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ELI5: Why does my phone use (or seem to use) battery faster when it gets lower?(r/explainlikeimfive)
If your battery is low, it actually takes more energy for your phone to draw energy from the battery to use.
Think about it like a CapriSun. When the pouch is full, it takes almost no energy for you to draw that delicious juice out of the container, but when it starts to get empty, you have to work harder to get all the juice out. When the battery in your phone is low, the components in your phone have to work harder to get the energy it needs from your emptying battery.
Here is a link about it: batteryuniversity.com/learn/article/calculating_th…
Also, I had the same problem, so I purchased one of these: www.amazon.com/Anker-10000mAh-Portable-Generation-…
It has worked wonderfully! They make smaller ones as well. I purchased one of the “Lipstick” models for my girlfriend, she likes it as well.
I’m able to get at least a full charge on my tablet and my phone, with plenty left to spare off of a single charge of the one I purchased for myself.