In-situ study of mechano-electrochemical coupling properties of symmetrical SnO2/Gr electrodes for lithium-ion batteries using digital image correlation

• Published in: Journal of energy storage 2023-12, Vol.74, p.109365, Article 109365
• Main Authors: Tang, Jiaping, Dai, Cuiying, Wen, Ze, Yang, Mei, Gao, Hongbin, Mao, Weiguo, Wang, Zhuo, Pan, Junan, Pan, Yong
• Format: Article
• Language: English
• Subjects: Digital image correlation; In-situ characterization; Lithium-ion battery; Mechano-electrochemical; SnO2/Gr anode
• ISSN: 2352-152X; 2352-1538
• DOI: 10.1016/j.est.2023.109365

SnO2/Gr composite as anode material for lithium-ion batteries was synthesized by an acoustic-chemical method followed by an annealing treatment. The composite exhibits high crystallinity and purity, and the weight ratio of SnO2 reaches 27.4 %. Benefit from the compound effect between material components, the SnO2/Gr anodes give notable reaction kinetics and cycling stability. The specific capacity remains 642.4 mA h g−1 after 150 cycles at 200 mA g−1. The strain field features in the symmetrical SnO2/Gr electrodes were in-situ measured during electrochemical cycles by digital image correlation technique. The distribution and variation characterizations of diffusion induced stress in the symmetrical SnO2/Gr electrodes were obtained by using mechano-electrochemical coupling constitutive equation. Furthermore, the contributions of the electrochemical and mechanical stress parts to the plane stress in the symmetrical SnO2/Gr electrodes also be discussed, respectively. The results and analytical method are critical for further revealing the failure mechanism and optimizing architecture of the SnO2/Gr electrodes for lithium-ion batteries. •SnO2/graphite composite as anode material for lithium-ion batteries was synthesized.•The features of plane strain field in symmetrical SnO2/Gr electrodes were in-situ monitored.•The evolution characteristics of diffusion induced stress in the electrodes were obtained.•The effects of electrochemical and mechanical components on lithiation induced stress were analyzed.•The mechano-electrochemical coupling mechanism for SnO2/Gr electrodes was discussed.