For many of us, the overnight period is a convenient opportunity to let your phone recuperate the battery it has lost from the day before. For those six or more hours of uninterrupted sleep, what percentage your phone is on has no impact on your life and you can leave the device alone knowing that when you wake up you’ll have a full charge to use.
Yet, as you may have read in the past there are some people who claim that charging your phone overnight can overload the battery – presenting a potential fire risk to users. This post will help you understand if leaving your phone on charge and unattended can be dangerous and if you should take precautions.
How high is the fire risk?
While it’s not completely unheard of for phones to catch fire due to battery problems, these are normally due to a problem with the range of devices having common issues. Unless your smartphone has some serious manufacturing defects the chances of your phone catching fire due to being left on charge is extremely unlikely.
Problems can occur, however, if you take the phone into bed with you and it gets covered by your duvet or pillow. This is due to the amount of heat the device generates from an overnight, slow charge. If you have an iPhone, you may have already seen that Apple has introduced a new feature for people who charge their phone overnight – telling you exactly when the charge is expected to finish so that your battery charges slowly and in a controlled manner – stopping once it hits 100% of its capacity.
Apple also warns on its website, the batteries used in iPhones can be degraded by extreme heat — though that’s something to watch out for regardless of when you recharge your device.
One easy way to reduce your risk of your battery overheating and getting a burn, (other than to avoid stacking objects on the phone) is to take your phone out of its protective cover when leaving it to charge overnight. Although this is not always feasible, it can significantly reduce the chance of the battery becoming damaged by getting extremely hot.
Can the battery be damaged from trickle charges?
Your battery should last for as long as you have the smartphone, because phone batteries measure their lifespans in charge cycles, not years. The cycle count is the number of full charges a smartphone can deal with before its battery is significantly degraded. For instance, if you drain a phone’s battery halfway then recharge that half-empty capacity, that takes up half a cycle. A typical smartphone battery will get about 400 charge cycles, which should help the device last at least a year and a half.
Smartphone batteries are in a constant state of decay which means leaving your phone in the charger overnight, even when it’s fully charged, won’t do much to change its overall lifespan, which will be degrading with use anyway. Sleeping with a phone charging overnight will make no noticeable difference to this process.
The idea that charging overnight may be harmful — or cause mini-charges that continuously drain the battery, typically comes from people’s experiences with older laptops, which did use to suffer from this problem.
Is it better for battery life to wait till the battery reaches 0% before charging?
While early cell phones had nickel-cadmium batteries, which did perform better if you let them empty before recharging them, today’s smartphones use lithium-ion batteries, which are okay to charge no matter the percentage of unused power left.
To get the best out of your charge you should also use the brands own charging cord and plug that came with your phone whenever possible. This is because these chargers are made according to the standards in place to charge your phone using the correct voltage. An off-brand charger or cord can damage the charger port in your phone and, by extension, the battery.
If you’re having problems with your battery, don’t forget you can take your phone back to the supplier for a new one for a small fee, or alternatively, it might be time to upgrade your phone. Let us know in the comments section, or @techtroublesho1, if you have any questions or other technology queries.