Weihao Zeng, Fanjie Xia, Juan Wang, Jinlong Yang, Haoyang Peng, Wei Shu, Quan Li, Hong Wang, Guan Wang, Shichun Mu, Jinsong Wu
{"title":"Entropy-increased LiMn<sub>2</sub>O<sub>4</sub>-based positive electrodes for fast-charging lithium metal batteries.","authors":"Weihao Zeng, Fanjie Xia, Juan Wang, Jinlong Yang, Haoyang Peng, Wei Shu, Quan Li, Hong Wang, Guan Wang, Shichun Mu, Jinsong Wu","doi":"10.1038/s41467-024-51168-1","DOIUrl":null,"url":null,"abstract":"<p><p>Fast-charging, non-aqueous lithium-based batteries are desired for practical applications. In this regard, LiMn<sub>2</sub>O<sub>4</sub> is considered an appealing positive electrode active material because of its favourable ionic diffusivity due to the presence of three-dimensional Li-ion diffusion channels. However, LiMn<sub>2</sub>O<sub>4</sub> exhibits inadequate rate capabilities and rapid structural degradation at high currents. To circumvent these issues, here we introduce quintuple low-valence cations to increase the entropy of LiMn<sub>2</sub>O<sub>4</sub>. As a result, the entropy-increased LiMn<sub>2</sub>O<sub>4</sub>-based material, i.e., LiMn<sub>1.9</sub>Cu<sub>0.02</sub>Mg<sub>0.02</sub>Fe<sub>0.02</sub>Zn<sub>0.02</sub>Ni<sub>0.02</sub>O<sub>4</sub>, when tested in non-aqueous lithium metal coin cell configuration, enable 1000 cell cycles at 1.48 A g<sup>-1</sup> (corresponding to a cell charging time of 4 minutes) and 25°C with a discharge capacity retention of about 80%. We demonstrate that the increased entropy in LiMn<sub>2</sub>O<sub>4</sub> leads to an increase in the disordering of dopant cations and a contracted local structure, where the enlarged LiO<sub>4</sub> space and enhanced Mn-O covalency improve the Li-ion transport and stabilize the diffusion channels. We also prove that stress caused by cycling at a high cell state of charge is relieved through elastic deformation via a solid-solution transition, thus avoiding structural degradation upon prolonged cycling.</p>","PeriodicalId":19066,"journal":{"name":"Nature Communications","volume":null,"pages":null},"PeriodicalIF":14.7000,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11349939/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Nature Communications","FirstCategoryId":"103","ListUrlMain":"https://doi.org/10.1038/s41467-024-51168-1","RegionNum":1,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MULTIDISCIPLINARY SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
Fast-charging, non-aqueous lithium-based batteries are desired for practical applications. In this regard, LiMn2O4 is considered an appealing positive electrode active material because of its favourable ionic diffusivity due to the presence of three-dimensional Li-ion diffusion channels. However, LiMn2O4 exhibits inadequate rate capabilities and rapid structural degradation at high currents. To circumvent these issues, here we introduce quintuple low-valence cations to increase the entropy of LiMn2O4. As a result, the entropy-increased LiMn2O4-based material, i.e., LiMn1.9Cu0.02Mg0.02Fe0.02Zn0.02Ni0.02O4, when tested in non-aqueous lithium metal coin cell configuration, enable 1000 cell cycles at 1.48 A g-1 (corresponding to a cell charging time of 4 minutes) and 25°C with a discharge capacity retention of about 80%. We demonstrate that the increased entropy in LiMn2O4 leads to an increase in the disordering of dopant cations and a contracted local structure, where the enlarged LiO4 space and enhanced Mn-O covalency improve the Li-ion transport and stabilize the diffusion channels. We also prove that stress caused by cycling at a high cell state of charge is relieved through elastic deformation via a solid-solution transition, thus avoiding structural degradation upon prolonged cycling.
期刊介绍:
Nature Communications, an open-access journal, publishes high-quality research spanning all areas of the natural sciences. Papers featured in the journal showcase significant advances relevant to specialists in each respective field. With a 2-year impact factor of 16.6 (2022) and a median time of 8 days from submission to the first editorial decision, Nature Communications is committed to rapid dissemination of research findings. As a multidisciplinary journal, it welcomes contributions from biological, health, physical, chemical, Earth, social, mathematical, applied, and engineering sciences, aiming to highlight important breakthroughs within each domain.