{"id":10685,"date":"2016-01-05T11:21:32","date_gmt":"2016-01-05T18:21:32","guid":{"rendered":"http:\/\/cafe.foundation\/blog\/?p=10685"},"modified":"2016-01-05T11:21:32","modified_gmt":"2016-01-05T18:21:32","slug":"deformable-flexible-and-conductive-a-great-solid-electrolyte","status":"publish","type":"post","link":"http:\/\/cafe.foundation\/blog\/deformable-flexible-and-conductive-a-great-solid-electrolyte\/","title":{"rendered":"Deformable Flexible and Conductive \u2013 A Great Solid Electrolyte"},"content":{"rendered":"

Reporting on a new material that doesn\u2019t seem real, a joint research team from Ulsan National Institute of Science and Technology (UNIST) and Seoul National University in Korea<\/a> says it has developed a \u201chighly-conductive, highly deformable, and dry-air-stable glass electrolyte for solid-state lithium-ion batteries.\u00a0 If those characteristics seem mutually exclusive, the electrical performance helps dispel skepticism. \u00a0Assisted by colleagues at Lawrence Berkeley National Lab and Brookhaven National Lab, the researchers prepared the electrolyte using a \u201chomogenous methanol solution,\u201d and wetting exposed surfaces of the electrode active materials with the solidified electrolyte.<\/p>\n

\"Professor<\/a>

Professor Jung and his team at UNIST<\/p><\/div>\n

Eureka Alerts<\/em> quotes Professor Yoon Seok Jung <\/a>\u00a0(UNIST, School of Energy and Chemical Engineering)\u00a0, \u201cThe research team also developed a material for the solid electrolyte by adding the iodized lithium (LiI) to the methanol liquid which is the compound (Li4SnS4) based on tin (Sn). The compound’s ionic conductivity was originally low, but it got increased by getting mixed with LiI. Consequently, by combining two materials together, it became possible to develop the solid electrolyte with high ion conductivity and air stability.\u201dConventional Li batteries use an organic liquid electrolyte which can be \u201ceasily\u2026 gasified or burned.\u201d\u00a0 The solid electrolyte coating is not flammable or toxic, a great safety enhancement considering the scrutiny now being imposed on lithium batteries following Christmas shipments of \u201choverboards\u201d and the recent spectacular meltdown of a Tesla sedan in Norway.<\/p>\n

One factor keeping solid electrolytes from greater use has been their comparative lack of conductivity.\u00a0 Part of this is the lack of contact with electrodes.\u00a0 Professor Jung and Professor Seng M. Oh (Seoul National University)\u00a0developed a way to coat the active materials with the solid electrolyte. This process called the solution-process works by diffusing the powder type of active material in the liquid from melted solid electrolyte and vaporizing the solvent. At a simple level, it\u2019s a bit like a shake-and-bake recipe.<\/p>\n

\"Comparison<\/a>

Comparison between conventional electrolyte and solid electrolyte deposited on electrodes using new system. \u00a0Greater contact area yields greater conductivity<\/p><\/div>\n

 <\/p>\n

GreenCarCongress<\/em><\/a> includes these notes on the process and its possibly impending commercial realization.<\/p>\n

Most efforts on the development of SEs [solid electrolytes] thus far have placed a strong emphasis on the high ionic conductivity of the SEs. However, there is a huge discrepancy between the high ionic conductivities of sulphide SEs and the below-par performance of bulk type ALSBs [all-solid-state lithium batteries], which originates from the limited ionic contact between the active materials and SEs.<\/em><\/p>\n

For example, cold-pressed composite electrodes have exhibited porosities as high as 20%-30%, reflecting poor surface coverage of SEs on the active materials. Therefore, the fabrication of composite electrodes with more intimate ionic contacts should be a prime objective for future development. However, this development has been inhibited by the drawbacks associated with the conventional protocols of synthesizing sulphide SEs, such as solid-state reactions and mechanochemical methods.<\/em><\/p>\n

\"Electrodes<\/a>

Electrodes coated with new solid electrolyte have greater capacity, longevity<\/p><\/div>\n

A newly developed solid electrolyte has the high ion conductivity and no toxicity problem. In addition, the prices of a raw material and a solvent (methanol) are comparatively low. With this technology, commercialization of solid lithium battery will be available sooner than we thought.<\/em><\/p>\n

\u2014Prof. Yoon Seok Jung (UNIST)<\/p>\n

This research was sponsored by Korea\u2019s Ministry of Science, ICT and Future Planning and Ministry of Trade, Industry and Energy.<\/p>\n

Kern Ho Park,\u00a0Dae Yang Oh,\u00a0Young Eun Choi,\u00a0Young Jin Nam,\u00a0Lili Han, Ju-Young Kim,\u00a0Huolin Xin,\u00a0Feng Lin, Seung M. Oh\u00a0and Yoon Seok Jung contributed to the paper, published in the December 22, 2015 Advanced Materials<\/em>.<\/a><\/p>\n