## 1 Introduction  
The mass production of chemical lithium-ion energy sources (Li-ion batteries, LIBs) used in electric vehicles has resulted in a large stream of waste from used batteries and accumulators of various types appearing on the market. Therefore, recycling companies have often not been prepared to manage some of those new waste streams efficiently [1, 2]. In addition, the latest dynamic geopolitical situation forced the industry to take very quick and radical actions to secure secondary sources of strategic metals, e.g., copper, nickel,cobalt and lithium. It resulted in high prices and a surge in interest of the metallurgical industry in the development of new processes for the recovery of secondary raw materials, often in direct cooperation with the scientific world [3; 4; 5]. The number of publications and technological studies presenting descriptions of processes or scientific research related directly or indirectly to the recycling of the stream of used and/or waste lithium-ion cells is very large. As described by [PERSON] and [PERSON] [6], it can be assumed that the number of publications in this area is growing exponentially. It can be noted that the articles scheduled for publication in the first half of 2023 cover very narrow problems to be solved, focusing mostly on the individual physicochemical operations which are a part of the processing and/or recycling of polymetallic chemical waste of lithium-ion energy sources (LIBs). Those publications concentrate on:  
* the management of a very complex electrolyte in terms of chemical composition [7; 8];
* the use of waste separators from used cells as ecological reducers of cathode metals for the roasting process [9];
* the recovery of by-products of LIB hydrometallurgical processes, including graphite (C/graphite), sodium sulphate (Na\({}_{2}\)SO\({}_{4}\)) and lithium carbonate (Li\({}_{2}\)CO\({}_{3}\)) [10];
* the selective recovery of lithium by an acid-free mechanical-chemical method [11];
* the selective leaching of nickel, cobalt, manganese, lithium and iron [12];
* or the innovative co-fusion of used Li-ion materials with copper slag [13]. Table 1 presents a list of patent applications and patents in the field related to the treatment and/or recycling of the stream of used and/or waste lithium-ion cells by pyrometallurgical, hydrometallurgical and electrometallurgical methods. The review was carried out using the desk research technique (existing sources method; secondary sources method) consisting of already existing available data from various sources, e.g., Polish Patent Office [14], European Patent Office [15], World Intellectual Property Organization [16], Google Patents [17] and Justia Patents [18]. The main conclusion that comes to mind after analyzing all the referenced documents is that the stream of waste Li-ion cells, due to the very complex chemical composition, cannot be processed with one classic pyrometallurgical or hydrometallurgical path. The desired effect of raw material recovery can only occur as a result of combining different unit processes which are used in different fields of metallurgy [2; 19; 20]. The hydrometallurgical stage of battery mass processing, which may or may not be preceded by thermal treatment of the substrate, usually consists of acidic or alkaline leaching of properly prepared waste (after disassembly and mechanical treatment processes). These processes should be characterized by technological and economic efficiency and the lowest impact on the environment through the use of the smallest amounts of water, chemical substances and materials, as well as energy. After the first stage of hydrometallurgical treatment, the obtained semi-finished products are processed in a series of physical and chemical operations, which lead to the separation and concentration of valuable or burdensome components between the appropriate phases, in the form of commercial products, semi-finished products for separate technological processes (pyrometallurgical and/or hydrometallurgical) or waste [21].