About this replacement
Vivo X100 — 7.82V Li-Polymer Replacement Battery (BA06)
This is a 7.82V, 2400mAh Li-Polymer battery built to fit the Vivo X100 smartphone. It replaces part number BA06, the original cell used in the X100's dual-cell configuration. Capacity figures are sourced from product data — 18.77Wh total energy at rated voltage.
- Vivo X100 fit: The X100 uses a specific connector orientation and BMS handshake tied to the BA06 part number. This replacement matches that connector and communicates with the X100's fuel gauge IC the same way the original cell does.
- Bench tested on actual hardware: We ran charge and discharge cycles on the X100 with this cell installed. The BMS accepted the USB-PD handshake, current ramped correctly through CC and CV phases, and the fuel gauge IC logged cycle data without throwing calibration errors.
- First-cycle calibration on the X100: On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the X100's fuel gauge IC recalibrate against the new cell's discharge curve before high-current charging pushes amperage into an uncalibrated cell.
Sudden shutdown at 20–30% on the Vivo X100 after a cell swap
The X100's fuel gauge IC holds a learned discharge curve from the old, degraded cell. When a new cell is installed, the IC still uses that old curve to predict remaining charge. At around 20–30%, the new cell's actual voltage drops below what the modem and display demand under load — the phone cuts out even though the fuel gauge still shows charge remaining. This is a voltage cliff caused by a mismatched curve, not a faulty battery. One full discharge-charge cycle with fast charging off forces the coulomb counter to rebuild the curve against the new cell's actual chemistry.
USB-PD fast charge not triggering on the first cycle after replacement
After a cell swap, the X100's charge IC sometimes defaults to standard 5V charging on the first cycle because it has not yet confirmed the new BMS can handle higher current safely. This is a protection behaviour, not a pairing failure. Let the phone complete one full standard charge before reconnecting a fast charger — the charge IC will renegotiate the USB-PD contract on the second cycle. If fast charging still does not engage after two full cycles, check that the cable supports the required amperage for Vivo's FlashCharge protocol.