Fresh research out of Arizona State University has pushed the institution closer to the development of lithium-metal batteries, which are widely regarded as the most promising candidates for high-density energy storage of the future.
Previously, studies into lithium-metal batteries had shown that they are held back by uncontrolled lithium dendrite growth, which results in poor recharging capability and safety hazards, tempering their potential.
Dendrites, which are needle-like growths that appear on the surface of lithium metal, are used as the anode, or negative electrode, of a battery. They induce unwanted side reactions that reduce energy density, and can cause shorting of the electrodes that can lead to fires or explosions if not integrated properly.
However, the latest findings by the Arizona State University show that by involving a three-dimensional layer of Polydimethylsiloxane (PDMS), or silicone, as the substrate, lithium metal anode can mitigate dendrite formation and stands to both dramatically extend battery life and diminish safety risks.
According to the University’s professor of School for Engineering of Matter, Transport and Energy, and lead on the research paper, Hanqing Jiang, the findings have relevance for both lithium-ion and lithium-air batteries, as well as implications for other metal-anode-based batteries.
“Almost all metals used as battery anodes tend to develop dendrites,” explained Jiang. “For example, these findings have implications for zinc, sodium and aluminum batteries as well.”
He added that he and his research team didn’t approach the problem from a materials or electrochemical perspective, but instead looked for solutions as mechanical engineers.
“We already know that tiny tin needles or whiskers can protrude out of tin surfaces under stress, so by analogy we looked at the possibility of stress as a factor in lithium dendrite growth.”
By combining with other lithium dendrite suppression methods, such as new electrolyte additives, the researchers found that the material has implications for making lithium-metal batteries a safe, high-density, long-term energy storage solution
“Potential applications range from personal electronic devices to powering electric cars for exceptionally longer periods to being the back-up electric supply for solar power grids,” added Professor Ming Tang, a research team member at Rice University.