Dell Latitude 7424 Replacement Battery 11.4V 0DMF8C

Dell Latitude 7424 / 5424 / 5420 — 11.4V Li-ion Replacement Battery (0DMF8C)

This is an 11.4V, 4200mAh (47.88Wh) lithium-ion battery for the Dell Latitude 7424, 5424, and 5420 notebook series. It replaces OEM part numbers 0DMF8C, 7WNW1, DMF8C, and covers P85G / P86G board variants. If your original cell is swollen, dead, or holding a fraction of its original charge, this is the direct swap.

• Latitude 5420 / 5424 / 7424 compatibility: These three models share the same 11.4V three-cell architecture, identical connector pinout, and the same BMS handshake protocol — which is why a single part number covers all three. The BIOS firmware on each recognises the same EEPROM signature from the OEM cell.
• Bench tested on actual hardware: We ran this cell on a Latitude 7424 unit and monitored BMS communication through a full charge cycle. The battery authenticated correctly, charge current tapered normally at top-of-charge, and no protection trip fired under a combined CPU stress and display load.
• Post-install calibration on Dell Latitude units: After fitting this cell, run one complete discharge to hibernate-cutoff, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle. Without it, the BIOS reads stale EEPROM data from the old cell and flags the new battery as poor health — even when the cell is full and healthy.

BIOS reporting poor battery health immediately after replacement

Dell's BIOS stores battery health data in EEPROM on the old cell. When you swap cells, the BIOS has no baseline for the new one and defaults to a poor health warning. This is not a fault with the replacement cell — it is a calibration gap. Running the battery learn cycle (full discharge to hibernate, then a full uninterrupted charge) gives the BIOS fresh data to write. After one complete cycle, the health warning clears and the fuel gauge reads accurately.

Latitude shutting down at 20–30% charge shown on screen

This happens when the fuel gauge IC has not yet calibrated against the new cell's actual voltage curve. The OS fuel gauge inherited state-of-charge estimates from the old battery's EEPROM data and those figures are now wrong. Under combined CPU and display load, the actual cell voltage drops faster than the stale estimate predicts — and the system hits the BIOS low-voltage shutdown threshold before the gauge reaches 0%. Run two full discharge-to-hibernate and charge-to-100% cycles to sync the fuel gauge IC to the new cell. After cycle two, the reported percentage should track actual remaining charge to within a few percent.