A new study that was led by researchers from the University of Oxford and was published today in Nature suggests that significantly improved batteries for electric vehicles (EVs) may be one step closer. Utilizing advanced imaging strategies, analysts uncovered instruments that cause lithium metal strong state batteries (Li-SSBs) to fizzle. Solid-state batteries with lithium metal anodes have the potential to significantly improve EV battery range, safety, and performance if these obstacles can be overcome. They could also contribute to the development of electrically powered aviation.
One of the co-lead creators of the review, Dominic Melvin, a Ph.D. understudy in the College of Oxford’s Branch of Materials, said, “Advancing strong-state batteries with lithium metal anodes is perhaps the main test confronting the headway of battery advancements. Research into solid-state batteries has the potential to be a high-risk, game-changing technology, even though the current generation of lithium-ion batteries will continue to improve.
Li-SSBs are different from other batteries because they use lithium metal as the anode (negative electrode) and replace conventional batteries’ flammable liquid electrolyte with a solid electrolyte. Safety is enhanced by using a solid electrolyte, and lithium metal makes it possible to store more energy.
“The process by which a soft metal like lithium can penetrate a highly dense hard ceramic electrolyte has proven difficult to understand, with many significant contributions from excellent scientists all over the world. We anticipate that the extra insights gained will aid the advancement of solid-state battery development toward a viable device.”
Sir Peter Bruce, Wolfson Chair, Professor of Materials at the University of Oxford,
However, a significant issue with Li-SSBs is their propensity to short circuit during charging due to the development of “dendrites,” metal lithium filaments that pierce the ceramic electrolyte. As a component of the Faraday Organization’s SOLBAT project, specialists from the College of Oxford’s Divisions of Materials, Science, and Designing Science have driven a progression of inside and outside examinations to see more about how this shortcircuiting occurs.
Dendrite failure was observed in unprecedented detail during the charging process using a cutting-edge imaging method called X-ray computed tomography at Diamond Light Source in this most recent study. The new imaging concentrated on revealing that the inception and proliferation of the dendrite breaks are discrete cycles, driven by unmistakable fundamental components.
When lithium builds up in the pores beneath the surface, dendrite cracks occur. When the pores are full, additional battery charging raises the pressure, which causes the battery to crack. Conversely, engendering happens with lithium, just to some degree, filling the break through a wedge-opening system that drives the air out from the back.
The way forward for overcoming Li-SSB’s technological challenges is indicated by this new understanding. “Our results demonstrate that too much pressure can be detrimental, making dendrite propagation and short-circuiting on charging more likely,” Dominic Melvin stated. “For example, while pressure at the lithium anode can be good to avoid gaps developing at the interface with the solid electrolyte on discharge,”
“The process by which a soft metal such as lithium can penetrate a highly dense, hard ceramic electrolyte has proved challenging to understand, with many important contributions by excellent scientists around the world,” stated Sir Peter Bruce, corresponding author of the study and Professor of Materials at the University of Oxford. We anticipate that the additional insights we have obtained will contribute to the development of a practical device for solid-state battery research.”
By 2040, SSBs could meet 50% of global demand for batteries in consumer electronics, 30% in transportation, and more than 10% in aircraft, according to a recent Faraday Institution report.
“SOLBAT researchers continue to develop a mechanistic understanding of solid-state battery failure—one hurdle that needs to be overcome before high-power batteries with commercially relevant performance could be realized for automotive applications,” stated Professor Pam Thomas, CEO of the Faraday Institution. The project is providing cell manufacturers with strategies for preventing cell failure with this technology. One excellent illustration of the kind of scientific advancements that the Faraday Institution was established to promote is this application-inspired research.”
More information: Peter Bruce, Dendrite initiation and propagation in lithium metal solid-state batteries, Nature (2023). DOI: 10.1038/s41586-023-05970-4. www.nature.com/articles/s41586-023-05970-4
