8 tips to extend the lifespan of your phone battery

How to preserve a smartphone’s fastest-degrading component

It’s harder to replace your phone’s lithium-ion battery than it is to treat it right in the first place. Many smartphones don’t provide easy user access to their batteries. That includes all iPhones and many flagship Android phones from brands such as Samsung. Official battery replacements can be expensive or inconvenient (try getting an official battery replacement at an Apple Store this year). There are also environmental concerns. Smartphones are, frankly, an environmental disaster and extending the lifespan of your phone battery helps mitigate that.

Here are some things you can do to preserve and extend the lifespan of your phone battery. By battery lifespan, I mean how many years and months your battery will last before it needs to be replaced. In contrast, battery life refers to how many hours or days your phone will last on a single charge.

1. Understand how your phone battery degrades.

With every charge cycle, your phone battery degrades slightly. A charge cycle is a full discharge and charge of the battery, from 0% to 100%. Partial charges count as a fraction of a cycle. Charging your phone from 50% to 100%, for example, would be half a charge cycle. Do that twice and it’s a full charge cycle. Some phone owners go through more than a full charge cycle a day, others go through less. It depends on how much you use your phone and what you do with it.

Battery manufacturers say that after about 400 cycles a phone battery’s capacity will degrade by 20%. It will only be able to store 80% of the energy it did originally and will continue to degrade with additional charge cycles. The reality, however, is that phone batteries probably degrade faster than that. One online site claims some phones reach that 20% degradation point after only 100 charge cycles. And just to be clear, the phone battery doesn’t stop degrading after 400 cycles.

If you can slow down those charge cycles — if you can extend the everyday battery life of your phone — you can extend its battery lifespan also. Basically, the less you drain and charge the battery, the longer the battery will last. The problem is, you bought your phone to use it. You have to balance saving battery life and lifespan with utility, using your phone how and when you want it. Some of my suggestions below may not work for you. On the other hand, there may be things that you can implement fairly easily that don’t cramp your style.

There are two general types of suggestions here. Suggestions to make your phone more energy efficient, slowing battery degradation by slowing down those charge cycles. Reducing screen brightness would be an example of this type of suggestion. There are also suggestions to reduce stress and strain to your battery, affecting its lifespan more directly. Avoiding extremes of heat and cold would be an example of this second type.

2. Avoid extremes of heat and cold. If your phone gets very hot or cold it can strain the battery and shorten its lifespan. Leaving it in your car would probably be the worst culprit if it’s hot and sunny outside or below freezing in winter.

3. Avoid fast charging.

Charging your phone quickly stresses the battery. Unless you really need it, avoid using fast charging.

In fact, the slower you charge your battery the better, so if you don’t mind slow charging overnight, go for it. Charging your phone from your computer as well as certain smart plugs can limit the voltage going into your phone, slowing its charge rate. Some external battery packs might slow the speed of charging, but I’m not sure about that.

4. Avoid draining your phone battery all the way to 0% or charging it all the way to 100%.

Older types of rechargeable batteries had ‘battery memory’. If you didn’t charge them to full and discharge them to zero battery they ‘remembered’ and reduced their useful range. It was better for their lifespan if you always drained and charged the battery completely.

Newer phone batteries work in a different way. It stresses the battery to drain it completely or charge it completely. Phone batteries are happiest if you keep them above 20% capacity and below 90%. To be extremely precise, they’re happiest around 50% capacity

Short charges are probably fine, by the way, so if you’re the sort of person that finds yourself frequently topping up your phone for quick charges, that’s fine for your battery.

Paying a lot of attention this one may be too much micromanagement. But when I owned my first smartphone I thought battery memory applied so I generally drained it low and charged it to 100%. Now that I know more about how the battery works, I usually plug it in before it gets below 20% and unplug it before completely charged if I think of it.

5. Charge your phone to 50% for long-term storage

The healthiest charge for a lithium-ion battery seems to be about 50%. If you are going to store your phone for an extended period, charge it to 50% before turning it off and storing it. This is easier on the battery than charging it to 100% or letting it drain to 0% before storage.

The battery, by the way, continues to degrade and discharge if the phone is turned off and not being used at all. This generation of batteries was designed to be used. If you think of it, turn the phone on every several months and top the battery up to 50%.

Tips to extend battery life

The tips above address the battery lifespan directly. Battery lifespan is also affected by battery life, how long your phone lasts on a single charge. Improving battery life extends the lifespan of the battery by slowing down those charge cycles.

6. Turn down the screen brightness.

A smartphone’s screen is the component that typically uses the most battery. Turning down the screen brightness will save energy. Using Auto Brightness probably saves battery for most people by automatically reducing the screen brightness when there’s less light, although it does involve more work for the light sensor.

The thing that would truly save the most battery in this area would be to manage it manually and fairly obsessively. That is, manually set it to the lowest visible level every time there’s a change in ambient lighting levels.

Both Android and iOS give you options to turn down overall screen brightness even if you’re also using auto-brightness.

7. Reduce the screen timeout (auto-lock)

If you leave your screen without using it, it will automatically turn off after a period of time, usually one or two minutes. You can save energy by reducing the Screen Timeout time (called Auto-Lock on iPhones). By default, I believe iPhones set their Auto-Lock to 2 minutes, which might be more than you need. You may be fine with 1 minute, or even 30 seconds. On the other hand, if you reduce auto-lock or screen timeout you may find your screen dimming too soon when you’re in the middle of reading a news story or recipe, so that’s a call you’ll need to make.

I use Tasker (an automation app) to change the screen timeout on my Galaxy S7 depending on what app I’m using. My default is a fairly short screen timeout of 35 seconds, but for apps where I am likely to be looking at the screen without using it, such as news and note-taking apps, I extend that timeout to over a minute.

8. Choose a dark theme.

My phone, the Galaxy S7, has an OLED screen. To display black it doesn’t block the backlight with a pixel like some iPhones and many other types of LCD screens. Instead, it doesn’t display anything at all. The pixels displaying black just don’t turn on. This makes the contrast between black and color very sharp and beautiful. It also means that displaying black on the screen uses no energy, and darker colors use less energy than bright colors like white. Choosing a dark theme for your phone, if it has an OLED or AMOLED screen, can save energy. If your screen does not have an OLED screen — and this includes all iPhones before the iPhone X — a dark theme won’t make a difference.

I found a dark theme I like in the Samsung store, and there are some excellent free icon pack apps for Android out there that focus on darker-themed icons. I use Cygnus Dark, Mellow Dark, Moonrise Icon Pack, and Moonshine. I use the Nova Launcher App to customize the appearance of app icons and often remove the name of the app if it’s clear enough from the icon what it is. That removes white space off of the screen, and I also think it looks nice and is less distracting.

Some people find a darker theme is easier on the eyes in terms of preventing eye strain, and less light overall may mean less blue light, which can affect sleep patterns.

Many apps include a dark theme in their settings. For example, I have Google Books set to a dark theme, where the virtual ‘page’ is black instead of white and the letters are white. Most of the pixels display black (are turned off) and use no energy.

I’m less familiar with customization and dark themes for iPhones. My understanding is that iPhones are somewhat harder to personalize. So far, though, only the iPhone X series have OLED screens so they are the only iPhones that would see energy savings from a dark theme.