Patent 9187804 was granted and assigned to Sumitomo Metal Mining Co., Ltd. on November, 2015 by the United States Patent and Trademark Office.
To provide a lithium recovery method which is capable of efficiently recovering lithium without containing impurities, such as phosphorus and fluorine. In the present invention, an alkali is added to a discharge liquid and/or a cleaning liquid containing lithium discharged in a process of recovering valuable metals from a lithium ion battery, an acidic solvent extractant is caused to be in contact with the discharge liquid and/or the cleaning liquid under a condition of pH 9 or less and a temperature of 0 to 25° C. and lithium ions are extracted, and the acidic solvent extractant having extracted the lithium ions is caused to be in contact with an acid solution of pH 3 or less and the lithium ions are stripped.