About this replacement
Dell Mini 3 Series — 3.7V Li-ion Replacement Battery (H11S22)
This 3.7V Li-ion cell replaces the original battery in the Dell Mini 3, Mini 3i, Mini 3iX, and Aero smartphones. Capacity is 920mAh (3.4Wh), matching the OEM specification. It fits the physical battery bay and uses the same connector as the factory cell.
- Mini 3 family compatibility: The Mini 3, Mini 3i, Mini 3iX, and Aero all share the same 45.30 × 38.98 × 5.62mm battery bay, the same 3.7V voltage rail, and the same connector pinout. One cell covers the full group.
- Bench tested on actual hardware: We cycled this cell through full charge and discharge on the Mini 3 platform. The BMS accepted the charge handshake without fault flags on the first cycle, and the protection circuit tripped correctly at low-voltage cutoff.
- Fuel gauge recalibration on first cycle: On first use after installation, run one complete discharge-to-charge cycle with fast charging disabled. This lets the fuel gauge IC map the new cell's discharge curve before it begins reporting percentage data to the OS.
Sudden shutdown at 20–30% on the Dell Mini 3 after a cell swap
This is a voltage cliff issue, not a capacity fault. A fresh cell has a slightly different discharge curve than the aged cell the fuel gauge IC was calibrated against. When the modem or screen pulls a high current burst, the cell voltage drops below the OS shutdown threshold even though the coulomb counter still shows charge remaining. Running one full discharge-charge cycle without fast charging lets the fuel gauge IC recalibrate its curve to the new cell. After that cycle, the reported percentage and actual cutoff voltage will align.
Device not powering on after the replacement cell sat in storage
If this cell has been stored discharged for an extended period, the BMS may have locked out below 2.5V per cell to prevent damage. The phone will show no response — no boot screen, no charge indicator. Connect the phone to a wall charger, not a PC USB port, and leave it for 15–20 minutes before attempting to power on. A wall charger delivers consistent 5V at sufficient current to trigger the BMS recovery threshold and bring the cell back into the normal charge window.