Multifunctional structural lithium-ion battery for electric vehicles

Abstract

An innovative concept for a multifunctional structural battery using lithium-ion battery materials as load bearing elements in a sandwich panel construction has been demonstrated. The structural battery prototype has exhibited an initial capacity of 17.85 Ah, an energy density of 248 Wh L⁻¹, a specific energy of 102 Wh kg⁻¹, and a capacity retention of 85.8% after 190 charge–discharge cycles at ~C/3 rate and eight mechanical loading cycles (upto 1060 N). The mechanical stiffness in three-point bend tests follows expectations based on sandwich beam theory, proving that the battery materials are sharing in the load-carrying function of the sandwich panel. While areas for improvement of the fabrication and performance of the prototype still exist, the results of the current investigation demonstrate the promising potential of the proposed structural battery concept for the efficient use of space and mass in an electric vehicle.