Mechanical engineer Marm Dixit’s work is all about getting electricity to flow efficiently from one end of a solid-state battery to the other. It’s a high-stakes problem: The future of electric vehicles, among other key green technologies, rides on the ability of him and other scientists and engineers to create high-energy density battery designs that are practical, safe, recyclable and affordable.
A slew of challenges lies between Dixit, a Weinberg Distinguished Staff Fellow at Oak Ridge National Laboratory, and this goal. It’s one thing to experiment with solid anodes, cathodes and electrolytes and get battery designs to work. It’s another to design a battery that can both outperform today’s liquid lithium-ion batteries and, with an eye to industry, be efficiently mass produced.
“Our approach from the beginning has been, ‘Let's try and build something that's practical,’” said Dixit.
This highly competitive research area is hotter than a short-circuited battery, and Dixit and his colleagues in the lab’s Emerging and Solid-State Batteries group have been working hard to overcome the many technical hurdles. These “beasts,” as Dixit calls them, demand novel, creative thinking. Luckily, that’s something this published poet, avid reader, accomplished flautist and clever cutup offers in spades.
Battery startups aplenty
Generally, the lithium-ion batteries in mobile phones, electric cars and laptops have done the job. But they came with a downside: flammable electrolytes that can lead to fires or explosions. Now, after decades of development, the technology seems to have reached a peak, priming the market for a new type of battery to meet the world’s growing demand for low-carbon transportation.
Indeed, solid-state batteries promise to charge quicker, last longer and operate more safely. A commercially successful solid-state battery should have an energy density nearly twice that of lithium-ion, Dixit said. Currently, researchers are reporting performances that are, at best, roughly equal to that.
“Solid-state batteries should improve on current lithium-ion battery,” Dixit said. “Otherwise, there is no point.”
In his crowded field, Dixit said battery startups are plentiful. Many researchers are narrowing in on specific issues, including the various problems that can surface at the electrode–electrolyte interface. For example, dendrites can emerge from metal lithium anodes and, drill-like, penetrate the electrolyte.
“I have a Google Scholar alert for solid-state batteries,” Dixit said. “Every day I'll get 20 papers, and the titles are quite varied.”
For Dixit, who was awarded a Toyota Young Investigator Fellowship for Projects in Green Energy Technology from the Electrochemical Society last year, the focus is to “de-risk” battery designs and shepherd them to the point where industry feels confident running with them.
And with a powerful tool he developed and released in February, Dixit is empowering others in his field to do the same.
A solid idea
He dubbed the tool SolidPAC, short for Solid-State Battery Performance Analyzer and Calculator. Downloadable from the tool’s webpage, the open-source software lets researchers virtually test different battery configurations to see if they’re worth pursuing.