Samsung Presents Groundbreaking Lithium Metal Solid-State Battery

March 12, 2020 by Paul Shepard

Researchers from the Samsung Advanced Institute of Technology (SAIT) and the Samsung R&D Institute Japan (SRJ) presented a study on high-performance, long-lasting solid-state batteries in Nature Energy. The prototype pouch cell battery can be cycled 1,000 times with an energy density >900Wh/L.

This promising research is expected to help drive the expansion of electric vehicles (EVs). The prototype cell that the team developed would enable an EV to travel up to 800km on a single charge.

In the abstract to the Nature Energy article, the researchers state: "An all-solid-state battery with a lithium metal anode is a strong candidate for surpassing conventional lithium-ion battery capabilities. However, undesirable Li dendrite growth and low Coulombic efficiency impede their practical application. Here we report that a high-performance all-solid-state lithium metal battery with a sulfide electrolyte is enabled by a Ag-C [silver-carbon] composite anode with no excess Li. We show that the thin Ag-C layer can effectively regulate Li deposition, which leads to a genuinely long electrochemical cyclability.

Recommended for you: BioSolar Completes Silicon Anode Lithium-ion Battery Prototypes

"In our full-cell demonstrations, we employed a high-Ni layered oxide cathode with a high specific capacity (>210 mAh/g) and high areal capacity (>6.8 mAh/cm2) and an argyrodite-type sulfide electrolyte. A warm isostatic pressing technique was also introduced to improve the contact between the electrode and the electrolyte. A prototype pouch cell (0.6Ah) thus prepared exhibited a high energy density (>900 Wh/L), stable Coulombic efficiency over 99.8% and long cycle life (1,000 times)."

(From left) Yuichi Aihara, Principal Engineer from SRJ, Yong-Gun Lee, Principal Researcher and Dongmin Im, Master from SAIT.

Compared to widely used lithium-ion batteries, which utilize liquid electrolytes, all-solid-state batteries support greater energy density, which opens the door for larger capacities, and utilize solid electrolytes, which are demonstrably safer. However, the lithium metal anodes that are frequently used in all-solid-state batteries, are prone to trigger the growth of dendrites which can produce undesirable side effects that reduce a battery's lifespan and safety.

To overcome those effects, Samsung's researchers proposed utilizing, for the first time, a silver-carbon (Ag-C) composite layer as the anode. The team found that incorporating an Ag-C layer into a prototype pouch cell enabled the battery to support a larger capacity, a longer cycle life, and enhanced its overall safety. Measuring just 5µm (micrometers) thick, the ultrathin Ag-C nanocomposite layer allowed the team to reduce anode thickness and increase energy density up to 900Wh/L. It also enabled them to make their prototype approximately 50 percent smaller by volume than a conventional lithium-ion battery.

As Dongmin Im, Master at SAIT's Next Generation Battery Lab and the leader of the project explained, "The product of this study could be a seed technology for safer, high-performance batteries of the future. Going forward, we will continue to develop and refine all-solid-state battery materials and manufacturing technologies to help take EV battery innovation to the next level."

Nature Energy Publication

High-energy long-cycling all-solid-state lithium metal batteries enabled by silver-carbon composite anodes, Yong-Gun Lee, Satoshi Fujiki, Changhoon Jung, Naoki Suzuki, Nobuyoshi Yashiro, Ryo Omoda, Dong-Su Ko, Tomoyuki Shiratsuchi, Toshinori Sugimoto, Saebom Ryu, Jun Hwan Ku, Taku Watanabe, Youngsin Park, Yuichi Aihara, Dongmin Im & In Taek Han.