Battery Life: Practical Dos and Don’ts

Updated 5 November 2026 · Standard formula, shown below

To get better battery life, reduce the energy your device uses between charges: dim the screen, limit power-hungry apps and connections, and use built-in power-saving settings when needed. Avoid extreme heat, unnecessary full discharges, and habits such as leaving a device hot in direct sun; these can affect battery health as well as how long a charge lasts.

Battery life versus battery health

“Battery life” can mean two different things. Runtime is how long a device operates on its current charge. Battery health is the battery’s ability to store energy compared with when it was new. A setting that reduces screen or network use may extend today’s runtime, but it does not restore worn battery capacity.

Most phones, tablets, laptops, and wireless accessories use rechargeable lithium-ion batteries. Their usable capacity gradually declines with age, use, temperature, and charging history. The rate varies by battery design and how the device is used, so there is no single number of years or charging cycles that applies to every product.

Do these things to stretch a charge

Lower screen brightness. The display can be a major power consumer, particularly when it is bright or on for long periods. Use automatic brightness if it suits your environment, or lower the level manually.
Shorten screen timeout. Set the screen to turn off sooner when idle. On a laptop, also use sleep or hibernate when you will not be working for a while.
Check battery-usage details. Device settings often show which apps and functions used the most energy recently. If an app is unexpectedly active in the background, restrict its background activity or notifications if you do not need them.
Use power-saving mode strategically. Battery saver settings commonly reduce background work, visual effects, or performance. They are useful when you need more runtime, though some updates, syncing, or notifications may be delayed.
Choose a stronger connection when reception is poor. A device may use more power trying to maintain a weak cellular signal. If you do not need mobile service and have no reliable signal, airplane mode can help; turn Wi-Fi or Bluetooth back on individually if you still need them.
Keep software and apps reasonably current. Updates can include efficiency improvements or fixes for abnormal battery drain. Install them when practical, while recognizing that a device may use extra power temporarily after an update as it completes background tasks.
Use the right charger and cable. Follow the device maker’s charging guidance and use compatible, undamaged equipment. Faster charging is convenient, but charging speed alone does not determine how quickly a battery ages; heat and the device’s charging controls matter too.

Don’ts that waste power or stress a battery

Do not leave a device in extreme heat. A hot car, direct sun, or blocked ventilation can raise battery temperature. Heat is especially worth avoiding while charging or running demanding apps.
Do not force-close every app repeatedly. On many modern systems, inactive apps are suspended, and reopening them can use extra energy. Close an app if it is frozen, malfunctioning, or clearly consuming power in the background—not simply because it appears in the app switcher.
Do not keep unnecessary radios and services active. GPS use, hotspot operation, searching for networks, and some connected accessories can draw power. Turn them off when you are not using them, but do not expect a dramatic improvement if they were not consuming much in the first place.
Do not rely on repeated shutdowns or battery “cleaner” apps. Routine restarts do not increase the battery’s capacity. Be cautious of apps that promise large battery gains without identifying a real source of consumption.
Do not make a habit of draining the battery to zero. Lithium-ion batteries do not need periodic full discharge to “calibrate” them. Charge when convenient; occasional low-battery shutdowns are not a reason to panic, but deliberately repeating them is unnecessary.

Charging habits and long-term health

You generally do not need to wait until a battery is nearly empty before charging, nor do you need to charge it to 100% every time. Partial top-ups are normal. If your device offers optimized charging, a charge limit, or a feature that learns your routine, those options may reduce the time it spends fully charged. Their names and exact behavior differ by device.

Leaving a modern device plugged in does not usually mean it continuously forces current into a full battery: charging systems manage the process. Still, long periods at a full charge combined with elevated temperature can put more stress on a lithium-ion battery. If a laptop is plugged in most of the time, check whether its built-in battery-care settings offer a charge limit. Avoid covering a device or placing it somewhere hot while it charges.

Charging may slow or pause when a device gets too warm or cold, as a protective measure. Let it return to a moderate temperature rather than trying to cool or heat it rapidly. Do not use a swollen, leaking, punctured, or unusually hot battery; stop charging it and follow the manufacturer’s service or recycling instructions.

Find the cause of sudden battery drain

A sharp change in runtime is not always a failing battery. A new app, system update, weak signal, high screen brightness, location use, or background syncing may explain it. Compare battery-usage reports over more than a brief period, since one day of navigation, video calls, or travel can be unrepresentative.

Look at the built-in battery-usage screen and note apps or system functions using an unusually large share.
Check whether the device is warm while idle, whether reception is poor, and whether a feature such as hotspot or location access is active.
Update or remove an app that repeatedly behaves abnormally, and adjust its background permissions if appropriate.
Restart the device if the drain began suddenly or an app appears stuck, then monitor usage again.
If runtime remains poor, check the device’s battery-health information, if available, and contact an authorized service provider about evaluation or replacement.

Battery percentages are estimates, not precise measurements of remaining operating time. The same percentage can last much longer during reading than during gaming, video recording, or navigation. Age-related capacity loss is more likely when runtime has gradually shortened over months or years than when it changes overnight.

What matters most in everyday use

For a phone, start with the display, background activity, and cellular reception. For a laptop, screen brightness, demanding workloads, and sleep settings are often useful places to investigate. Video streaming, gaming, camera recording, navigation, and hotspot use can all raise consumption because they combine several active components.

There is no need to switch off every convenient feature all day. Instead, match settings to the situation: use low-power mode during a long trip, download media over Wi-Fi before travel if that suits your plan, and turn off a hotspot when finished. If your device’s battery is worn, power-saving adjustments can help it last longer between charges, but only service or battery replacement can address lost capacity.

Frequently Asked Questions

Should I charge my phone overnight?
Most modern devices manage charging automatically, so overnight charging is generally supported. Keep the device and charger in a cool, ventilated place, use compatible equipment, and enable optimized charging or a charge limit if your device offers one.

Does charging to 100% damage the battery?
A full charge is not an immediate problem. However, spending long periods fully charged, especially in heat, can add stress over time. A charge limit or optimized charging feature may help if you rarely need a full charge.

Does dark mode save battery?
It can save power on devices with OLED displays, particularly when much of the screen is black or very dark. The effect is smaller or absent on many LCD screens, so dark mode is not a guaranteed battery-life fix.

Should I close apps to save battery?
Usually not as a routine. Modern devices typically suspend apps that are not in use. Close an app if it is frozen or showing unusual background use; repeatedly closing and reopening normal apps can be counterproductive.

Why does my battery drain faster in cold weather?
Cold temperatures can temporarily reduce a lithium-ion battery’s available performance, making the charge appear to fall faster or causing a device to shut down. Let the device warm gradually to a comfortable room temperature; avoid direct heaters.

When should I replace a battery?
Consider an assessment when runtime has become inconvenient despite reasonable settings, the device reports substantially reduced capacity, or it shuts down unexpectedly. A swollen, damaged, leaking, or unusually hot battery needs prompt attention rather than continued use.

Method: the standard formula for this calculation, rounded as each result states. See how the calculators work or report an error.