Future Batteries Could Have Six Times More Capacity

By Tom Pritchard on at

It's no secret that human beings have a serious battery addiction, and the ones we have right now aren't going to cut it forever. Fortunately there are teams of researchers tirelessly working to improve battery technology all over the world, and one of those teams thinks it's onto something.

The team, from the HZB Institute for Soft Matter and Functional Materials in Grenoble, has been looking into the graphite electrode that's present in every lithium ion battery. Graphite is often used because it's cheap, stable, and won't be running out anytime soon. The downside is that each electrode can only adsorb a set number of ions before hitting capacity.

The team has been trying to replace the graphite with silicon, another substance that's cheap, holds more ions than graphite, and can be found basically everywhere. In the past silicon has been problematic because ions tend to disrupt its crystalline structure, causing the electrode to swell up by a factor of three. The HZB team may have found a solution, after discovering that most ions stay in the top 20 nanometres of the electrode. In fact, only a measly 26 ions got any deeper.

So by using multiple thin silicon films, it should be possible to create batteries that have a much higher capacity. Using thinner film means that the silicon swelling will be much easier to deal with, and obviously silicon itself can hold a lot more juice than boring old graphite. The maths indicates that by using this configuration, we should be able to squeeze in six times more power into our batteries.

Whether we'll ever see this tech included in our smartphones is another thing entirely. There are going to have to be rigorous tests to make sure that batteries using silicon film electrodes are stable and safe enough for general use. Then, obviously, the manufacturing process is going to have to be cost-effective, or else they'll never see the light of day. [ACS Nano via TechRadar]