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I fear that we in the tech media shoulder some responsibility for making people worry -- sometimes to the point of obsession -- about their smartphone's battery life. It amazes me how close of an eye some smartphone owners keep on their devices.
We're constantly monitoring our phone's health.
To be fair, I'm like that, too. A bit. No, not really. A lot.
And if there's one thing that we battery watchers get good at spotting, it's when the battery is discharging faster than normal. And there's no easier thing to notice than a battery going from 100% to 99%.
When the battery was new, it may well have remained at 100% for a few hours. But after a few months of wear, that tick-over from 100% to 99% happens a lot quicker.
But why? Is this a problem?
No, it's nothing more than normal battery wear.
Every charge/discharge cycle that your iPhone goes through wears the battery a little.
According to Apple, the battery in your iPhone is designed to retain up to 80% of its original capacity at 500 complete charge cycles.
This, in turn, affects how quickly your iPhone's battery drops. That is, an old iPhone charged to 100% holds less charge than a new iPhone charged to 100% because of this wear.
But it gets more complicated.
If you watch that Maximum Capacity figure, you'll notice -- when your iPhone is new -- that it takes weeks, maybe months, before that 100% maximum capacity rolls over to 99%.
Why is that?
Because the battery inside your iPhone has a higher actual capacity than Apple claims. Apple underpromises on the capacity because new batteries have a natural variation in capacity, and Apple would prefer that your battery has slightly more capacity -- not less -- than what's in the spec sheet.
If you're interested, you can actually get iOS to show you how much capacity your battery had when new, what its current capacity is, what its rated capacity is, and how many charge cycles it's been through.
Confused? Don't worry! Put simply, this means that when your battery is new, it can hold more power than its rated capacity; and because of this, it looks like it can stay at that 100% mark for longer.
So, is this slow erosion of how long your battery will stay at 100% a problem?