'Don't Charge iPhone Overnight' Claim Overblown

Apple has issued a warning about safely charging iPhones. However, reports in which the company said users should never charge their phone while they sleep are incorrect.

At least one newspaper reported the story with the headline "Why you shouldn't charge your iPhone while you sleep." Another site used the slightly more accurate but still potentially misleading "Apple warns people should never sleep next to their phone while its charging."

From those headlines you might think Apple is making a surprisingly open revelation about handsets spontaneously combusting and taking out everything in a six-foot radius. That's absolutely not the case.

Ventilation Is Key

Instead, the statement is simply a warning against charging the phone while it's on the bed, particularly under a blanket or pillow. That's because of the risk that the phone could overheat while charging if it isn't properly ventilated.

Apple goes further, noting that users should "take special care if you have a physical condition that affects your ability to detect heat against the body." It also suggest making sure there's no liquids near to the device while charging, for example a glass of water on a bedside cabinet by the phone. (Source: mirror.co.uk)

It's not clear if any specific incident prompted the statement, or indeed if Apple was intending to get the word out to all users or simply doing a routine update to its guidance. The statement also warns users that if they use third-party cables and power adapters, they should look for the 'Made for iPhone' badge that shows it meets Apple's safety standards. It also suggests checking chargers are compliant with USB standards, with USB 2.0 as a minimum.

Battery Charging Issues

In the past, some users have feared that leaving a phone to charge overnight can damage the battery by "overcharging it". That's not the case with modern lithium-ion batteries which will stop drawing power from a charger once they reach 100% capacity.

Instead the battery will receive a trickle charge, meaning that once the phone's background activities have drained it a little (to 99% or lower), it will then top up to capacity. Keeping the battery at 100% for longer can slightly reduce its lifespan, but not to a significant extent. (Source: wired.co.uk)

What's Your Opinion?

Do you charge your phone overnight? Do you take any steps to reduce the risk of overheating? Are you surprised people need to be told not to sleep with a phone in their bed?