For an object that barely ever leaves our palms, the smartphone can sometimes feel like an arcane piece of wizardry. And nowhere is this more pronounced than when it comes to the fickle battery, which will drop 20 per cent charge quicker than you can toggle Bluetooth off and give up the ghost entirely after a couple of years of charging.
Even when your battery is at 100%, there’s still room for more charge
Increasing the available charge within a battery reduces the number of times that battery can be charged and discharged without being damaged internally
- To make batteries last for hundreds or thousands of charge cycles, manufacturers place limits on the amount of juice that batteries can discharge
- While it is possible to charge a battery beyond 100%, the only way to do that is to pull out more of those crucial lithium ions
Leaving a charger plugged in at the wall and turned on wastes energy
With phone chargers and other ‘dumb’ cables that just have a wire, they probably aren’t drawing any energy at all if there’s no device plugged in.
- When it comes to TV or laptop cables, these are a little more clever as they often draw a small amount power while they’re essentially waiting for the TV or other device to boot up.
Charging past 100% will damage your battery
A ‘trickle charge’ mechanism cuts off the charger after the phone has reached 100%, and only tops up the battery when it drops down a little
- The problem is that you are keeping the charge level at 100%, which puts the battery under a certain amount of strain
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Powering off a device occasionally helps preserve battery life
Before lithium-ion batteries, it was impossible to get an accurate reading of the battery charge without fully discharging and then recharging the battery.
- Modern batteries are capable of reading their state no matter their level of charge, and when your device isn’t in use the strain on the battery is almost the same as if it was off altogether.
Wi-Fi and Bluetooth on in the background drain battery life
Reducing screen brightness and the time it takes your phone to go to sleep are also easy ways to extend your battery life.
- If you can connect to something stable, like if there’s WiFi on the train, it is probably better to connect to that.
Batteries perform worse when they’re cold
This is because of the liquid electrolytes that fill the gaps between the lithium cobalt oxide and graphite layers.
- At high temperatures, these electrolytes start to break down, causing the battery to degrade over the course of just a few hundred charge cycles.
You should let the battery get all the way down to 0 per cent before recharging
Batteries are under the most strain when their fully charged or completely empty
- The real sweet spot for a battery is 50 per cent charge
- This means that half of its moveable lithium ions are in the lithium cobalt oxide layer and the other half in the graphite layer
Using an unofficial charger damages your phone
Some off-brand chargers might not have such rigorous safety settings.
- If too much current is delivered to a battery, that could mean ripping out too many of those lithium ions and leading to the same kind of degradation.
Charging your phone through a computer or laptop won’t damage the battery
The more slowly you charge a battery, the less strain put on lithium ions and the structures accepting them, and the less potential damage to the battery.
