The recycling of used lithium-ion batteries (LIB) is of great importance for both critical metal supplies and environmental protection. Although physical chemistry still focuses on pyrometallurgy, hydrometallurgy and electrometallurgy, modern recycling technologies are trending towards more material and energy efficiency in the sense of green chemistry. For example, through selective recycling of target metals and direct regeneration of battery materials, attempts are being made to develop short procedures to prevent the generation of secondary pollution and to improve atomic economy throughout the recycling process. In this overview, a number of technologies for recycling used LIBs are presented, especially at different recycling stages to gradually reclaim battery materials. It is clear that the extraction of critical metals and subsequent regeneration of materials are only part of the recycling process, while pretreatment to recover black mass powder from battery cells and controlling pollution are also extremely important in terms of the recycling process to minimize the impact on the environment. In addition, the green battery design, as well as the process design, are at the top of the list of research that requires profound and elaborate efforts with regard to the entire life cycle of LIB. It is expected that this review could provide guidance on how to implement the principles of green chemistry in recycling used LIBs and stimulate further discussion on improving the green grade of the process.