Abstract: LiBF4 had become a hotspot in electrolyte research for Li-ion batteries because of its good thermal stability and moisture insensitivity.The properties of LiBF4 were introduced.The LiBF4 preparation methods，such as gas-solid reaction method，aqueous solution method，non-aqueous solvent method，and fluorine hydride solution method，were summarized.The LiBF4 characterization technologies，such as infrared spectroscopy analysis，X-ray diffraction analysis，ion-chromatographic analysis，thermal analysis，and electrochemical performance analysis，were stated.The direction on the research and development of LiBF4 for Li-ion battery was also put forward.

Key words: LiBF4, electrolyte, lithium ion battery