About this replacement
Dell Inspiron 15 5000 Series — 11.1V Li-ion Replacement Battery (TRHFF)
This is an 11.1V, 3870mAh (42.96Wh) lithium-ion battery for the Dell Inspiron 15, Inspiron 15 5000, Inspiron 15-5547, and Inspiron 5547 series laptops. It uses OEM part number TRHFF and crosses to 1V2F6, DFVYN, 58DP4, 5MD4V, and VVMKC among others. If your original battery no longer holds charge or the system reports degraded health, this cell is a direct swap.
- Inspiron 15 5000 series compatibility: These models share the same 11.1V three-cell configuration, connector pinout, and BMS handshake protocol. The battery management system expects the same charge curve across all variants in this family, so one cell covers the full range.
- Bench tested on actual hardware: We ran this cell on an Inspiron 15-5547 chassis. The BMS completed the charge handshake without fault codes, accepted a full charge cycle to 42.96Wh, and discharged cleanly to the low-voltage cutoff without tripping protection prematurely.
- Post-install calibration cycle: After fitting this cell, run the laptop down to hibernate-cutoff on battery only, then charge uninterrupted to 100% without using the machine. This resets the BIOS battery learn cycle and clears the inaccurate health warning that appears on the first boot after any cell swap.
BIOS reporting battery health as poor immediately after replacement
Dell's BIOS reads health data from the battery's EEPROM on every boot. The old cell wrote its own wear metrics and cycle count to that register, and the BIOS cached those figures. When a new cell arrives with a clean EEPROM, the BIOS interprets the mismatch as a degraded or unknown battery. Running one full discharge-to-hibernate followed by an uninterrupted charge to 100% forces the BIOS to re-run its learn cycle against the new cell's actual capacity. After that single calibration, the health status resets and the warning clears.
Laptop shutting down at 20–30% charge shown on screen
This happens when the cell voltage drops below the BMS cutoff threshold before the fuel gauge IC predicts it should. Under combined CPU and display load, the Inspiron 15 draws enough current to push the cell into a voltage cliff — the cell voltage collapses faster than the gauge tracks, and the system shuts down to protect the hardware. The fuel gauge IC needs two to three full charge-discharge cycles to recalibrate its model against the new cell's actual discharge curve. After three full cycles, the gauge and the real cutoff voltage align and the early shutdown stops.