Dell Latitude 7285 Keyboard Battery YX0XH 7.6V 4250mAh

Dell Latitude 7285 — 7.6V Li-Polymer Replacement Battery (YX0XH)

This is a 7.6V, 4250mAh (32.3Wh) Li-Polymer battery for the Dell Latitude 7285 2-in-1 detachable. It fits the keyboard base unit of the Latitude 7285 — not the tablet portion. Compatible OEM part numbers include YX0XH, WYCVV, C668F, and T16KJ.

• Latitude 7285 keyboard base compatibility: The 7285 splits power between the tablet and keyboard dock. This cell powers the base unit only. It runs the same 7.6V rail and connector pinout as the original, including the BMS data lines the Dell EC uses to read charge state.
• Bench tested on actual hardware: We ran this cell on a Latitude 7285 base unit and confirmed the BMS handshake completed without error. The EC recognised the battery, charge current ramped correctly, and the fuel gauge initialised without a fault code.
• BIOS learn cycle after install: After fitting this cell, run the laptop down to hibernate cutoff, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle. Without it, the system reports inaccurate health data because it is still reading calibration values from the old cell.

BIOS reporting poor battery health immediately after replacement

Dell's EC reads health data from EEPROM registers on the battery controller, not just live voltage. When you swap cells, the BIOS compares the new cell's reported parameters against the stored history from the old pack. Until a full learn cycle runs, it flags health as poor or unknown. One full discharge-to-hibernate followed by an uninterrupted charge to 100% writes new baseline data. After that cycle, the health warning clears on the next boot.

Latitude 7285 base battery showing 0% or "plugged in, not charging" after swap

This usually means the BMS handshake stalled during the first connection. The Dell EC can lock charge current if it does not receive a valid response from the battery controller within a set window. Disconnect the base from the tablet, remove the battery connector, wait 30 seconds, then reconnect. If the issue persists, check the connector pins on the keyboard base — a bent pin on the data line prevents the BMS from completing authentication. The charge line activates once the EC sees a valid voltage response, typically above 3.0V per cell.