Graphene-based nanosheets give lithium-ion batteries more energy storage

Modern lives are ruled by mobile devices, from smartphones and tablets, to portable gaming systems and e-readers. Considering these devices need some kind of power source, this means that batteries are what actually have dominion over our daily activities. Battery tech hasn't improved at the rate of the hardware it powers, but the industry has been taking baby steps. Now, Chinese scientists have taken a new baby step that could help batteries store more power.

The two main areas of battery technology that need improvement are how quickly they can deliver an amount of power to a device, and how much energy it can store. In the lithium-ion consumer market, a larger battery usually means more space in which to store energy, but lithium-ion falls prey to a low theoretical capacity compared to newer, less explored battery tech. In order to increase the capacity of a lithium-ion battery without drastically increasing the battery's physical size, nanostructured electrodes can hold more lithium ions, and thus provide more capacity for energy storage. However, these flimsier electrodes become damaged due to pulverization, which refers to the swelling from a battery's charge-discharge cycles. If the electrodes were able to survive the damage, then the storage capacity of a lithium-ion battery could increase. Using everyone's favorite wonder material, graphene, a team from the University of Science and Technology in China have managed to prevent the issue of pulverization(Opens in a new window).

Using sheets of cobalt oxide that are around one atom thick -- not exactly graphene, but close enough to be considered an analog -- the researchers were able to increase the surface area of storage capacity, as well as easier electron transportation. Unfortunately, a fellow energy storage capacity expert from Graz University of Technology in Austria, Stefan Freunberger, feels that though the Chinese team's approach to increassing battery storage capacity is certainly interesting, it will be difficult to include the technique in a consumer-level device. However, if you ever read about any innovative battery tech, you probably could have assumed that. (See: DoE calls for a chemical battery with 5x capacity, within 5 years – can it be done?)

The new nanosheet strategy is currently in early stages of development; so early, in fact, that the research team has not yet even settled on which materials to use when developing the sheets. Cobalt oxide has proven fruitful, but there are other graphene analogs that the team feels are worth exploring in an attempt to find even greater storage potential. Considering a large swathe of innovative battery tech has moved away from the constraints of lithium-ion, such as the aluminum-air battery, it might seem like the battery tech industry is beginning to feel that the lithium-ion battery has run its course. However, the University of Science and Technology feels that there's more to improve, and perhaps improving a technology with which we're already familiar -- rather than inventing an entirely new tech -- would be the quickest route to getting our phones and tablets to last longer.

Now read: New lithium-ion battery design that’s 2,000 times more powerful, recharges 1,000 times faster