Engineering materials that can store electrical energy in structural load paths can revolutionize lightweight design across transport modes. Stiff and strong batteries that use solid‐state electrolytes and resilient electrodes and separators are generally lacking. Herein, a structural battery composite with unprecedented multifunctional performance is demonstrated, featuring an energy density of 24 Wh kg−1 and an elastic modulus of 25 GPa and tensile strength exceeding 300 MPa. The structural battery is made from multifunctional constituents, where reinforcing carbon fibers (CFs) act as electrode and current collector. A structural electrolyte is used for load transfer and ion transport and a glass fiber fabric separates the CF electrode from an aluminum foil‐supported lithium–iron–phosphate positive electrode. Equipped with these materials, lighter electrical cars, aircraft, and consumer goods can be pursued.

Structural batteries (SBs) are a growing research subject worldwide. The idea is to provide massless energy by using a multifunctional material. This technology can provide a new pathway in electrification and offer different design opportunities and significant weight savings in vehicle applications. The type of SB discussed here is a multifunctional material that can carry mechanical loads and simultaneously provide an energy storage function. It is a composite material that utilizes carbon fibers (CFs) as electrodes and structural reinforcement which are embedded in a multifunctional polymer matrix (i.e., structural battery electrolyte). A feasible composite manufacturing method still needs to be developed to realize a full-cell SB. UV initiated polymerization induced phase separation (PIPS) has previously been used to make bicontinuous structural battery electrolytes (SBE) with good ionic conductivity and mechanical performance. However, UV-curing cannot be used for fabrication of a full-cell SB since a full-cell is made of multiple layers of nontransparent CFs. The present paper investigates thermally initiated PIPS to prepare a bicontinuous SBE and an SB half-cell. In addition, the effect of curing temperature was examined with respect to curing performance, morphology, ionic conductivity, and mechanical and electrochemical performance. The study revealed that thermally initiated PIPS provides a robust and scalable process route to fabricate SBs. The results of this study are an important milestone in the development of SB technology as they allow for the SB fabrication for an actual application. However, other challenges still remain to be solved before this technology can be introduced into an application.

Electric Vehicles In article number http://doi.wiley.com/10.1002/aesr.202000093 by Leif E. Asp and co‐workers, renewable electrical energy stored in the body‐in‐white and interior panels of future electric cars. Structural batteries made from carbon fiber‐reinforced composites reduce vehicle weight to increase efficiency and driving range.