物理化学学报 >> 2023, Vol. 39 >> Issue (8): 2211017.doi: 10.3866/PKU.WHXB202211017

所属专题: 固态电池

综述 上一篇    下一篇

固态锂电池界面优化策略的研究进展

赵永智, 陈晨阳, 刘文燚, 胡伟飞, 刘金平()   

  • 收稿日期:2022-11-08 录用日期:2022-12-12 发布日期:2022-12-19
  • 通讯作者: 刘金平 E-mail:liujp@whut.edu.cn
  • 基金资助:
    国家自然科学基金(51972257);国家自然科学基金(52172229);中央高校基本科研业务费专项资金(2022IVA197)

Research Progress of Interface Optimization Strategies for Solid-State Lithium Batteries

Yongzhi Zhao, Chenyang Chen, Wenyi Liu, Weifei Hu, Jinping Liu()   

  • Received:2022-11-08 Accepted:2022-12-12 Published:2022-12-19
  • Contact: Jinping Liu E-mail:liujp@whut.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(51972257);the National Natural Science Foundation of China(52172229);the Fundamental Research Funds for the Central Universities(2022IVA197)

摘要:

固态锂电池具有安全性好、能量密度高等优点,在新能源汽车和智能电子等领域具有广泛的应用前景。然而,由化学/电化学和物理因素引起的界面副反应与高界面阻抗问题制约了其进一步发展。先前的综述已对解决化学/电化学界面问题的方法有了相对全面的阐述,但并未细致讨论不同结构固态电池中物理界面的影响及应对策略。本文将简要介绍化学/电化学界面问题及其解决方案;重点按结构特点将固态锂电池分为三明治结构、粉末复合结构和3D一体化结构,细致地分析不同电池结构的物理界面特点与优化策略,并对各种策略的优缺点进行比较分析;最后,对固态锂电池电极/电解质界面的未来研究方向进行展望。

关键词: 固态锂电池, 界面阻抗, 化学/电化学界面, 物理界面, 优化策略

Abstract:

With the rapid development of electric vehicles and intelligent electronics, Li-based batteries are required to have a higher specific capacity and better safety. To develop batteries with higher energy densities, Li may be used as an anode material owing to its higher theoretical capacity (3860 mAh·g−1, 10 times higher than graphite) and low redox potential (−3.04 V vs. the standard hydrogen electrode). However, uncontrolled Li dendrite growth may occur during electrochemical Li plating/stripping in the liquid electrolyte and may penetrate the separator, resulting in a short circuit of the battery. In addition, the conventional liquid organic electrolyte is flammable and easy to leak, posing safety concerns regarding fire and explosion risks. To address these issues, solid-state electrolytes are considered as a particularly ideal alternative because of their desirable mechanical properties, highly reduced flammability, and reduced risk of leakage. Such properties are expected to prevent Li dendrite growth, mitigate structural damage of the Li anode, and improve battery safety. Nonetheless, it is still a great challenge to manufacture solid-state batteries with high areal capacity and good rate performance stems from the high interfacial resistance between the electrolyte and electrode, which hinders Li-ion transport. Therefore, understanding and addressing the general interface issues in solid-state batteries is key to manufacturing high-performance solid-state lithium batteries. Interface issues in solid-state batteries are highly complex and may be broadly categorized into chemical/electrochemical interface and physical interface problems. The chemical/electrochemical interface problem comprises the narrow electrochemical stability window, elemental interdiffusion, and space charge layers, while the physical interface problem can be divided into rigid interfacial contact, volume change during cycling, and fracture and pulverization caused by stress accumulation. Previous reports represent a relatively comprehensive summary of the methods to solve the chemical/electrochemical interface problems but do not discuss in detail the influence of physical interfaces in solid-state batteries of different structures and the related addressing strategies. First, this review will briefly introduce the chemical/electrochemical interface problems and their solutions. Then, solid-state lithium batteries are divided into divided into the sandwich structure, powder composite structure, and 3D integrated structure, according to the key structural characteristics; the physical interface characteristics and optimization strategies of different battery structures are further analyzed in detail, and the advantages and disadvantages of each system are compared and analyzed. Finally, the future research direction of the electrode/electrolyte interface in solid-state lithium batteries is presented.

Key words: Solid-state lithium battery, Interfacial impedance, Chemical/Electrochemical interface, Physical interface, Optimization strategy