NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY
In a non-aqueous electrolyte secondary battery, a first active material of a positive electrode includes at least one of carbon-coated LiFePO 4 , LiMnPO 4 and Li 3 V 2 (PO 4 ) 3 . A second active material of the positive electrode includes lithium nickel composite oxide. An electrolytic solution includes fluorinated ethylene carbonate.
1 . A non-aqueous electrolyte secondary battery comprising:
a first active material of a positive electrode including a chemical compound represented by a formula of LiFePO 4 , LiMnPO 4 or Li 3 V 2 (PO 4 ) 3 or a chemical compound in which a part of a site of Fe, Mn or V in the formula of LiFePO 4 , LiMnPO 4 or Li 3 V 2 (PO 4 ) 3 is substituted by a different metallic element having an atomic number of 11 or more, wherein the chemical compound is coated with a conductive carbon;
a second active material of the positive electrode including lithium nickel composite oxide; and
an electrolytic solution including fluorinated ethylene carbonate.
2 . The non-aqueous electrolyte secondary battery according to claim 1 , wherein the second active material comprises lithium nickel cobalt composite oxide.
3 . The non-aqueous electrolyte secondary battery according to claim 2 , wherein an amount of nickel contained in the second active material is 0.3 to 0.8 moles with respect to one mole of a Li atom.
4 . The non-aqueous electrolyte secondary battery according to claim 3 , wherein the second active material comprises LiNi 0.8 Co 0.1 Mn 0.1 O 2 and a content of LiNi 0.8 Co 0.1 Mn 0.1 O 2 in the positive electrode is 10 to 80 parts by mass.
5 . The non-aqueous electrolyte secondary battery according to claim 3 , wherein the second active material comprises LiNi 0.8 Co 0.2 Mn 0.2 O 2 and a content of LiNi 0.6 Co 0.2 Mn 0.2 O 2 in the positive electrode is 15 to 85 parts by mass.
6 . The non-aqueous electrolyte secondary battery according to claim 3 , wherein the second active material comprises LiNi 0.3 Co 0.3 Mn 0.4 O 2 and a content of LiNi 0.3 Co 0.3 Mn 0.4 O 2 in the positive electrode is 50 to 85 parts by mass.
7 . The non-aqueous electrolyte secondary battery according claim 1 , wherein a content of the fluorinated ethylene carbonate in the electrolytic solution is 0.2% by mass to 10% by mass.