Dell CTOL7480-D1506CN Replacement Battery 7.6V 57Wh

Dell Latitude 12 7290 / CTOL7480 Series — 7.6V Li-ion Replacement Battery (0DM3WC)

This is a 7.6V, 7500mAh (57Wh) Li-ion replacement battery for the Dell Latitude 12 7290 and the CTOL7480 family, including the D1506CN and D1706CN configurations. It cross-references Dell part numbers 0DM3WC, F3YGT, KG7VF, and 451-BBYE, among others. Fit covers the Latitude 12 7000 series where these OEM part numbers apply.

• Latitude 12 7000 series compatibility: These models share a common 7.6V two-cell architecture with identical connector pinout and BMS handshake protocol. The same charge controller and EEPROM communication structure runs across the CTOL7480 variants, which is why one cell covers the full range.
• Bench tested on actual hardware: We ran this cell through charge, discharge, and BMS communication checks on a Latitude 7290 chassis. The BMS completed handshake without fault codes, charge current stepped down correctly at top-of-charge, and the protection circuit tripped cleanly at low-voltage cutoff.
• First-cycle calibration on Dell Latitude hardware: After installing, run one full discharge to hibernate-cutoff, then charge uninterrupted to 100%. This forces the BIOS battery learn cycle to reset against the new cell's actual capacity and clears the inaccurate health warning that appears on the status page after every cell swap.

BIOS reporting battery health as poor immediately after replacement

Dell's BIOS stores battery health data in the old cell's EEPROM. When a new cell is installed, the BIOS reads no historical cycle data and flags the battery as degraded or unknown. This is not a fault with the replacement cell — it is a data gap. Running a full discharge-to-hibernate followed by an uninterrupted charge to 100% initiates the learn cycle and writes fresh capacity data to the BIOS. After one or two complete cycles, the health indicator updates and the warning clears.

Laptop 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 gauge was mapped to the old cell and misjudges the voltage cliff — the point where cell voltage drops sharply under CPU and display load. The laptop interprets the sudden voltage sag as empty and triggers an emergency shutdown. Complete two full discharge-to-recharge cycles without interruption. After that, the fuel gauge IC recalibrates and the reported percentage at shutdown should align with actual cell voltage, typically below 3.0V per cell.