Investigation of the mechanical behaviour of lithium-ion batteries by an indentation technique

Abstract Indentation is an alternative technique for the measurement of a material׳s elastoplastic properties. It can be used when the classical tensile test approach is not feasible (thin film, very small components, etc.). This paper presents the results of experiments in which this technique has been exploited to investigate the mechanical properties of the multi-layered structure of lithium-ion batteries with the aim of gaining a better understanding of their mechanical integrity. Indentation tests were performed separately on different layers of a lithium-ion battery using a Berkovich indenter. In order to perform the tests, fused silica substrate (which has well-known mechanical properties) was used to constrain the samples. The elasticity of the anode and the current collectors were obtained from the unloading curve of the measured indentation load–displacement data. Also, the individual stress–strain curves were calculated through reverse engineering of the loading curve. A commercial finite element software (ABAQUS) was used to perform numerical simulations comprising axisymmetric elements representing the Al and Cu foil current collectors. Micro-tensile tests were also carried out on these foils. Agreement was obtained between the outcomes of the micro-tensile and the results of the reverse engineering of the indentation tests. A micro-structure analysis was also performed to give an insight into the structure of the battery components which is necessary for small scale mechanical characterization.

[1]  J. V. Stebut,et al.  Influence of indentation depth on the determination of the apparent Young's modulus of bi-layer material: Experiments and numerical simulation , 2005 .

[2]  Huajian Gao,et al.  Elastic contact versus indentation modeling of multi-layered materials , 1992 .

[3]  Baoxing Xu,et al.  Determining engineering stress-strain curve directly from the load-depth curve of spherical indentation test , 2010 .

[4]  Johann Michler,et al.  Determination of plastic properties of metals by instrumented indentation using different sharp indenters , 2003 .

[5]  Zhihui Xu,et al.  Finite element analysis of substrate effects on indentation behaviour of thin films , 2004 .

[6]  William D. Nix,et al.  Effects of the substrate on the determination of thin film mechanical properties by nanoindentation , 2002 .

[7]  G. Pharr,et al.  An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments , 1992 .

[8]  Marco Giglio,et al.  A study of a micro-indentation technique for estimating the fracture toughness of Al6061-T6 , 2014 .

[9]  Nagahisa Ogasawara,et al.  A simple framework of spherical indentation for measuring elastoplastic properties , 2009 .

[10]  Noel P. O’Dowd,et al.  Use of scaling functions to determine mechanical properties of thin coatings from microindentation tests , 2001 .

[11]  R. Bradt,et al.  On the Vickers Indentation Fracture Toughness Test , 2007 .

[12]  George M. Pharr,et al.  On the measurement of stress–strain curves by spherical indentation , 2001 .

[13]  Yichun Zhou,et al.  Measuring elastic–plastic properties of thin films on elastic–plastic substrates by sharp indentation , 2009 .

[14]  T. Wierzbicki,et al.  Calibration and finite element simulation of pouch lithium-ion batteries for mechanical integrity , 2012 .

[15]  T. Wierzbicki,et al.  Modeling and short circuit detection of 18650 Li-ion cells under mechanical abuse conditions , 2012 .

[16]  J. Vlassak,et al.  Measuring elastoplastic properties of thin films on an elastic substrate using sharp indentation , 2007 .

[17]  Jian Lu,et al.  A new method to extract the plastic properties of metal materials from an instrumented spherical indentation loading curve , 2004 .

[18]  R. King,et al.  Elastic analysis of some punch problems for a layered medium , 1987 .

[19]  John C. Lambropoulos,et al.  Nanoindentation technique for measuring residual stress field around a laser-induced crack in fused silica , 1998 .

[20]  Sandrine Bec,et al.  Improvements in the indentation method with a surface force apparatus , 1996 .

[21]  S. Timoshenko,et al.  Theory Of Elasticity. 2nd Ed. , 1951 .

[22]  Jianguo Lin,et al.  A study on the determination of plastic properties of metals by instrumented indentation using two sharp indenters , 2007 .