Vivo B-H6 iQOO Pro Compatible Battery 3.85V 4400mAh

Vivo iQOO Pro Series — 3.85V Li-Polymer Replacement Battery (B-H6)

This is a 3.85V, 4400mAh (16.94Wh) Li-Polymer replacement battery for the Vivo iQOO Pro and iQOO Pro 5G (model numbers V1916, V1916A). It replaces the original B-H6 cell when capacity has degraded or physical damage has affected performance. This battery restores the phone's ability to power its processor, display, and 5G modem at rated voltage.

• V1916 and V1916A platform fit: Both V1916 and V1916A use the same battery bay dimensions, connector pinout, and BMS handshake protocol — 77.40 x 63.64 x 5.54mm cell with a matching discharge curve the fuel gauge IC expects at 3.85V nominal.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on V1916 hardware. The BMS accepted the cell without error flags, and the charge IC stepped through standard CC/CV stages correctly on each cycle.
• First-cycle fast charge protocol: On first use after installation, disable fast charging and complete one full discharge-charge cycle at standard rate. This lets the fuel gauge IC recalibrate its coulomb counter against the new cell's discharge curve before high-current fast charging pushes elevated current into an uncalibrated cell.

Sudden shutdown at 20–30% on the iQOO Pro after a cell swap

The iQOO Pro's Snapdragon 855 Plus and 5G modem draw sharp current spikes under load. A new cell with a slightly different internal impedance profile can hit a voltage sag point the BMS reads as undervoltage before the displayed percentage reaches zero. The fuel gauge IC is still calibrated to the old cell's discharge curve, so it reports 25% while the actual cell voltage has already dropped below the BMS cutoff threshold. One complete slow discharge-charge cycle after installation resets the coulomb counter and aligns the percentage readout to the new cell's curve. After calibration, target a resting voltage of 3.85V at 50% charge when verifying correct gauge behaviour.

USB-PD or proprietary fast charge not working on first cycle after replacement

The iQOO Pro uses a proprietary fast charge protocol that requires a BMS handshake before the charge IC will accept elevated current. On the first cycle after a cell swap, the BMS may refuse the high-current handshake until the cell has completed at least one standard charge cycle — this is a protection behaviour, not a fault. Plug into a standard 5V/2A charger and allow a full charge to complete. On the second cycle, reconnect the fast charger and the protocol negotiation should proceed normally.