Arya, AnilGaur, AnuragSharma, A.L.2024-01-212024-08-132024-01-212024-08-132021-09-069781000470512978036769425810.1201/9781003141761-7https://kr.cup.edu.in/handle/32116/3669This chapter provides an overview of challenges faced by different devices and their remedies. Supercapacitors are energy storage devices and have gained the attention of the scientific community due to their high power density, long cycle life, and a broad range of applications. The existing carbon/metal oxide-based electrode symmetric cell has a lower energy density. Energy density is an important parameter that needs to be improved with the existing high power density. The only feasible strategy is the development of hybrid architecture. The cell performance is strongly influenced by the contact between different components of the cell. The contact between the current collector as well as the active material needs to be improved for minimizing the interfacial resistance and for improving the charge transferability of the electrode material. The energy production through hydroelectric cells, based on metal oxides and their composites, by the splitting of water has turned out to be a feasible alternative to other green energy sources. � 2022 Taylor & Francis Group, LLC.en-USBook chapterhttps://www.taylorfrancis.com/books/9781003141761/chapters/10.1201/9781003141761-7