Porosity in electrochemical energy storage materials for superior performance gaining: insight into property...

The use of renewable energy, electric vehicles, and high-density compact devices requires the power density, long-term stability, and long cycle life of the electrochemical energy storage (ESS) systems. Ion transport, charge storage and mechanical stability of the electrode can be improved with high specific surface area and porous electrodes with well-designed pore structures and high accessibility of electrolytes to the electrodes. The present work critically outlines the current trends in the porous electrode materials, which are porous carbons, inorganic porous structures and coordinated hybrid/composite structures. The relationships between structure, property, and performance that dictate electrochemical behavior and design approaches such as hierarchical porosity, surface functionalization and heterostructure hybridization are pointed out as having a contribution to improving capacitance, energy density and cycling stability. The primary challenges in the manner, in which such materials evolved in the laboratory can be transferred to the practice in the real world, including scaling up to mass production, the volumetric energy density, and the stability of electrodes on the actual cycling, are also stated. Efforts in the recent past have suggested that the objective of pore engineering should be oriented towards equilibrium between the surface area, mechanical stability, and volumetric functionality. The devices of the future EES will need a blend of rational material design and manufacturability approaches to help close the gap between new and innovative porous electrode concepts and commercial energy storage technologies.