Finite element analysis and experimental investigation on the mechanical behaviours of multifunctional sandwich structures embedded with batteries

The purpose of this study is to investigate the mechanical behaviours of sandwich structures containing embedded batteries that are the simplest approach of multifunctional energy storage composite structures. Parametric studies were performed using finite element analysis to learn how the embedded batteries affect mechanical properties of five different sandwich cores (honeycomb, semi-reentrant A, semi-reentrant B, reentrant A and reentrant B). Two types of batteries (A76 button battery and 18650 rechargeable battery) and three different loading conditions (three-point bending, compression, and shear) are adopted for this parametric study. It is found that the stiffnesses of the sandwich structures are not affected by filling the cores with batteries but there is a slight increase in the peak loads regardless of sandwich core and battery types used in this study. Experimental validation of the finite element results was conducted on some selected cases and a good agreement between them are noted. From this numerical and experimental efforts, it is concluded that embedding batteries within sandwich cores is a simple approach of realising multifunctional energy storage composite structures that offers space efficiency without degradation in mechanical properties of the structures.