Lithium-ion batteries (LIBs) find extensive use in various electronic devices, including computers, phones, and electric vehicles. Due to their widespread applications, LIBs come in diverse shapes, sizes, and compositions. These batteries contain significant amounts of critical materials such as lithium, cobalt, and nickel. Unfortunately, without proper recycling, these valuable materials are lost when electronics reach the end of their life cycle. [1]. The increasing demand for batteries, particularly in the electric vehicle (EV) industry, has led to a surge in the need for critical metals. For example, sales of electric vehicles are expected to increase to 23-40 million in 2030 compared to 5.1 million in 2018 [2]. In response to the growing demand for batteries and the subsequent need for battery materials as well as the environmental impact of discarded batterie several governments worldwide have taken significant steps to establish a complete recycling infrastructure including collection points, incentivizing recycling facilities and promoting the use of recycled materials. Legislation has been enacted in countries such as the United States, China, and the European Union to mandate the establishment of large-scale battery recycling facilities [1] [3]. These facilities play a crucial role in creating a sustainable supply chain for critical metals. This paper provides a comprehensive overview of the recycling processes for lithium-ion batteries (LIBs), covering various scales from lab experiments to industrial implementations. All these processes are built upon three distinct technologies including hydrometallurgy, pyrometallurgy and combined hydrometallurgy and pyrometallurgy processes [4] [3] [1]. Within the developed processes, only a few have successfully scaled up to industrial pilot scales. In this paper, we will explore and compare examples of both pilot-scale and industrial-scale processes. Discussing and comparing these processes will provide valuable insights for advancing sustainable battery recycling practices.