This chapter covers common recycling methods for lithium-ion batteries (LiBs), including DES-assisted recycling of cathode active materials, binder dissolution and separation of electrode materials from spent LiBs using DESs, and the recovery and regeneration of anode graphite in DESs. The rapid and large-scale manufacturing of advanced portable electronic devices and electric vehicles (EVs) has led to a substantial increase in the production of high-capacity, rechargeable lithium-ion batteries. Improper disposal of spent LiBs can pose serious environmental and health risks, as they contain hazardous materials such as lead (Pb), cadmium (Cd), and lithium (Li). Therefore, it is crucial to develop sustainable recycling approaches to address the disposal issues of spent LiBs. The use of DESs allows for the efficient dissolution of lithium, cobalt, nickel, and other transition metals from spent cathode materials, often under milder conditions compared to traditional methods. However, further studies are needed before industrial-scale implementation to minimize the risk of lower extraction yields and to ensure the effective recovery of valuable materials.