Customizable solid-state batteries toward shape-conformal and structural power supplies

With the advent of intelligent electronics and green transportation systems, power sources with customized shape, flexibility, functionality and high security are indispensable. Innovative customizable solid-state batteries have recently been explored as a key-enabling technology to achieve this vision. Such custom-made power sources enable the monolithic integration of bipolar-stacked cells onto complex-shaped substrates, maximize space utilization of devices, meanwhile minimize the use of inactive components. Hence, they hold great potential in reducing the total weight of target electronic devices, extending their lifespan, and even as structural batteries to replace structural components in robotics, implants and electric vehicles. This review describes state-of-the-art of customizable solid-state batteries with a focus on fabrication techniques and corresponding material considerations. The relationship between the battery architecture design and form-factors of cells concerning their mechanical and electrochemical properties are in focus. The challenges and future developments of customizable solid-state batteries are elaborated with respect to their potential applications. Through novel material engineering, structural evolution, on-going extension of high-throughput fabrication technology, and integration of multifunctional systems, the customizable solid-state batteries will pave their way to power a growing share of smart electronics and modern transportation systems.