Register for free to
view the full innovation profile.
This technology allows for electric power storage to be integrated in a strong, lightweight carbon fiber material with increased charge storage and mechanical strength.
About
Combining structural integrity with energy storage in one material results in the creation of advanced multi-functional materials suitable for aerospace, aviation, automotive, building construction, portable electronics, home appliances, and many other applications. A cross-disciplinary team of scientists and engineers at Northern Arizona University have developed a lightweight polymer electrolyte which may be used, together with carbon fiber cloths, to develop materials that are moldable, rigid after curing, and capable of storing and releasing electrical energy like a supercapacitor. The supercapacitor function of the material is achieved by laying up the material in a layup similar to that of an electric double layer capacitor (EDLC), i.e. supercapacitor. The EDLC stores electrical charges in two electrical layers developed at the electrode-electrolyte interface; to prevent short-circuiting of the EDLC, the electrodes are separated by a separator (Figure 1). The separator allows ionic flow and restricts electron flow between electrodes. The charge storage capacity of EDLCs is achieved by increasing the surface area of the electrodes; the latter is achieved through a process called functionalization, which facilitates the application of various types of high surface area carbon coatings on the electrodes/carbon clothes. The charges stored on the electrodes are supplied by the electrolyte, which in most electronic applications is a liquid, whereas in our material is a solid (to facilitate its structural strength). Laying up the material in multiple layers leads to both increased charge storage and increased mechanical strength of the material. The formulation of the solid polymer electrolyte, the functionalization of the carbon fiber cloth electrodes, and the material fabrication process, all play important roles in the successful development of the structural supercapacitor. Current characteristics of the material include specific capacitance of 51.90 F/kg and energy density of 4.61 mWh/kg, both achieved with the electrolyte that has an ionic conductivity of 9.52x10-4 S/cm and compressive strength of 2.55 MPa. This material may be fabricated in two- and three-dimensional shapes to accommodate a variety of form factor requirements for achieving optimal design of aerospace or automotive applications. This material is ready for integration into prototype applications.
Key Benefits
This technology allows for power storage to be integrated in a strong and lightweight carbon fiber based material with the benefit of reducing weight and volume of systems that can be fabricated with the material, which otherwise would use stand-alone components to provide the power storage functionality. Specific advantages of the technology include: • Added power storage capability to an otherwise simply structural material • Potential for no compromise in strength and durability of the structural material • Reduced or non-existent electrical energy storage aside from the body of the system • Material fabrication process allows for virtually any desired shape to be achieved • Multi-functional material that provides opportunities for leaner mechanical systems
Applications
This material may be deployed in a wide range of applications specific to aerospace, automotive (e.g. hybrid vehicles), portable electronics (e.g. a cell phone case that is also the power storage unit), portable power systems, energy conversion technologies (e.g. backing of solar panels that store the converted electricity by the panel when the grid is saturated). Localized material damage, such as punctures or cuts, will not compromise the functionality of the entire material – the undamaged areas will retain their functionality. Immediate deployment of the material can be pursued in solar panels used in terrestrial solar panel farms or in satellite solar panels. Deployment of this material in aerospace structures can substantially reduce the payload of the launched vehicles, creating room for added instrumentation or supplies.