Breakthrough in All-Solid-State Lithium Batteries A New Homogenized Cathode Material
TapTechNews July 31st news, all-solid-state lithium batteries with non-flammable inorganic solid electrolytes can meet the growing demand for high-safety energy storage systems.
All-solid-state lithium batteries usually adopt a composite electrode that includes electrode active materials, electron-conducting and ion-conducting auxiliaries. There are various interface problems induced due to the difficulty in perfect matching among different components in terms of chemical, electrochemical, and mechanical properties, seriously deteriorating the energy density and service life of the battery.
In this regard, under the leadership of researcher Cui Guanglei from the Solid State Energy System Technology Center of the Qingdao Institute of Bioenergy and Process Technology, Chinese Academy of Sciences, Ju Jiangwei, Cui Longfei, Dr. Zhang Shu, etc. pioneered the design of a new homogenized cathode material - Li1.75Ti2(Ge0.25P0.75S3.8Se0.2)3, which has both high ionic conductivity (0.2 mS cm−1), high electronic conductivity (225 mS cm−1), and high discharge specific capacity (250 mAh g−1).
Compared with traditional materials, this material has the advantages of high conductivity, high energy density, and long service life, subverting the paradigm of the all-solid-state lithium battery composite cathode and fundamentally solving the above problems,制备出兼具高能量密度和长循环寿命的全固态锂电池。
This breakthrough is expected to make the dream of miniaturization and long battery life of electronic devices a reality. The relevant research results were published in the international academic journal Nature Energy on July 31 (TapTechNews attaches DOI: 10.1038/s41560-024-01596-6).
The ionic and electronic conductivity of this material is more than 1000 times higher than that of traditional layered oxide cathode materials, and the specific capacity exceeds that of current high-nickel cathode materials. At the same time, this material only undergoes a volume deformation of 1.2% during the charge and discharge process, which is lower than 50% of the traditional layered oxide cathode materials.
The high conductivity can ensure the normal charge and discharge of the cathode without adding conductive auxiliaries, and the low volume deformation guarantees the stability of the structure of the battery during the charge and discharge process. The all-solid-state lithium battery constructed with 100% active materials maintains 80% of the initial capacity after 5000 cycles, and its high energy density of 390 Wh/kg is 1.3 times that of the currently reported long-cycle all-solid-state lithium battery.
The official pointed out that this research provides technical support for the development of high-energy-density and long-service-life energy storage devices, providing a safe and durable power source for new energy vehicles, energy storage grids, deep-sea and deep-space equipment, etc., and has important significance for the development of new energy storage systems.