An analysis of the chemical composition of spent lithium ion (Li-ion) batteries for personal computers (PCs) was conducted, and an investigation of the separation of each metal (Li, Co, Ni, Cu) from the Li-ion batteries was carried out by burning under a vacuum, crushing and screening, in order to recover rare metals. A Li-ion battery is structured by multilayered electrodes of four-layered foils composed of an anode, a cathode and two separators rolled cylindrically around a core steel bar. Seven kinds of metals, including Li, Co, Ni, Fe, Mn, Al and Cu, are the primary metals in the battery. The total mass of the Li-ion battery used in this study was 39.7 g. The mass of Li and Co was 1.38 g and 10.3 g, respectively. The chemical composition was investigated for the following size fractions obtained by crushing and screening the spent Li-ion battery after removing the stainless case; +425, 425 - 150, 150 - 125, 125 - 106 and 106 - 90μm. The products of the -150 μm size fraction obtained by crushing and screening after burning under a vacuum and removing the stainless case exhibit similar compositions. However, the +425 μm size fraction contains numerous foil-like materials. The separation of Al and Cu with a larger particle size by using a 425 μm sieve on the crushed product of the burned battery was carried out. It is important to separate the foil-like elements such as Al, Cu and Fe from the crushed products of the Li-ion battery using a sieve with a larger mesh size, for example 2-5 mm.
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