The battery in your phone is almost certainly a single lithium-ion (also known as Li-ion, Lion or LiB) cell.
Most of us never think about the battery in our phone until it dies. When everything is working properly the battery should not be a part of the Android experience, other than not lasting long enough because we never put our phones down.
The only time we ever think about the battery is when we have to charge it.
According to Android Central, how you charge your phone can make a difference, though not nearly as much as some people think. Let’s have a look at the right way to take care of you battery and if it really matters.
Basic knowledge about your battery
A few facts about your phone’s battery make for a great starting point. We need to know the basics before we dive into the rest.
The battery in your phone is almost certainly a single lithium-ion (also known as Li-ion, Lion or LiB) cell. Li-ion batteries offer what’s called a high energy density (power output compared to size), have almost zero memory effect and offer a moderate self-discharge rate.
There are Li-ion batteries in all shapes and sizes, and while most of what we’re going to talk about apply to them all we’re going to focus on the one inside your phone.
The chemistry of your phone battery is usually lithium cobalt oxide-based. These types of cell offer a very high energy density but also pose some serious safety issues like the ones we saw with the Galaxy Note 7.
While the actual composition can vary from manufacturer to manufacturer, generally you have two electrodes, (one carbon-based and one lithium oxide-based) encased in a pressurised foil pouch filled with a lithium salt dissolved in an organic solvent as the electrolyte paste.
Charged lithium ions move from one electrode to the other through the conductive electrolyte, which is flammable.
The electrolyte gets very hot when the juice is flowing and a puncture of the foil can lead to a small explosion of very flammable fluid.
The companies that make Li-ion batteries are always working on ways to make them safer without lowering the amount of energy they can store. Graphene, Sulfur, and Hexafluorides are just some of the chemicals being used to try and build a better battery, and every model made is safer than the last. But lithium-ion cells are still inherently dangerous. That’s why the battery in your phone is more than just a cell — it makes things a lot safer when you regulate things.
The battery inside your phone is a power cell as described above coupled with sensors and other parts like voltage regulators and an external connector.
This electronic hardware monitors the electricity moving in and out of the battery as well as the capacity and temperature. They are there to shut down power instantly if they detect a short or dangerous temperature spike.
A lot of work went into making a battery for your phone that can deliver the power needed as safe as possible.
The memory effect
Battery memory effect is when the battery (not the cell itself) forgets the capacity that’s not regularly charged. It’s a weird concept that’s difficult to fully explain.
Li-ion batteries don’t have a memory effect.
If you charge your battery every time it goes down to 25 per cent and then remove it from the charger when it reaches 75 per cent every time, you’re only charging 50 per cent of the capacity.
The zero to 25 per cent that never discharged and the 75-100 per cent that is never charged will be forgotten.
This means that over time your battery thinks 25 per cent is zero per cent and 75 per cent is 100 per cent. You are unable to use half of the battery in this case.
As crazy as it sounds, it’s true. But not for Li-ion batteries. You don’t need to worry about any battery memory effect for the battery inside your phone.
From zero to 100
The battery in your phone has a “zone” that provides as much charge as possible without doing anything that affects the lifespan of the battery too much.
Completely draining a battery might cause it to die and not come back.
The smarts in the battery and your phone work together to make sure this doesn’t happen.
Overcharging a battery can cause heat that damages the cell inside it. Your phone and the battery itself work together to make sure this doesn’t happen, too.
Your battery and phone are smart and make sure you can’t fully discharge or overcharge things.
In a perfect world, you would keep your phone battery close to 50 per cent charged at all times by micromanaging the time it spends on the charger to top it off when needed.
This is because batteries have a useful life and it’s based on charge cycles.
A charge cycle is going from dead to full (inside that safe zone described above) one time. Most phone batteries are designed to last about 400 cycles.
That means if you let it run to zero then charge it to full 400 separate times the battery will no longer be able to hold a full charge and it will take more of the stored charge to normally operate your phone. Eventually, you’ll notice that it takes longer to charge it and it doesn’t last as long as it did when it was new.
This will happen to every battery eventually, but small “top-up” charges that don’t heat things up as much have less of an impact than long charges.
If you always run your battery down until it’s almost dead then plug your phone in until it’s full you’re putting more stress on it than doing a bunch of short charges.
We can’t say the difference is so small it doesn’t matter, but we can say that it’s probably not worth the inconvenience of charging your phone five minutes at a time all day long.
Charging at night
If you plug your phone in when you go to bed and let it charge all night, it still won’t overcharge the battery.
But it’s important to mention that you should never charge a lithium-ion battery unattended.
When the phone is fully charged the electronics in the battery tell your phone to stop sending electricity from the charger to the battery charging circuit.
Power still comes in, it just doesn’t work at recharging anything and goes back out to the wall socket (electricity travels in an unbroken loop to and from the power source).
If your phone is still powered on the battery will discharge because it’s being used.
When it discharges to a certain point, charging starts again. This cycle repeats until you unplug it in the morning.
A lot of work was done to make sure the cell inside the battery doesn’t overcharge at any time.
Even during the night while it’s on the charger. If you’re going to charge your phone overnight, make sure everything works properly and you’re charging properly.
That means you don’t have the phone under a blanket or laying on the rug while it’s plugged in or have it in a thick sealed case that keeps the heat in. Plug it in (or put it on a wireless charger) somewhere that it won’t get tangled up in your bedclothes or knocked to the floor.