Patent ID: 8052897

Claim:
A cathode active material comprising a mixed crystal, the mixed crystal having: a first crystalline substance having one or more members with the general formulas Li xx M′ yy (XO 4 ) zz , LiM′XO 5 , LiM′XO 6 and LiM′X 2 O 7 , wherein: 0<xx/zz≦1 and 0<yy/zz≦1; M′ is selected from elements Na, Mn, Fe, Co, Ni, Ti, Nb and V; X is selected from elements P, S, As, Mo and W; and a second crystalline substance having one or more members with the general formulas LiD c O 2 , Li i Ni 1-d-e Co d Mn e O 2 , LiNi 1-f-g Co f Al g O 2 , Li x Ni 1-y CoO 2 , Li a M b Mn 2-b O 4 and Li m Mn 2-n E n O j , wherein: D is selected from elements B, Mg, Al, Ti, Cr, Fe, Cu, Zn, Ga, Y, La and V; 0<c≦3, 0.9≦i≦1.2, 0≦d≦0.5, 0≦e≦0.3, 0≦f≦0.5, 0≦g≦0.3, 0.9≦x≦1.1 and 0≦y≦1; M is selected from elements boron, magnesium, aluminum, titanium, chromium, iron, cobalt, nickel, copper, zinc, gallium and yttrium; 0.9≦a≦1.2 and 0≦b≦1; E includes one or more transition metals; and 0.9≦m≦1.1, 0≦n≦1 and 1<j<6, wherein the first crystalline substance has a lattice, and at least a part of the second crystalline substance is received by and distributed in the lattice of the first crystalline structure.