Tired of recharging? New aluminum battery fills up in under a minute. (+video)
The Stanford battery is made from aluminum and graphite, and promises to be safer and more useful than today's lithium-ion batteries.
Smart phones have gotten consistently thinner and faster over the past decade, but their battery life remains stubbornly constant. Most high-end smart phones last for just about a day of normal use, and those that exceed that (such as the Sony Xperia Z3 and the Nokia Lumia 1520) achieve their long life by employing larger, heavier batteries than can hold additional juice.
The reason your current smart phone’s battery doesn’t last appreciably longer than the battery in the original iPhone is that increases in battery efficiency are canceled out by bigger screens, faster processors, and zippier connections. All those electronics draw more power, which means battery life tends to stay about the same.
Now, a team of researchers at Stanford University says it has created an aluminum-ion battery that could alleviate these issues by allowing you to charge your phone in just a minute. Your phone might not last longer without charging, but that hardly matters when you can plug it in and go from zero to 100 percent in 60 seconds.
According to the team, the aluminum-ion battery prototype is better than today’s lithium-ion batteries in a few ways. In addition to allowing super-fast charging, it’s also flexible, so it could be bent to fit tightly inside a smart phone body. The battery is also safer than today’s batteries. Lithium-ion cells can catch fire under certain circumstances, whereas the Stanford team’s prototype can be beaten around or even have a hole drilled through it without safety issues. The Stanford video posted above shows the battery powering an LED light and a smart phone, and continuing to deliver power as researchers bend it and drill a hole through it.
Researchers have been investigating aluminum-ion technology for several years, but haven’t been able to produce a battery that can produce a high enough voltage to power a smart phone. The Stanford team solved that problem by using an aluminum anode and a graphite cathode. Their prototype produces about two volts, even after thousands of cycles of discharging and recharging, and the team believes that improving the cathode could increase the battery’s voltage even further. Today’s smart phone batteries usually produce a voltage of 3.7 volts or 4.2 volts.
The battery isn’t ready for mass production yet. In addition to upping the voltage, the Stanford team also wants to improve its energy density to allow it to store more power per square inch. But the prototype promises to be safer, more flexible, and much more quickly rechargeable than today’s lithium-ion batteries, without being too expensive for practical use.