Tensile properties of multifunctional composites embedded with lithium-ion polymer batteries

Abstract

Multifunctional composites that combine high mechanical properties with electrical energy storage capacity are being explored for use in hybrid and electric powered vehicles. This paper evaluates the effect of embedding lithium-ion polymer (LiPo) batteries on the tensile properties and energy storage density of carbon fibre laminate and sandwich composite. The tensile modulus and failure stress of the laminate is reduced significantly by the batteries. The reduction in tensile strength is similar for one or multiple embedded batteries whereas the reduction in tensile modulus increases with the number of batteries. LiPo batteries embedded in the foam core to sandwich composite do not adversely affect the tensile properties. These findings are validated numerically with finite element (FE) modelling of the laminate and sandwich composite. The energy storage capacity and electrical properties of the LiPo battery was not changed when the composites were subjected to increasing tensile loads up to final failure.