Researchers led by a team from China’s Ningbo Institute of Materials Technology and Engineering have developed stable solid-state lithium batteries with high energy and power densities.

In “High-Energy All-Solid-State Lithium Batteries with Ultralong Cycle Life,” published in Nano Letters, the scientists explain how they developed a new interfacial architecture. They say that their design approach can be used as a route for synthesizing other sulfur-based or transitional metal electrolyte composites for all-solid-state lithium batteries.

“The energy density for the all-solid-state lithium battery using LiCoO₂ as a positive material has reached a level comparable to that of the liquid one,” write Yao and colleagues. “However, it is still far from meeting the demand for electric vehicle applications due to its theoretical specific capacity limitation. Moreover, power density and cycling stability remain an obstacle for an all-solid-state lithium battery to be practically applied, owing to a large interfacial resistance between the cathode and sulfide electrolyte.

“This issue can be somewhat alleviated by introducing an electron-insulating and ion-conducting material as a functional buffer layer at the active material and sulfide electrolyte interface.

“In this work, a novel interfacial architecture, ∼10 nm Li₇P₃S₁₁ electrolyte particles anchored on cobalt sulfide nanosheets, is achieved by an in situ liquid-phase approach. The unique structure endows an intimate contact interface and uniform volume changes of cobalt sulfide nanosheets, leading to an ultrastable all-solid-state lithium battery with excellent rate capability and cycling stability.”

Source: Green Car Congress