Engineers from UC San Diego collaborated with researchers in LG Energy Solution to create a high-performance all-solid-state battery with pure silicon anode. This new battery technology could make future electric vehicles cheaper as it uses an all-silicon anode, which offers high energy density, longer life, and fast-charging capabilities.
The new battery technology is described in the study, titled "Carbon-Free High-Loading Silicon Anodes Enabled by Sulfide Solid Electrolytes," published in the recent issue of the journal Science.
Using Silicon Anodes in Replacement of Graphite
The silicon all-solid-state battery uses both a solid-state electrolyte and an all-silicon anode. According to Android Headlines, initial rounds of tests on the new battery technology showed that it is safe, long-lasting, and offers high energy density.
Graphite anodes are used in making batteries, but silicon anodes are more preferred to use today in lithium-ion batteries because they have ten times greater energy density. However, they degrade quickly with liquid electrolytes, so all-silicon anodes are not used in commercial lithium-ion batteries.
But the new technology promises a path towards using all-silicon anodes using solid electrolytes in place of liquid electrolytes. Study lead author Darren H.S. Tan said that this new battery technology opens a new territory for solid-state batteries using silicon anodes.
Next-generation solid-state batteries use metallic lithium anodes that require 140 degrees Fahrenheit (60 degrees Celsius) during charging, but this means that they are impractical in colder climates. On the other hand, silicon anodes overcome this limitation y maintaining high energy density and allowing faster charging at room temperature.
Creating the Solid-State Battery
UC San Diego News Center reported that the team eliminated the carbon and the binders found in silicon anodes and used micro-silicon that is less expensive and less processed than nano-silicon. Additionally, they used sulfide-based solid electrolytes instead of liquid electrolytes.
This helped researchers avoid a series of challenges when anodes are soaked in organic liquid electrolytes as batteries function. Also, it significantly reduced the interfacial contact and side-effects with the solid electrolyte to prevent capacity loss that usually happens in liquid-based electrolytes.
This showed that batteries that use all-silicon anodes have extremely stable solid electrolytes that can retain 80% capacity even after 500 charge and discharge cycles at room temperature.
New Battery Technology Could Revolutionize Electric Vehicles
"The solid-state silicon approach overcomes many limitations in conventional batteries. It presents exciting opportunities for us to meet market demands for higher volumetric energy, lowered costs, and safer batteries especially for grid energy storage," Tan said in the news release.
Tan, who is UNIGRID Battery's CEO and co-founder, has licensed the new battery technology. The team has found an excellent opportunity of using these sulfide-based solid electrolytes to create a highly stable anode and utilize it in commercial batteries.
Researchers said that the all-solid-state battery could revolutionize electric vehicle production and make it cheaper. Myung-hwan Kim, Chief Procurement Officer from LG Energy Solution, said that they would continue expanding this research with the team from UC San Diego to foster state-of-the-art techniques in leading the research for next-generation battery cells.
Check out more news and information on Battery on Science Times.