20%. One full discharge to 0% and a complete charge to 100% forces the IC to re-anchor its reference points to the new cell. After that single calibration cycle, percentage accuracy stabilises.

Sudden shutdown at 20–30% on the replacement BLPA33

This is a voltage cliff issue, not a capacity problem. The new cell's internal resistance profile differs slightly from the aged cell the fuel gauge was calibrated to, so the gauge reads 20–30% remaining while the actual cell voltage has already dropped below what the modem and display draw can sustain. The BMS trips and shuts the phone down to protect the cell. Run the recalibration cycle described above — one full discharge to 0% and charge to 100% — and the fuel gauge IC will correctly anticipate the voltage drop before it becomes a cutoff event. After calibration, the shutdown floor typically shifts back to below 5%.