Published on December 14th, 2019 | by Harry Stoltz0
Moving Beyond Lithium-Ion — A Chat With Leading Battery Researcher Kimberly See
December 14th, 2019 by Harry Stoltz
Professor Kimberly See talks at Caltech’s “Break Through” campaign. Photo courtesy of Chris Flynn for Caltech
Earlier this year, the Nobel Prize in chemistry was awarded for the invention of the lithium-ion battery. This innovation obviously changed and shaped the modern world as we know it. As one might expect, however, there is currently a plethora of research going into the next generation of battery technology. One of the researchers at the cutting edge of this field is Kimberly See, an Assistant Professor of Chemistry at Caltech. I sat down with Kim and had a chat about the exciting things that she and her lab are working on.
Q: What kind of research does the See lab work on?
A: My lab is really interested in the technologies that go beyond lithium-ion battery chemistry. Lithium-ion batteries are a conventional, rechargeable battery system that everyone has in their cell phones and laptops, but they’re reaching their theoretical limitations. They operate on a principle called intercalation chemistry, which of course won the Nobel Prize this year, and we’re all very excited!! The problem with intercalation chemistry is that it operates on a principle that limits its capacity. We’re trying to go beyond that mechanism, and we’re also really interested in materials that are more abundant and less expensive, instead of using things like lithium, cobalt, and nickel.
Professor Goodenough / Photo by: University of Texas at Austin
Q: Professor John B Goodenough and a few other researchers recently won the Nobel prize for the invention of the lithium-ion battery. Why are their contributions so important?
A: Everyone’s been rooting for John to win the Nobel Prize for quite some time. He’s an incredible solid-state chemist, and solid-state physicist. He actually has many contributions to the solid-state chemistry field, including a lot of work in magnetism, so he could have won for that as well. His contribution for intercalation chemistry is his invention of the lithium-cobalt-oxide material that allowed lithium-ion batteries to become commercialized.
Q: What got you interested in battery research?
A: That’s an interesting question, because I remember when I first started battery research, I didn’t realize that it even existed! I think that most people have a perception that batteries are a solved problem, so why is there research in it? When I first started, I had experience in electrochemistry and I also knew that I wanted to learn solid-state chemistry. To me, batteries are the perfect marriage between these two things. It was targeting an energy problem, which is arguably the problem of our time. It checked all the boxes.
Q: I’ve noticed that your lab is working on batteries for a mission to Venus?
A: One of the great things about working at Caltech is our proximity to JPL, so that allows us to pursue some opportunities that we wouldn’t be able to otherwise. They are interested in sending an aerial mission to Venus, because the atmosphere is similar to Earth’s. The goal is to develop a battery powered aerial vehicle that can charge above the clouds with solar and go below the clouds to do its measurements.
Q: How can new battery technology help to combat climate change?
A: I think that batteries are one of the missing pieces for us to go to a renewable grid. If you think about where greenhouse gas emissions are coming from, a lot of it is from power plants, and transportation. Batteries would affect both of those areas. From an energy generation standpoint we would like to move over to things like wind or solar, but those are intermittent, so we would like to be able to store them for longer timescales. Grid storage is huge, but unfortunately our grid isn’t set up for that, so we would also need to upgrade our grid as well. It has to be safe, and it has to be cheap.
Then for transportation, electric vehicles are coming. That’s going to happen. We’re moving to electric vehicles. The question is, will it be a fuel cell car, or will it be a battery car. And I think it’s going to be both, they both have their own benefits. Charging time, of course, is a huge problem for battery cars. Fuel cell cars don’t have that problem. But the generation of the hydrogen is the problem there. Batteries play a central role in pushing things like electric vehicles, which would be hugely beneficial to things like reducing emissions, as long as the energy used to recharge the battery came from a renewable source.
Q: What do you think about a more decentralized energy production system?
A: So this is a microgrid type model. I personally think that it’s going to be hard for people to buy into. I think that sociologically, changing a person’s opinion of what goes into their home is much harder than just talking to a utility and saying “hey, this is cheap, and it’s going to drop the cost of energy,” which is all about economics. But there are people who are installing microgrids at their personal properties. It’s very individual, and for people who have a strong opinion about how their home should run. It’s driven by your kind of interest, and not everybody has that. Their house is hooked up to the grid, and they’re good to go. I think it’s all based on how much people are willing to change, but actually California has this requirement that new home builds need to have solar on their roofs, so you could see that translating into home storage in the future.