CCPR073 - Discovery of inorganic lithium solid electrolytes for all-solid-state batteries

固体电解质(SE)系统的开发是一个不断增长的领域，因为开发商业上可行的全固态电池(ASSB)的动力越来越大。目前，人们对锂离子电池(LiB)技术的局限性感到担忧，因为与ASSB的假设储能容量相比，锂离子电池的储能能力更高。ASSB开发的一个焦点是最先进的固体电解质的发展。最近，利物浦大学开发了一种新的材料，它利用与金属间化合物系统相当的离子排列来产生一种系统，该系统改善了结构多样性，随后具有高锂离子导电性(Science，2024,383,739-745)。与其他主要的SE体系相比，这种离子排列促进了广泛的阳离子配位环境，提供了较低的能垒和更高的离子导电性。本研究的目的是通过探索可能采用这种结构类型的新的组成和材料来扩展这种新的结构化学。这涉及到阳离子和阴离子物种的多样化。假设是，进一步增加无序度将改善这个系统已经令人印象深刻的离子传导性。此外，已知的金属间结构基元和离子导体之间的关系将进一步探索，以确定其他有利于作为潜在固态锂离子导体的阴离子排列。为了扩大这一新系统的能力，该项目将使用计算技术来推导出这一新建立的系统的假设稳定变化。将采用不同的实验方法来寻求实现计算确定的稳定材料，初步相纯度将通过粉末X射线衍射(PXRD)分析和同步辐射数据来测量。Rietveld精细化将被用来表征一种新材料的结构，可能结合高分辨率的单晶X射线衍射数据。元素分析将在随后通过电感耦合等离子体光学发射光谱(ICP-OES)、CHNS和核磁共振进行彻底确定。然后，研究将继续量化该材料作为固体电解质的性能，通过交流(AC)阻抗测量来评估离子传导性，通过直流(DC)极化来评估电子传导性。通过将定量数据和结构分析与从头算分子动力学(AIMD)相结合来确定Li在新材料中的传输机制，将有助于从整体上理解化学空间。

The development of solid electrolyte (SE) systems is a field that is ever-growing due to the increasing motivation to develop a commercially viable all-solid-state battery (ASSB). Currently, there are concerns with the limitations of Li-ion battery (LIB) technology, when compared with the higher hypothetical energy storage capacity of ASSBs. A focal point of ASSB development is the advancement of the state-of-the-art of solid electrolytes.Recently, a novel material was developed at the University of Liverpool, that utilised ion arrangements comparable to intermetallic systems to produce a system that has improved structural diversity and subsequently a high Li ion conductivity (Science, 2024, 383, 739-745). Such ion arrangements facilitate a wide array of cation coordination environments, providing low energy barriers and increased ionic conductivity when compared with other leading SE systems.The purpose of this research is to expand on this new structural chemistry by exploring new compositions and materials that may adopt this structure type. This involves diversification of cationic and anionic species. The hypothesis being that further increased disorder will improve the already impressive ionic conductivity of this system. Additionally, the relationship between known intermetallic structural motifs and ionic conductors will be explored further to identify other anion arrangements that are favourable as potential solid state Li ion conductors.In the pursuit to expand the capability of this novel system, the project will employ the use of computational techniques to derive hypothetically stable variations of this newly established system. Varied experimental approaches will be employed to seek to achieve computationally determined stable materials, with preliminary phase purity will be measured by Powder X-Ray Diffraction (PXRD) analysis and synchrotron data. Rietveld refinement will be used to characterise the structure of a novel material, possibly in combination with high-resolution single crystal XRD data.Elemental analysis will be thoroughly determined thereafter by inductively coupled plasma optical emission spectroscopy (ICP-OES), CHNS and NMR. Studies will then go on to quantify the performance of the material as a solid electrolyte, assessing the ionic conductivity by alternating current (AC) impedance measurements and electronic conductivity by direct current (DC) polarization. The Li-transport mechanism in newly developed materials will be understood by combining quantitative data and structural analysis with ab initio molecular dynamics (AIMD) to determine the Li transport mechanism and contribute overall to the understanding of the chemical space.