On Windows, you can generate a battery health report that shows you the “design capacity” that your battery had when it arrived from the factory and the “full charge capacity” it currently has. You can check the health and capacity of your battery on pretty much any device, too. It won’t make the battery last any longer, but it will help the hardware understand how much capacity the battery has left and make more accurate estimates. You can recalibrate a battery by draining it down to empty before charging it back to full capacity. But, if you find your device dying when the operating system reports 20% or 10% battery life left, the battery may need recalibration. Circuitry on the battery itself generally reports the battery’s capacity and health to the operating system. Some devices are better at understanding how much power they have. The hardware that monitors how much capacity the battery has left may have an inaccurate estimate, which why a device might die when the operating system is still reporting 10% or even 20% battery power left. In other words, they won’t hold as much power.
RELATED: How to Calibrate Your Laptop's Battery for Accurate Battery Life Estimatesīatteries suffer wear and tear as you use them. If the Battery Dies Without Warning, It Doesn’t Know How Much Juice it Has Now hover over the battery icon in the SysTray (the right side of the taskbar which has the ethernet/wi-fi button and other necessary buttons) in taskbar. It can’t predict the future, only guess based on current conditions. Do something in the laptop until the battery level is below 95. It’s similar to why progress bars can be so inaccurate. In other words, your device makes an estimate based on the current rate of battery drain. Even if you’re just browsing the web, some websites–especially ones with video ads–use more system resources than others. For example, Windows might be installing updates–that will use more CPU resources, drain battery power more quickly, and lower the estimate.
This estimate can also fluctuate based on the work your computer is doing in the background.