Get the best battery life from your device

Note: Although this article is aimed at Android devices, the principles within apply to all lithium-ion rechargeable batteries that are found in mobile phones, like Samsung smartphones, the iPhone, or other iOS devices like the iPad, tablets, and even PC laptops or MacBook computers.


For those who want the (TL;DR) quick version, we'll begin with the summary.

The most important tip to extending your device's battery life and prolonging battery health is to not constantly overcharge or undercharge the battery, or to overheat it.

Keeping the battery between 25% to 85% helps avoid the degradation that happens between deep discharge and charge cycles i.e. when going from 0% to 100% and vice versa.

The best operating temperature range for lithium-ion (or Li-ion) batteries, the kind used in mobile devices, is between 15 °C to 30 °C (59 °F to 86 °F).

Using Charger Alert for Android can help you maintain these optimal battery conditions by alerting you when your battery is too low, full enough, or too hot, so that you can take the appropriate action.


Extending our device's battery life and prolonging the battery health is important, especially now that we rely on our mobile phones in our daily lives and expect them to be available to us when we need them.

Since most mobile phones now have internal batteries integrated within the handset and are non-replaceable (or make battery replacement difficult), a bad battery that drains fast or charges slowly means having to replace the whole mobile device, which is expensive and a waste, especially if the rest of the handset is functioning perfectly fine.

Therefore prolonging the battery life and health of your mobile device is a worthy investment, and this article will help you with some tips and suggestions to do just that.

How to save battery using your mobile device

Most articles about getting the most out of your mobile battery life focus on the way you should use the device, like limiting usage, the apps running, reducing the amount of screen time, turning down screen brightness, etc. Those are useful suggestions that you may already be familiar with. In case you aren't, here is a brief list of tips you can use:

  • Turn off your mobile screen when not in use.
  • Reduce the brightness of the screen & set it to adjust automatically.
  • Turn off any keyboard sounds and vibrations.
  • Restrict background apps with high battery use.
  • Turn on battery saver or battery optimization in the system settings.
  • Turn off any unneeded network or wireless connections like Bluetooth or NFC, if you aren't using them.
  • Turn off Location access when not needed.
  • Delete unused apps that are no longer needed.
  • Keep your device operating system and apps updated to make use of the latest features and optimizations.

How to best charge your battery

Best battery charger

Ideally you should only use the original battery charger & USB cable that came with your device or high-quality alternatives that are compatible and comply with the applicable country regulations and safety standards. This is to help prevent against electric damage to the device, battery or other components.

Avoid overcharging and draining the battery

Batteries are under the most stress when they are either fully charged or completely drained. For this reason you should avoid letting the battery drain too low, or keeping it fully charged for too long.

This also means it's best to avoid leaving the battery plugged in to charge overnight, not because it is dangerous (though it can be if you are not using the correct charger) but because having the battery fully charged to 100% and while still connected to the charger (trickle charging) for a long period of time puts strain on the battery and eventually shortens it's lifespan.

Battery optimization

It is best to keep your battery percentage level between 25% to 85% for the optimum balance between battery health and capacity available for your device. This helps prevent stressing the battery and shortening its lifespan.

Ideally when your battery is charging and reaches 85% charge, you should disconnect it from the charger. Once the battery drains to 25% capacity, you should then plug it in to charge again. You can use Charger Alert to notify you when your battery reaches these points help you maintain this charging cycle.

Understandably this isn't always practical if you don't have a charger handy nearby. So this is more of a best-practice guideline than a rule. Going below 25% or above 85% is fine when necessary.

Also it's worth pointing out that this range only provides 60% (85-25) of the battery's capacity to your mobile device. Depending on usage, device, and battery size, this may not be enough to last you the day. In which case you can adjust the numbers, for example 20% to 90% charging range, to suit you.

The main point is to try to avoid draining your battery to near zero or keeping it fully charged for too long.

If you plan to store away a mobile device without using it for a long period, then it's best to leave the battery percentage level (or State of Charge) at around 40% to 60% charge before storage.

Battery calibration

The only time you should purposely drain the battery to 0% and then fully charge it to 100% is if you need to try to re-calibrate the battery. This is where the battery percentage reported is inaccurate and may need re-calibrating.

But this is rare and should not be done regularly. It is often not required, as the hardware and software on the device is able to calibrate the battery during normal use.

Old mobile battery technologies based on nickel like Ni-MH and Ni-Cd had the so-called "memory effect" that required regular battery calibration but newer lithium-ion batteries do not.

Fast charging

Fast chargers provide more amps (electrical current) and voltage to a battery in order to charge it more quickly. Most new mobile devices provide fast charging. This is for convenience for when you need to top-up your battery as quickly as possible so that you can use it again.

Unfortunately fast charging provides a bigger strain on the battery than if it were charged more slowly, but this is the trade off between convenience and longevity.

If you don't need your battery charged quickly, then slow charging your device by plugging it into something that provides a lower current, like your computer's USB port, will charge it at a slower and steadier rate.

At any rate you should avoid any so-called ultra-fast chargers that claim to fully charge Li-ion batteries in less than an hour, as these will quickly shorten the battery life.

Battery temperature: keeping it cool

Batteries get hot when charged fast and when drained fast. When a device is working hard, running intensive apps or games, it requires more power and this energy comes from the battery.

A lithium-ion mobile battery operates optimally between 15 °C to 30 °C. By keeping your battery temperature around this range you will prolong the battery life.

Of course this isn't always possible, because when the device & battery is in heavy use it will inevitable rise to higher temperatures. This isn't a big problem in itself, as long as the battery doesn't stay at those high temperatures for extended periods of time.

If you notice your device is getting hot or the battery is overheating (for example using Charger Alert's battery hot alert) you can maybe give the device a break from use and let the battery temperature return to normal, or find out and stop whatever is currently running if you aren't actively using it.

Restarting the device for a fresh clean start is another option, if you can't determine what is causing the overheating.

Battery health & capacity

Battery health refers to how well the battery functions compared to it’s design specification. Does it still recharge to full and how long does the battery last when fully charged?

Every battery has a maximum capacity when manufactured. For example, a mobile battery rated at 5000 mAh (milliampere hours ) can power a device drawing 250 milliamps for 20 hours, or a device drawing 500 milliamps for 10 hours.

Overtime, as battery cell performance decays through regular use and discharge-recharge cycles, the capacity diminishes. This is why your mobile phone that used to last you all day on a single charge when it was new, might now only last half a day before you are reaching for a battery charger.


No battery lasts forever, and battery health starts to degrade from the moment it is first charged, but the goal is to make this a very slow process and have a battery life that can last a long time.

With the tips and recommendations provided above, along with apps like Charger Alert to monitor and help you extend your battery health, you can get the most out of your mobile device for many years to come.