In-operando deformation studies on the mechano-electrochemical mechanism in free-standing MWCNTs/V2O5 lithium ion battery electrode.

Abstract Free-standing MWCNTs/V 2 O 5 nanobelts composite architecture electrodes for lithium ion batteries (LIBs) are prepared based on hydrothermal method, electrostatic self-assembly approach and vacuum filtration deposition technique. Such kind of nanoarchitecture enhances the electrochemical kinetics and structural stability of V 2 O 5 cathodes. The distribution and evolution features of plane strains in free-standing MWCNTs/V 2 O 5 cathodes surface are in-operando monitored by using digital image correlation method and systematically discussed. The strain results show that the evolution of strain against potential obeys general Arrhenius relation under galvanostatic charge-discharge cycling. Considering the effect of lithium ion concentration, the elastic modulus of 20 wt% MWCNTs/V 2 O 5 electrode is confirmed via nanoindentation. The evolutions of average plane stresses in the free-standing MWCNTs/V 2 O 5 electrodes, as well as the contributions of mechanical and electrochemical components, are evaluated and discussed by mechano-electrochemical constitutive equation during electrochemical process. The analytical methods used in this article are universal for revealing the electrode mechano-electrochemical failure mechanism in LIBs. Highlights • MWCNTs/V 2 O 5 nanobelt nanocomposites were prepared by electrostatic self-assembly. • The evolution of plane strain in MWCNTs/V 2 O 5 cathodes is in-operando monitored. • The relationship of voltage and strain was established by general Arrhenius formula. • The stresses in MWCNTs/V 2 O 5 cathode varied with charging-discharging cycles. • The results are useful for revealing mechano-electrochemical mechanisms of LIBs. [ABSTRACT FROM AUTHOR]