Charging your phone at night might seem convenient, but experts suggest doing the opposite. Here’s why switching up your charging habits can be beneficial.
Charging Your Phone: Day vs. Night
Phone manufacturers, including companies like Huawei, recommend charging your phone during the day to help preserve battery life. According to Huawei’s guidelines, leaving your phone connected to the charger for long periods, such as overnight, can be detrimental. They advise against it, emphasizing that battery optimization occurs between 30% and 70%. This means aiming to keep your charge within that range, rather than allowing it to dip below 30% or climb above 70%. While this could mean more frequent charging, your battery’s overall lifespan is likely to improve. Similarly, Apple advises users to keep their battery charge below 80% to optimize longevity.
Understanding Lithium-Ion Battery Power
The science behind lithium-ion batteries can be complex, but here’s a simpler explanation. These batteries function by shifting charge carriers between electrodes, which strains the electrodes and causes wear over time.
Kevin Purdy from iFixIt uses a great metaphor to explain this: Imaging a sponge. It’s easy to fill a sponge from dry to mostly saturated. But getting a nearly saturated sponge to absorb the very last drops requires more pressure and often leaves liquid on the surface. This ‘pooling’ of liquid resembles what happens in a battery with solid electrolytic interface (S.E.I.) buildup, which reduces the battery’s overall capacity.
Moreover, allowing the battery to drain completely to 0% periodically can reduce stress on the electrodes and extend the battery life.
Safety First
There’s also a safety aspect to consider. Charging your phone overnight can increase its temperature, posing a fire hazard. Paul Shaw from Staffordshire Fire Rescue warns that charging your phone under a pillow or on bedding can lead to ‘thermal runaway’ in the battery. This means the battery self-heats and can become dangerously hot, especially if you’re asleep and unaware of the potential danger. It’s safer to charge your phone on a hard surface like a work counter or wooden side table that can handle the battery’s heat output.
The Bottom Line
To prolong your battery’s life, avoid charging your phone for extended periods once it’s fully charged. Many smartphones, like those with iOS13 or later, offer features like Optimized Battery Charging. When enabled, your iPhone will learn your charging habits and delay charging past 80% until you need it.
Additional Tips for Optimizing Battery Life
Besides considering when to charge your phone, there are other ways to extend the time between charges. Here are some tips shared by Samsung:
Use apps that monitor and close background programs when they aren’t in use. Adjust screen brightness or disable auto-brightness. Avoid live backgrounds. Set the screen timeout for a shorter duration. Turn off Wi-Fi and Bluetooth when not in use. Remove unnecessary widgets.
