Structural batteries are hybrid and multifunctional composite materials able to carry load and store electrical energy in the same way as a lithium ion battery. In such a device, carbon fibres are used as the primary load carrying material, due to their excellent strength and stiffness properties, but also as the active negative electrode providing the energy storage functionality. Structural batteries can be made using a traditional laminated battery architecture similar to that of a fibre reinforced polymer composite laminate in which the positive electrode is also reinforced with carbon fibres coated with lithium iron phosphate.

Structural battery aircraft structure
Figure 2. Structural battery aircraft structure.

The research comprises pursuing several research tracks involving studying electrode materials (one being carbon fibres), matrix materials which provide stiffness for the composite while still being ionically conductive (structural battery electrolytes), device development, assembly, scale-up, demonstration, multiphysics modelling, design and applications. Possible ground-breaking applications for such innovative material concepts are casings for mobile phones, laptops or structural components of cars and airplanes that simultaneously carry load and store electrical energy, enabling substantial weight savings.

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