56Whr or 97Whr Li-Ion polymer There is an option
A MIL-SPEC durable design , fast performance, long battery life, and InfinityEdge display: these are a few of the many great things about the Dell Precision 5520. It's referred to as the "world's thinnest, lightest mobile workstation", and it really is. Weighing in at 4.4-lbs, this 15.6-inch machine is a lot easier to carry around than other business laptops in its size range - and it has a lot more to offer. The backlit keyboard has a nice design and offers a good typing experience, and the keys offer 1.4-millimeters of travel. The 4.1-inch x 3.1-inch touchpad supports multi-finger gestures which include two-finger scrolling. The touchpad is smooth to the touch and still offers a solid feel to the clicks. The 5520 has passed 14 tests for MIL-SPEC durability, meaning that it more than meets the standards the US military equipment has for ruggedness. It can operate in extremely cold and hot temperatures (from -20 degrees all the way up to 140 degrees F), and survive ...