Revive Your Dell Latitude E5440/E5540 with the 65Wh High-Capacity Battery Is your Dell Latitude E5440 or E5540 laptop dying mid-work, meetings, or travel? Our high-performance 65Wh Li-ion laptop battery is engineered to restore long-lasting power, matching the reliability of Dells original batteries. Designed for seamless compatibility with two of Dells most popular Latitude models, its the ideal replacement for worn-out cellskeeping your productivity on track all day.