It’s hard to make smartphone batteries much bigger without adding size and weight to the phone. And phone makers have largely abandoned removable batteries. So over the past few years we’ve seen a focus on making it easier and faster to charge your phone’s battery.
Wireless charging lets you top off your battery simply by placing your phone on a charging surface, with no wires to fiddle with.
Fast charging, meanwhile, lets you refuel your battery without tethering yourself to a charger for too long. How long it too long? That’s probably a matter of user preference, but over the past few years we’ve seen fast charging tech get faster and faster.
Last year Oppo released a “Super VOOC” charger that could take a phone with a 3,400 mAh battery from zero to 100 percent charged in 35 minutes. Now rival Xiaomi is showing off a system that can charge a phone with a bigger battery in just over half the time.
In a demo video posted to Chinese social media site Weibo, Xiaomi president Lin Bin shows its new 100 watt fast charger taking a phone with a 4,000 mAh battery from empty to full in just 17 minutes.
Is that a huge advantage if you normally just plug in your phone before bedtime and unplug it in the morning? Probably not. But if you don’t usually get through a day without stopping to charge your phone once or twice, this means that you could plug in your phone for just a few minutes and probably get enough extra juice to run for hours.
On the down side, the lithium-ion batteries used in smartphones have a limited number of charge cycles. So the more often you charge your phone, the more the battery will degrade — a phone that lasts all day on a charge when you first start using it may die at mid-day after a year or two. Getting in the habit of using your phone heavily and then charging it multiple times a day could theoretically accelerate the process. The good news is that if you eventually need to charge your phone multiple times a day, it won’t take long with a fast charger.
Device makers also have to balance heat generation with charging to ensure that hardware doesn’t overheat. I have to assume Xiaomi has some sort of solution here, or the company wouldn’t be getting ready to launch the new technology.
Xiaomi is expected to reveal more details about its 100 watt fast charging system tomorrow.