Impact damage tolerance of energy storage composite structures containing lithium-ion polymer batteries

Abstract

Abstract Multifunctional composite structures that combine high load-bearing properties with electrical energy storage capacity have potential application in electric and hybrid powered cars, and therefore must be impact resistant in the event of collision. This paper examines the effect of low velocity impact on the damage, compression properties and energy storage capacity of composite laminates and sandwich composites containing an embedded lithium-ion polymer (LiPo) battery. The impact responses of a carbon fibre-reinforced epoxy (CFRP) laminate and a polymer foam core sandwich composite are investigated. The materials were impacted at different incident energy levels at the location immediately above the embedded battery. The battery at the impact location increased the impact energy absorption of both the laminate and sandwich composite due to its capacity to yield and plastically deform. Impact-induced damage reduced the compressive properties of the composite laminate and sandwich composite in part due to deformation, cracking and debonding of the battery. Low impact energy events (≤4 J) had negligible effect on the residual energy storage capacity of the LiPo battery, although higher energies (≥6 J) caused an internal short circuit due to excessive plastic deformation and crushing.