New "Pomegranate" Design a Fix for Lithium-ion Battery Issues
Scientists at Stanford University and the Department of Energy's SLAC National Accelerator Laboratory believe they have solved key issues associated with silicon anodes, which can be used in lithium-ion batteries.
Anodes, which store energy when a battery is charged, are commonly made of graphite, but it's not the only material that can be used. In fact, a more attractive option is silicon. That's largely because silicon anodes, which can be used in lithium-ion batteries, as well as lithium-air and lithium-sulfur batteries, can store up to 10 times as much charge as those made out of graphite, Science World Report explains. However, that's not to say silicon anodes don't have problems. In fact, as Gizmodo's Adam Clark Estes notes, they have two big ones: During charging, silicon swells and, due to its fragility, breaks. Silicon is prone to reacting with batteries' electrolytes, and that can "gunk up the circuits." Now, scientists at Stanford University and the Department of Energy's SLAC National Accelerator Laboratory believe they have found a solution to those issues. Surprisingly, it looks like it was pomegranates — yes, the fruit — that helped them do so. The pomegranate solution In a report published in the journal Nature Nanotechnology, the scientists, led by Yi Cui, an associate professor at Stanford, propose a "hierarchical structured silicon anode ... inspired by the structure of a pomegranate." The design draws on technology that Cui and his team have been working on for the past eight years, according to a press release put out by SLAC. During that time, they devised a way to encase silicon nanoparticles "that are too small to break into even smaller bits" in carbon "yolk shells." Using silicon nanoparticles that are already as small as they can get addresses the silicon anode breakage problem, while putting those nanoparticles in a carbon shell allows enough room for the swelling silicon undergoes when charging.