<Li> 1973--Adam Heller Proposes the lithium thionyl chloride battery, still used in implanted medical devices and in defense systems where greater than a 20 - year shelf life, high energy density, or extreme operating temperatures are encountered . </Li> <Li> 1977--Samar Basu demonstrated electrochemical intercalation of lithium in graphite at the University of Pennsylvania . This led to the development of a workable lithium intercalated graphite electrode at Bell Labs (LiC) to provide an alternative to the lithium metal electrode battery . </Li> <Li> 1979--Working in separate groups, at Stanford University Ned A. Godshall et al., and the following year in 1980 at Oxford University, England, John Goodenough and Koichi Mizushima, both demonstrated a rechargeable lithium cell with voltage in the 4 V range using lithium cobalt oxide (LiCoO) as the positive electrode and lithium metal as the negative electrode . This innovation provided the positive electrode material that made lithium batteries commercially possible . LiCoO is a stable positive electrode material which acts as a donor of lithium ions, which means that it can be used with a negative electrode material other than lithium metal . By enabling the use of stable and easy - to - handle negative electrode materials, LiCoO opened a whole new range of possibilities for novel rechargeable battery systems . Godshall et al. further identified in 1979, along with LiCoO, the similar value of ternary compound lithium - transition metal - oxides such as the spinel LiMn O, Li MnO, LiMnO, LiFeO, LiFe O, and LiFe O (and later lithium - copper - oxide and lithium - nickel - oxide cathode materials in 1985) </Li> <Li> 1980--Rachid Yazami demonstrated the reversible electrochemical intercalation of lithium in graphite . The organic electrolytes available at the time would decompose during charging with a graphite negative electrode, slowing the development of a rechargeable lithium / graphite battery . Yazami used a solid electrolyte to demonstrate that lithium could be reversibly intercalated in graphite through an electrochemical mechanism . (As of 2011, the graphite electrode discovered by Yazami is the most commonly used electrode in commercial lithium ion batteries). </Li>

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