TY - JOUR
T1 - Effects of cycle times and C-rate on mechanical properties of copper foil and adhesive strength of electrodes in commercial LiCoO 2 LIBs
AU - Dai, Cuiying
AU - Wang, Zhuo
AU - Liu, Ke
AU - Zhu, Xiaoxue
AU - Liao, Xiangbiao
AU - Chen, Xi
AU - Pan, Yong
N1 - Publisher Copyright:
© 2019
PY - 2019/7
Y1 - 2019/7
N2 - It is important to appraise the evolution of mechanical properties of current collectors and the adhesive strength of electrodes to reveal the chemical-mechanical coupling failure mechanism of lithium-ion batteries (LIBs), and to improve their cycling performance and cycling life. In this work, the mechanical properties of copper foil, anode, and cathode of commercial LIBs were studied under different cycling conditions by means of tensions with the aid of non-contact digital image correlation technique. It is found that different electrochemical cycle times and C-rates have great influence on the degradation of the mechanical properties of copper foil and the interfaces of graphite/copper foil and LiCoO 2 /alumina foil. The changes in elastic modulus, fracture strength and elongation of the copper foil were analyzed at 0.5C, 0.8C and 1.0C within 200 cycles, respectively. The adhesive strength of graphite/copper foil changes from its initial value 285.6 kPa to 55.5 kPa after 200 cycles at 1.0C, and the adhesive strength of LiCoO 2 /alumina foil decreases from its initial value 841.2 kPa to 132.8 kPa after 200 cycles at 1.0C.
AB - It is important to appraise the evolution of mechanical properties of current collectors and the adhesive strength of electrodes to reveal the chemical-mechanical coupling failure mechanism of lithium-ion batteries (LIBs), and to improve their cycling performance and cycling life. In this work, the mechanical properties of copper foil, anode, and cathode of commercial LIBs were studied under different cycling conditions by means of tensions with the aid of non-contact digital image correlation technique. It is found that different electrochemical cycle times and C-rates have great influence on the degradation of the mechanical properties of copper foil and the interfaces of graphite/copper foil and LiCoO 2 /alumina foil. The changes in elastic modulus, fracture strength and elongation of the copper foil were analyzed at 0.5C, 0.8C and 1.0C within 200 cycles, respectively. The adhesive strength of graphite/copper foil changes from its initial value 285.6 kPa to 55.5 kPa after 200 cycles at 1.0C, and the adhesive strength of LiCoO 2 /alumina foil decreases from its initial value 841.2 kPa to 132.8 kPa after 200 cycles at 1.0C.
KW - Adhesive strength
KW - Copper foil
KW - Digital image correlation
KW - Lithium ion battery
KW - Mechanical properties
UR - http://www.scopus.com/inward/record.url?scp=85063388349&partnerID=8YFLogxK
U2 - 10.1016/j.engfailanal.2019.03.015
DO - 10.1016/j.engfailanal.2019.03.015
M3 - Article
AN - SCOPUS:85063388349
SN - 1350-6307
VL - 101
SP - 193
EP - 205
JO - Engineering Failure Analysis
JF - Engineering Failure Analysis
ER -
