&gt; Unfortunately, even with this 84Wh battery, the battery life of the XPS 15 wasn&#x27;t tremendous. The blame for this lies almost certainly with that large screen. Dell&#x27;s own battery life estimates (which are in the same ballpark as ours, given some differences in testing methodology) suggest that swapping out the 4K panel for the 1080p one would extend battery life in similar workloads by 60 percent or more.<p>Why is Apple the only one that can build a 15&quot; retina laptop with 9-10 hours of battery life?