Patents Assigned to Ishihara Sangoy Kaisha, Ltd.
  • Patent number: 6139815
    Abstract: Hydrogen lithium titanate prepared by an acid process of lithium titanate and having pH of 11.2 or smaller or hydrogen lithium titanate expressed by general formula H.sub.x Li.sub.y-x Ti.sub.z O.sub.4 (where y.gtoreq.x>0 0.8.ltoreq.y.ltoreq.2.7 and 1.3.ltoreq.z.ltoreq.2.2) is disclosed. Hydrogen lithium titanate may be employed as active materials of positive and negative electrodes of a non-aqueous electrolyte secondary battery thereby realizing a charging capacity greater than a theoretical capacity. It is preferable that hydrogen lithium titanate is formed into a particle shape and includes voids in the particles. It is preferable that the largest particle size is 0.1 .mu.m to 50 .mu.m and the specific surface area is 0.01 m.sup.2 /g to 300 m.sup.2 /g. Hydrogen lithium titanate of the foregoing type can be manufactured by bringing lithium titanate into contact with an acid, such as acetic acid, to substitute protons for lithium ions.
    Type: Grant
    Filed: July 14, 1999
    Date of Patent: October 31, 2000
    Assignees: Sony Corporation, Ishihara Sangoy Kaisha, Ltd.
    Inventors: Yoshinori Atsumi, Masayuki Nagamine, Hiromi Koga, Tokuo Suita