For Hugh Smith, a fifth-year PhD candidate in MIT’s Department of Materials Science and Engineering, the challenge of building an energy-secure future isn’t about creating the world’s “best” battery. It’s about designing the right battery for the right job. Smith studies sodium-ion batteries, an emerging alternative to the lithium-ion batteries that power everything from smartphones to electric vehicles. By replacing expensive critical minerals like lithium, nickel, and cobalt with more readily available elements like sodium, iron, and manganese, his research aims to make energy storage both more affordable and more sustainable. Smith’s research focuses on finding the right balance for specific applications, often juggling competing priorities. Instead of strengthening a singular characteristic, Smith works to maximize as many components of the battery as possible, including cost, performance, sustainability, and reliability, depending on how it will be used. The sodium-ion batteries Smith studies could eventually provide lower-cost options for electrical grids or more affordable electric vehicles. Because sodium-ion batteries can largely be manufactured using the same infrastructure already developed for lithium-ion batteries, they also offer a potentially smoother path toward commercialization than many emerging battery technologies. Smith’s graduate school journey has been defined as much by the process of learning how to do research as by the science itself. He joined a brand-new research group at MIT as its first graduate student, and helped establish the lab run by Professor Iwnetim Abate. Blogger's Review: Building energy security through more sustainable batteries is a crucial research direction. Smith's work provides new insights and methods for battery technology, and his research outcomes may have a significant impact on energy storage and sustainable development.