Hi Lifehacker, Why does the battery life of my phone vary so much? Some charges last for a day or two and others last less than 12 hours. I'm certain that I'm not downloading anything in the background or doing anything that would drain the battery faster than normal. I have a Nokia Lumia 920. Any thoughts? Thanks, Drain Pain
Variation in battery life is normal. Phone calls, app downloads, internet browsing, photo uploads, video playback and various other factors drain battery at different rates. You may not think the nature of your usage varies much, but the reality is a lot less uniform.
For example, the number of calls you make and their duration obviously changes from day to day. Similarly, sometimes you might happen to use your phone outside more, with the screen's automatic brightness level adjusting accordingly. There are countless permutations like this which can change how long your battery lasts in-between charges.
The amount of juice left on your battery when you plug it in for a re-charge can also affect how long it lasts. According to the Battery University website, the smaller the depth of discharge, the longer the battery will last. In other words, try to "top up" your battery instead of waiting for it to go completely dead. (Partial discharges on Li-ion batteries do not shorten the lifespan; there is no memory involved.)
While it's difficult to keep your phone's battery on a rigid schedule, there are ways to make it last longer in general. Manually adjusting your phone's brightness to the lowest setting can net you a few extra hours of battery life compared to the maxed out setting. Shutting down apps rather than keeping them running in the background has also been found to improve battery life.
If you want to learn more about what's eating into your battery, try installing a battery tracking app like Battery Sense and Nokia's own Battery Monitor. You can also glean some relevant tips from our iPhone and Android battery saver guides.
If any readers have additional battery extending tips to share, let DP know in the comments section below.
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