About this replacement
Xiaomi Mi Pad 4 — 3.8V Li-Polymer Replacement Battery (BN60)
This is a 3.8V, 5800mAh lithium-polymer battery for the Xiaomi Mi Pad 4 and Mi Pad 4 WiFi (model numbers M1806D9W and M1806D9E). It replaces the original BN60 cell when the tablet no longer holds charge or shuts down unexpectedly. Capacity matches the factory specification at 22.04Wh.
- Mi Pad 4 platform fit: The Mi Pad 4 and Mi Pad 4 WiFi share the same battery bay dimensions and BMS handshake protocol. Both variants run the BN60 cell on a 3.8V nominal rail with the same connector pinout, so one part covers the full lineup.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on Mi Pad 4 hardware. The BMS accepted the new cell without fault flags, and the charge IC brought voltage up through each stage without thermal cutoff events.
- Fuel gauge recalibration after swap: After installation, run one full discharge to automatic shutoff, then charge uninterrupted to 100%. This forces the fuel gauge IC to recalibrate against the new cell's voltage curve and eliminates the inaccurate percentage readings that commonly appear after a battery replacement.
Mi Pad 4 shutting down at 15–25% remaining after battery swap
This happens because the fuel gauge IC is still referencing the voltage curve of the old, degraded cell. Under the combined load of the display at mid-brightness and active WiFi, voltage drops faster than the IC expects at that reported percentage. The tablet interprets this sag as a critically low state and triggers a protective shutdown. Run one full discharge-to-shutoff cycle followed by an uninterrupted charge to 100% — after that cycle the gauge recalibrates and the premature cutoffs stop.
Fast charging unavailable on Mi Pad 4 after battery replacement
The Mi Pad 4 uses Xiaomi's proprietary charge negotiation over the USB port. After a battery swap, the charge controller may default to standard 5V input until it completes one full accepted charge cycle on the new cell. Plug in using the original Xiaomi charger and cable — third-party adapters often fail the handshake entirely. Let the tablet complete one full charge uninterrupted to 100%, and fast charge will re-engage on subsequent sessions.