Since 1990, lithium-ion batteries (LIBs) have been booming in the last decades. Because they are ecofriendly and rechargeable, LIBs have been widely used in portable devices, electric vehicles, and even satellites and aerospace. However, the limited lifespan and intensive growth of spent LIBs result in serious accumulation and depletion to hazardous waste. This review critically summarizes the state-of-the-art of the scrapped spent LIBs on recycling benefits and national policies. Also the advantages and disadvantages of various recycling technologies on recycling efficiency, electrochemical performance of the restored materials, and economic and environmental issues are compared and discussed. A green, feasible, and sustainable recycling strategy with high efficiency for spent LIBs (including cathodes, anodes, electrolytes, and other metallic materials) is explored and discussed in detail. Finally, the recycling mode, challenges, and developing tendency of battery recycling on the battery production, battery design, and battery management system are put forward and speculated.