物理化学学报 >> 2021, Vol. 37 >> Issue (12): 2104003.doi: 10.3866/PKU.WHXB202104003

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原位修饰策略实现高倍率室温固态锂电池

赵江辉1,2, 谢茂玲3, 张海洋2, 易若玮2, 胡晨吉2,4, 康拓2, 郑磊1,2, 崔瑞广2, 陈宏伟3, 沈炎宾1,2,*(), 陈立桅2,4   

  1. 1 中国科学技术大学纳米技术与纳米仿生学院,合肥 230026
    2 中国科学院苏州纳米技术与纳米仿生研究所,国际实验室卓越纳米科学中心,江苏 苏州 215123
    3 华侨大学材料科学与工程学院,福建 厦门 361021
    4 上海交通大学化学化工学院,上海 200240
  • 收稿日期:2021-04-01 录用日期:2021-04-23 发布日期:2021-04-28
  • 通讯作者: 沈炎宾 E-mail:ybshen2017@sinano.ac.cn
  • 作者简介:第一联系人:

    These authors contributed equally to this work.

  • 基金资助:
    国家自然科学基金(21625304);国家自然科学基金(21733012);国家自然科学基金(21772190);中国科学技术部国家重点研发计划(2016YFB0100102)

In Situ Modification Strategy for Development of Room-Temperature Solid-State Lithium Batteries with High Rate Capability

Jianghui Zhao1,2, Maoling Xie3, Haiyang Zhang2, Ruowei Yi2, Chenji Hu2,4, Tuo Kang2, Lei Zheng1,2, Ruiguang Cui2, Hongwei Chen3, Yanbin Shen1,2,*(), Liwei Chen2,4   

  1. 1 School of Nano-Tech and Nano-Bionics, University of Science and Technology of China, Hefei 230026, China
    2 i-Lab, CAS Center for Excellence in Nanoscience, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, Jiangsu Province, China
    3 College of Materials Science and Engineering, Huaqiao University, Xiamen 361021, Fujian Province, China
    4 School of Chemistry and Chemical Engineering, Shanghai Jiaotong University, Shanghai 200240, China
  • Received:2021-04-01 Accepted:2021-04-23 Published:2021-04-28
  • Contact: Yanbin Shen E-mail:ybshen2017@sinano.ac.cn
  • About author:Yanbin Shen, Email: ybshen2017@sinano.ac.cn; Tel.: +86-512-62872503
  • Supported by:
    the National Natural Science Foundation of China(21625304);the National Natural Science Foundation of China(21733012);the National Natural Science Foundation of China(21772190);the Ministry of Science and Technology of China(2016YFB0100102)

摘要:

固态锂电池由于其安全特性与良好的电化学性能而备受关注。但电极内锂离子传导通道不顺畅及电极-电解质界面接触阻抗大以及界面发生副反应等问题仍然阻碍着固态电池的实际应用。本工作在电极内部及电极与Li1.5Al0.5Ge1.5(PO4)3 (LAGP)电解质之间原位聚合碳酸亚乙烯酯固态聚合物电解质(PVC-SPE),构建了正极内部的离子传导网络,改善了电解质-电极界面的接触,而且还有效阻止了锂负极与LAGP电解质之间的副反应。Li | LAGP | LiFePO4固态电池具有良好的循环性能和倍率充放电性能,0.2C循环200次仍有98%的容量保持率,3C倍率放电容量是0.2C容量的72.4%。这种原位聚合制备高性能固态电池有希望成为解决界面问题与构建电极内离子传导网络的方法。

关键词: 离子网络, 界面, 原位聚合, 固态电池

Abstract:

The increasing development of society has resulted in the ever-growing demand for energy storage devices. To satisfy this demand, both energy density and safety performance of lithium batteries must be improved, which is challenging. Solid-state lithium batteries are promising in this regard because of their safe operation and high electrochemical performance. In recent years, intense effort has been devoted toward the exploration of materials with high ionic conductivity for room-temperature solid-state batteries. Among several types of solid-state electrolytes, Li1.5Al0.5Ge1.5(PO4)3 (LAGP), an inorganic NASICON-type electrolyte, has drawn considerable attention because of its high ionic conductivity, wide electrochemical window, and environmental stability. However, the formation of lithium-ion-conducting networks within the electrode and between the electrode-LAGP interface is limited because of high interfacial resistance caused by the direct contact and volume expansion between the electrode and electrolyte. Thus, the application of LAGP in the fabrication of solid-state batteries is limited. Moreover, the occurrence of the unavoidable side reaction because of the direct contact of LAGP with the lithium metal anode shortens battery life. In addition, the rigid brittle nature of the LAGP electrolyte leads to the limits the facile fabrication of solid-state batteries. To overcome these limitations, herein, a novel strategy based on in situ polymerization of a vinylene carbonate solid polymer electrolyte (PVC-SPE) was proposed. The in situ formed PVC-SPE can effectively construct ion-conducting pathways within the cathode and on the interfaces of the LAGP electrolyte and electrodes. Furthermore, the PVC-SPE can significantly inhibit the side reaction between the lithium anode and LAGP electrolyte. The electrochemical performances of Li | LAGP | Li and Li | LAGP | Li with in situ PVC-SPE modified interface symmetrical solid-state batteries were compared. The in situ modified Li | LAGP | Li symmetrical solid-state battery exhibited stability toward plating and stripping for over 2700 h and a low overpotential (34 mV) at room temperature. Moreover, a Li | LAGP | LiFePO4 solid-state battery exhibited a capacity retention of 94% at 0.2 C after 200 cycles with a capacity of 158 mAh·g-1. In addition, high rate capability (72.4% capacity retention at 3 C) was achieved at room temperature. Therefore, the proposed in situ modification strategy was found to resolve the interface-related problem and facilitated the construction of the ion-conducting network within the electrode; thus, it can be a promising approach for the fabrication of high-performance solid batteries.

Key words: Ion network, Interface, In situ polymerization, Solid-state battery

MSC2000: 

  • O646