Method of extracting lithium with high purity from lithium bearing solution by electrolysis

A method of extracting high purity lithium from a lithium bearing solution by electrolysis comprising the steps of:

• preparing a lithium phosphate aqueous solution from the lithium bearing solution by adding a phosphorous supplying material;
• and
• extracting lithium from the lithium phosphate aqueous solution by electrolysis using an electrolytic device comprising an anode and a cathode separated from the anode by a cation exchange membrane,
• wherein the step of preparing a lithium phosphate aqueous solution from the lithium bearing solution by adding a phosphorous supplying material comprises the steps of:
• removing impurities comprising a step of adding an alkali in the lithium bearing solution to extract magnesium, boron or a mixture thereof and a step of adding an alkali, a carbonate or a mixture thereof in the lithium bearing solution from which magnesium and boron are extracted to extract calcium;
• extracting lithium phosphate by adding a phosphorous supplying material to the solution to precipitate lithium phosphate from the dissolved lithium;
• and
• preparing the lithium phosphate aqueous solution by dissolving the lithium phosphate in a phosphoric acid.