Most batteries are made from lithium ion, and employ carbon as the anode. Other materials perform much better than carbon, and could substantially increase battery capacity. Tin anodes could potentially triple energy density, and silicon anodes might be able to hold 9 times as much charge as carbon. Such advances could lead to tablet computers and laptops that run for days before battery depletion, and to miniature, battery powered UAVs able to remain aloft for up to an hour. In an interview with Sander Olson for Next Big Future, Washington State University Professor Grant Norton discusses how battery technology could dramatically improve within the next several years, and how batteries with 9 times the energy density of current batteries could emerge within a decade.
Question: Your research company has recently made a battery breakthrough. How long have you been working on this battery project?
We have been working on this battery project for a little over a year, but we’ve been studying tin films on a more general level for several years. Tin is a material that stores about 3 times as much charge as conventional carbon anodes, leading to the potential of tripling energy storage.
Question: Most batteries today are lithium-ion batteries. Does lithium-ion represent the best materials combination?
The lithium-ion battery has many beneficial features, but there is room for improvement. This is why researchers are examining new materials. So we have looked into the prospect of replacing carbon in the anode with tin, which could lead to a tripling of energy density. It would still be a lithium-ion battery, but it would have better performance.
Question: So a lithium-ion battery with tin could potentially last 3x as long as conventional batteries employing carbon?
They should be able hold 3x as much charge. But there are other materials, such as silicon, which could take the performance beyond that of tin. Replacing carbon with silicon should lead to 9x better energy storage.
Question: Would lithium-ion batteries using silicon be substantially more expensive than either carbon or tin?
Yes, at least initially. The challenge of silicon would be making these nanostructured materials, which would be quite difficult with current technology. So using presently available fabrication methods, the current cost would be significantly greater than either carbon or tin.
Question: How quickly can the costs of silicon batteries be brought down?
It is impossible for me to answer that question precisely, but growing silicon nanowires is difficult. I have, however, done research on tin, and the evidence suggests that tin anodes would actually be less-expensive than carbon anode for lithium-ion batteries. So these batteries should store nearly 3x as much and still cost the same, or maybe even less.
Question: Are there any corporations looking to make lithium-ion batteries with silicon anodes?
There are research labs who are using silicon as anodes. Silicon will definitely be a competitor down the road, when costs can be sufficiently reduced. But there are numerous technical issues that need to be surmounted in order to cost-effectively mass-produce silicon anodes. So that is probably a decade or more away. But a 9x improvement over commercial batteries is clearly worth investigating.
Question: Could this tin battery could be scaled up to work in an electric car?
Yes, the manufacturer of the battery wouldn’t need to do anything except replace the carbon anode with our tin anode. So it should be able to replace any lithium-ion battery that uses carbon. It should be noted, however, that even a lithium-ion battery employing tin would not hold as much energy as a gasoline engine.
Question: How does this technology compare to fuel cells?
Since there are multiple versions of fuel cells out there, a direct comparison is difficult. In many applications, particularly where high energy-densities are needed, they are superior to batteries. There are non-trivial cost issues with fuel cells, and so I hesitate to say unequivocally that they are superior.
Question: How long before the first batteries lithium-ion batteries incorporating tin are commercialized?
We are hoping to have something on the market as early as next year. This would not require many changes – it would be a simple switch out. We should be able to produce this at a lower cost than carbon, so we might be able to offer superior performance at a lower cost.
Question: Have you formed any startup corporations to commercialize this?
We are having discussions about the best way to move this into industry. We may want to form a company, or it may be better to find a large partner such as a battery company. But one way or another, this technology should go into mass production soon.
Question: Has funding for battery technology increased during the past decade?
The Obama administration has invested heavily in battery technology. The explosion in mobile electronics over the past decade has been another major driver of R&D funds. Most people are putting their money into lithium-ion battery technology, since that offers substantial performance improvements while leveraging an existing infrastructure.
Question: Are silicon batteries with 9x performance over current carbon batteries feasible within a decade?
I believe it is feasible. Within a decade, we could have batteries that offer 9x performance and longer lifetimes than current lithium-ion carbon batteries. So many of our clean energy initiatives absolutely depend on superior battery technology than we have now. If the 21st century is to be the century of “green power”, then we will need to develop much better battery technology than we have now.