Electrodes having nanostructure and/or utilizing nanoparticles of active materials can exhibit improved performance in energy storage devices compared to traditional electrodes that do not take advantage of nanomaterials. However, one of the challenges is forming a sufficiently large area of uniform active-material nanoparticles with desirable thickness or active mass loading. Only thin electrodes and low active mass loadings have been demonstrated in electrodes having nanoparticles due to the development of cracks and pinholes in electrodes having commercially relevant thicknesses or active mass loadings. Therefore, a need exists for thick electrodes having nanoparticles of active materials and methods for making the same.

PNNL researchers have developed electrodes having nanostructure and/or utilizing nanoparticles of active materials and having high mass loadings of the active materials that can be made to be physically robust and free of cracks and pinholes. The electrodes include nanoparticles having electroactive material, which nanoparticles are aggregated with carbon into larger secondary particles. The secondary particles can be bound with a binder to form the electrode. For example, a slurry containing the secondary particles can be formed and then casted into electrodes with high, commercially relevant mass loadings. The same has traditionally not been true of slurries made from nanoparticles themselves. The fabrication methods are capable of yielding the secondary particles, such that thick electrodes can be made to uniformly cover large areas without defects such as cracks and pinholes.