About this replacement
Poco F5 Pro 5G — 3.87V Li-Polymer Replacement Battery (BM5N)
This is a 3.87V, 5000mAh (19.35Wh) Li-Polymer cell for the Poco F5 Pro 5G (model 23013RK75G). It replaces the original BM5N battery when the existing cell degrades, swells, or can no longer hold a stable charge through a full day. Dimensions are 86.00 x 64.70 x 5.30mm — verify your existing cell before fitting.
- F5 Pro 5G platform fit: The F5 Pro 5G uses a dedicated BM5N cell matched to the Snapdragon 8+ Gen 1's power delivery rails. The battery connector, BMS handshake, and physical footprint are specific to this board — cells from other Poco or Redmi models will not seat or communicate correctly with this device's charge IC.
- Bench tested on actual hardware: We cycled the BM5N cell through charge and discharge on the F5 Pro 5G mainboard. The BMS accepted the cell without fault flags, charge current ramped correctly through CC/CV stages, and the fuel gauge IC registered capacity within expected tolerance across multiple cycles.
- First-cycle fast charge hold-off: After fitting this cell, disable fast charging for one complete discharge-charge cycle. The fuel gauge IC is still calibrated to the old cell's discharge curve. Running a full slow cycle first lets the coulomb counter re-anchor to the new cell before high-current fast charging begins pushing current into an uncalibrated state.
Sudden shutdown at 20–30% on the F5 Pro 5G after a cell swap
This happens because the fuel gauge IC is still running the discharge curve it mapped for the old, degraded cell. When load spikes — modem traffic, screen at full brightness, or a background sync — the new cell's actual voltage briefly dips below the IC's shutdown threshold even though the reported percentage looks safe. The result is an abrupt cutoff that feels like a fault but is a calibration mismatch. One full slow-charge cycle without fast charging forces the IC to re-map the curve against the new cell. After that cycle, shutdowns at 20–30% should stop.
F5 Pro 5G not powering on after the replacement cell sat in storage
Li-Polymer cells shipped or stored without a partial charge can drop below 2.5V per cell, triggering BMS lockout — the protection circuit opens and the device will not respond to the power button or a charger. Connect the phone to a 5V/2A USB-A brick, not a USB-PD fast charger, and leave it for 20–30 minutes without pressing anything. The slow trickle current is enough to nudge the cell above the BMS re-enable threshold, after which the phone will begin a normal charge cycle. If the screen stays dark past 45 minutes, the cell voltage is below recovery range and the cell itself needs replacement.