News

News

New computational screening approach identifies potential solid-state electrolytes

Date: 2020-01-22
Views: 243

Replacing the volatile and flammable liquid or polymer electrolytes now used in lithium-ion batteries with inorganic solid-state lithium-ionic ceramic conductors could significantly improve both safety and performance of the cells. Solid-state conductors would allow for novel cathode and anode chemistry, prevent the growth of Li-metal dendrites and push miniaturization.


Though researchers have investigated several structural families of promising solid-state Li-ion conductors over the past decades, the fact that there are many desired properties--including fast-ionic/superionic diffusion of Li ions, very low electronic mobility, wide electrochemical stability windows, and high mechanical stability--means that no one material has emerged as an ideal candidate for development and so the search continues.


Previous research has been largely led by chemical intuition and carried out through immediate experimental investigation. Synthesizing ionic compounds and measuring ionic conductivity are labor intensive tasks though and experimental results can be difficult to interpret. Computational methods, on the other hand, are easy to automate and run in parallel. That is, they can efficiently identify materials that merit the hassle and expense of experimental investigation in the search for new solid-state electrolytes.


Current approaches to computational screening rely on simulations of the electronic structure to determine the insulating character of a material and on molecular dynamics simulations to predict the Li-ion diffusion coefficients. This means running thousands of calculations and so automation and reproducibility are essential. Computational methods need to be inexpensive enough to be run for thousands of materials, yet accurate enough to be predictive. In the paper High-throughput computational screening for solid-state Li-ion conductors, the researchers present a new framework that meets these requirements. Screening compounds through several stages of computational filter, they probe new structural families for promising Li-ionic conductors in a cost-effective, accurate way.


The new approach was used to screen two repositories of experimental structures, the ICSD and COD, which describe some 1,400 unique crystal structures between them. After identifying electronically insulating systems, the scientists used their recently introduced pinball model -- a framework that is based on physical observations of how electrons behave in an ionic system and which greatly simplifies the modeling of ionic conductors--to identify materials likely to display fast-ionic diffusion. Some 115 identified structures were then simulated with accurate first-principles molecular dynamics for a total of 45 nanoseconds at high and intermediate temperatures.


The approach resulted in the identification of five materials with fast ionic diffusion--some in the range of the well-known superionic conductor Li10GeP2S12--as well as 40 materials that at least showed significant diffusion at 1000 K. Though it is not possible to say whether these latter materials can be considered fast-ion conductors at lower temperatures because of the short time scales of the study, they are promising for more detailed study.


The authors expect the data, new methods and analysis techniques described in the paper to be useful in the ongoing search for novel descriptors of fast Li-ion diffusion in the solid state. 


Via: https://www.chemeurope.com

Note: Content may be edited for style and length.




News / Recommended news More
2020 - 07 - 02
A Bochum-based team has developed a new process for zinc oxide layers that can be used for nitrogen oxide sensors as well as protection layer on plastic.The application of zinc oxide layers in industry is manifold and ranges from the protection of degradable goods to the detection of toxic nitrogen oxide gas. Such layers can be deposited by atomic layer deposition (ALD) which employs typically che...
2020 - 07 - 02
Grain boundaries in ceramics may not be as chemically stable as previously thought. So say researchers at the University of Wisconsin-Madison in the US who have found that carbon atoms collect or segregate at the boundaries of silicon carbide – a technologically important ceramic – when the material is exposed to ionizing radiation. The result could help improve our understanding of ceramics in ge...
2020 - 06 - 24
Waste heat is all around you. On a small scale, if your phone or laptop feels warm, that's because some of the energy powering the device is being transformed into unwanted heat.On a larger scale, electric grids, such as high power lines, lose over 5% of their energy in the process of transmission. In an electric power industry that generated more than US$400 billion in 2018, that's a tremendous a...
2020 - 06 - 17
When most people think of ceramics, they might envision their favorite mug or a flowerpot. But modern technology is full of advanced ceramics, from silicon solar panels to ceramic superconductors and biomedical implants.Many of those advanced polycrystalline ceramics are combinations of crystalline grains which, at the microscopic level, resemble a stone fence held together with limestone mortar. ...
Share:
Uniris Exhibition Shanghai Co., Ltd.
Shanghai Branch
Tel: 4000 778 909 
E-mail:irisexpo@163.com

Guangzhou Branch
Tel: 020-8327 6389
E-mail:iacechina@unifair.com

IACE CHINA Official Website
犀牛云提供企业云服务
犀牛云提供云计算服务
Scan