About this replacement
UMI UMIDIGI One Pro — 3.85V Li-Polymer Replacement Battery (1ICP/5/64/58)
This is a 3.85V, 3250mAh (12.51Wh) lithium-polymer cell for the UMIDIGI One Pro smartphone. It replaces the original internal battery when the existing cell has degraded, swells, or no longer holds a useful charge. Part number 1ICP/5/64/58 matches the OEM specification for this device.
- UMIDIGI One Pro fit: The One Pro uses a dedicated battery bay sized for this 75.76 × 64.54 × 4.50mm cell. The connector pinout and BMS communication lines match the phone's charge IC directly — no adapters or modifications needed.
- Bench tested on actual hardware: We cycled this cell through the UMIDIGI One Pro's charge IC and confirmed BMS handshake, overvoltage cutoff at 4.35V, and undervoltage protection triggering correctly below 3.0V under load.
- Fuel gauge recalibration on first use: On the first cycle after installation, disable fast charging and run one full discharge down to automatic shutdown, then charge uninterrupted to 100%. This lets the phone's coulomb counter map the new cell's discharge curve before fast-charge current is applied to an uncalibrated cell.
Sudden shutdown at 20–30% on the UMIDIGI One Pro after a cell swap
A new lithium-polymer cell has a slightly different internal resistance profile than the worn cell the fuel gauge IC was trained on. Under peak loads — screen at full brightness, LTE active, GPS running — the phone's power rail demands a current spike the gauge hasn't accounted for yet. Voltage drops faster than predicted, the IC reads it as a hard cutoff threshold, and the phone shuts off even though percentage still showed mid-range. One complete uninterrupted discharge-charge cycle resets the coulomb counter and eliminates this behaviour.
USB-PD or fast charge not activating on the first cycle after replacement
After a battery swap, the charge IC on the UMIDIGI One Pro sometimes defaults to standard 5V/1A charging on the first cycle because the BMS on the new cell hasn't yet completed its authentication handshake with the phone's power management unit. This isn't a fault with the cable or charger. Run one full standard charge to 100%, let the phone sit at rest for two minutes, then reconnect the fast charger — the protocol negotiation completes correctly on the second session. If fast charge still doesn't activate, confirm the charger outputs at least 9V/2A.