Mechanical characterization and modeling for anodes and cathodes in lithium-ion batteries

JOURNAL OF POWER SOURCES

卷:392

Article

Wang, Lubing^1,2  Yin, Sha^1,2  Zhang, Chao^3,4  Huan, Yong⁵  Xu, Jun^6,7 

[1] Beihang Univ, Sch Transportat Sci & Engn, Dept Automot Engn, Beijing 100191, Peoples R China

[2] Beihang Univ, Adv Vehicle Res Ctr, Beijing 100191, Peoples R China

[3] Northwestern Polytech Univ, Dept Aeronaut Struct Engn, Xian 710072, Shaanxi, Peoples R China

[4] Northwestern Polytech Univ, Joint Int Res Lab Impact Dynam & Its Engn Applica, Xian 710072, Shaanxi, Peoples R China

[5] Chinese Acad Sci, Inst Mech, State Key Lab Nonlinear Mech LNM, Beijing 100190, Peoples R China

[6] Univ N Carolina, Dept Mech Engn & Engn Sci, Charlotte, NC 28223 USA

[7] Univ N Carolina, North Carolina Motorsports & Automot Res Ctr, Charlotte, NC 28223 USA

关键词: Battery electrodes;    Mechanical integrity;    Battery safety;    Strain rate effect;    SOC dependency;   

DOI  :  10.1016/j.jpowsour.2018.05.007

来源: Elsevier

【 摘 要 】

Mechanical properties of electrode materials have significant influence over electrochemical properties as well as mechanical integrity of lithium-ion battery cells. Here, anode and cathode in a commercially available 18650 NCA (Nickel Cobalt Aluminum Oxide)/graphite cell were comprehensively studied by tensile tests considering material anisotropy, SOC (state of charge), strain rate and electrolyte content. Results showed that the mechanical properties of both electrodes were highly dependent on strain rate and electrolyte content; however, anode was SOC dependent while cathode was not. Besides, coupled effects of strain rate and SOC of anodes were also discussed. SEM (scanning electron microscope) images of surfaces and cross-sections of electrodes showed the fracture morphology. In addition, mechanical behavior of Cu foil separated from anode with different SOC values were studied and compared. Finally, constitutive models of electrodes considering both strain rate and anisotropy effects were established. This study reveals the relationship between electrochemical dependent mechanical behavior of the electrodes. The established mechanical models of electrodes can be applied to the numerical computation of battery cells. Results are essential to predict the mechanical responses as well as the deformation of battery cell under various loading conditions, facilitating safer battery design and manufacturing.

【 授权许可】

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