The environmental pollution caused by the valuable chemical components such as cobalt, copper, lithium, mixture of organic electrolyte and salts of either low quality or spent lithium-ion batteries (LiBs) deposited into the environments necessitates responsive recovery technologies. Since Sony made the first commercial lithium-ion cell in 1991, it has been accorded more attention being superior to other types of batteries in terms of energy density, which is a critical parameter for portable electronics as well as hybrid and electric vehicles. Lithium ion batteries are the systems preferred as electrochemical power sources in portable batteries segment such as mobile telephones, personal computers, video-cameras and other modern-life appliances as well as in vehicles with electric drive due to its favorable characteristics (Contestabile et al., 2001; Gaines, 2011; Nan et al., 2005; Wang et al., 2011). As LiBs progressively dominate, the amounts of valuable chemical components that will be deposited will be proportional to the number of LiBs used after their life-span has expired. Therefore, recycling that constitutes the most generally acceptable environmentally friendly method of managing these wastes must be taken serious, to minimize environmental toxicity, for economic gains and reduction in dependence on foreign resources or on virgin materials for productions in the industry as well as for sustainability of the natural resources (Contestabile et al., 1999; Dewulf, et al., 2010; Graham-Rowe, 2010; Hitachi, 2011; Kumar, 2011; Wang et al., 2011). The methods could be on the laboratory scale, industrial or commercial scale level. These as-recovered metals or their respective compounds (cobalt, lithium, manganese, and nickel) are not only valuable metals but are alternative precursors for new batteries formulations. Thus, several attempts have been made to review the old processes considered green and non-green chemistries to either improve on the existing ones or propose new recovery processes that are considered simple and of industrial-scale (Kondás et al, 2006; Nan et al., 2005). However, the cells used in cell phones and laptops are not fully recycled and consequently causing unsustainable open loop in the industrial cycle (Wang et al., 2011).
Although according to the U.S. government, spent LiBs have been classified as non-environmentally hazardous wastes or rather call “green batteries” and thus safe for disposal in the normal municipal waste stream unlike other battery chemistries that contain Cd, Pb or Hg, the presence of flammable and toxic elements or compounds may make their safe disposal to become a serious problem. For instance, the mixture of dimethyl carbonate (DMC) and ethylene carbonate (EC) used as solvent is flammable, while the polyvinylidene fluoride (PVDF) used as binder irrespective of its percentage in the battery formulation is toxic when burns consequent to the release of gaseous HF. Besides, the NMP commonly used as a solvent for the electrode active materials (cathode and anode) fabrication during slurry preparation has been reported as toxic and therefore environmentally incompatible (Alfonso et al., 2004; Castillo et al., 2002; Mitchell, 2006; Robert, 2000; Roth and Orendorff, 2012; Wang et al., 2011). As there is a general saying and belief that “health is wealth”, similarly, “healthy environment is a wealthy environment”. On the other hand, “polluted environment is an unhealthy and un-wealthy environment”. Therefore, recycling is of great importance to save our immediate environment and for waste management sustainability.