Lithium ion secondary battery
Provided is a lithium ion secondary battery including: a positive electrode having a positive electrode active material layer disposed on a positive electrode current collector; a negative electrode having a negative electrode active material layer disposed on a negative electrode current collector; a separator; and an electrolyte solution. The positive electrode active material layer includes a positive electrode active material containing lithium nickel composite oxide. The electrolyte solution contains a disulfonic acid compound as an additive. A mass of the disulfonic acid compound adsorbed on the positive electrode is 1.0 g/m 2 or less per unit surface area of the lithium nickel composite oxide.
1. A lithium ion secondary battery comprising:
a positive electrode having a positive electrode active material layer disposed on a positive electrode current collector;
a negative electrode having a negative electrode active material layer disposed on a negative electrode current collector;
a separator; and
an electrolyte solution, wherein
the positive electrode active material layer includes a positive electrode active material containing lithium nickel cobalt manganese composite oxide having a layered crystal structure and is represented by a general formula Li x Ni y Co z Mn (1-y-z) O 2 in which x satisfies 1≤x≤1.2, y and z are positive numerals satisfying y+z<1, and y is 0.5 or less and greater than 0,
the electrolyte solution contains a disulfonic acid compound as an additive,
the disulfonic acid compound is selected from the group consisting of methanedisulfonic acid, 1,2-ethanedisulfonic acid, 1,3-propanedisulfonic acid, 1,4-butanedisulfonic acid, benzenedisulfonic acid, naphthalenedisulfonic acid, and biphenyldisulfonic acid, and
a mass of the disulfonic acid compound adsorbed on the positive electrode is 0.01 g/m 2 or more and 1.0 g/m 2 or less per unit surface area of the lithium nickel cobalt manganese composite oxide.
2. The lithium ion secondary battery according to claim 1 , wherein the disulfonic acid compound is naphthalenedisulfonic acid.
3. The lithium ion secondary battery according to claim 1 , wherein the disulfonic acid compound is methanedisulfonic acid.
4. The lithium ion secondary battery according to claim 1 , wherein the disulfonic acid compound is 1,2-ethanedisulfonic acid.
5. The lithium ion secondary battery according to claim 1 , wherein the disulfonic acid compound is 1,3-propanedisulfonic acid.
6. The lithium ion secondary battery according to claim 1 , wherein the disulfonic acid compound is 1,4-butanedisulfonic acid.
7. The lithium ion secondary battery according to claim 1 , wherein the disulfonic acid compound is benzenedisulfonic acid.
8. The lithium ion secondary battery according to claim 1 , wherein the disulfonic acid compound is biphenyldisulfonic acid.
9. The lithium ion secondary battery according to claim 1 , wherein a sulfonic acid groups of the disulfonic acid compound forms a salt with lithium ion.
10. The lithium ion secondary battery according to claim 1 , wherein
the electrolyte solution further contains as an additive, a cyclic carbonate compound with an unsaturated bond and/or a cyclic carbonate compound with a halogen, and
a total mass of the cyclic carbonate compound with the unsaturated bond and the cyclic carbonate compound with the halogen contained in the electrolyte solution per unit surface area of the lithium nickel composite oxide is more than the mass of the disulfonic acid compound adsorbed on the positive electrode per unit surface area of the lithium nickel composite oxide.
11. The lithium ion secondary battery according to claim 1 , a capacity of the lithium ion secondary battery is 5 Ah or more and 70 Ah or less.
12. The lithium ion secondary battery according to claim 1 , wherein the a general formula Li x Ni y Co z Mn (1-y-z) O 2 satisfies 1−y−z≤0.4.
13. The lithium ion secondary battery according to claim 1 , wherein the a general formula Li x Ni y Co z Mn (1-y-z) O 2 satisfies z<y and z<1−y−z.
14. The lithium ion secondary battery according to claim 1 , wherein the a general formula Li x Ni y Co z Mn (1-y-z) O 2 satisfies y>1−y−z and y>z.
15. The lithium ion secondary battery according to claim 1 , wherein
the positive electrode active material layer further includes a positive electrode active material containing LiMn 2 O 4 .
16. The lithium ion secondary battery according to claim 1 , wherein the content of water relative to the weight of the lithium nickel cobalt manganese composite oxide in the positive electrode active material is 400 ppm.
17. The lithium ion secondary battery according to claim 1 , wherein the separator includes an olefin resin layer.
18. The lithium ion secondary battery according to claim 17 , wherein the olefin resin layer comprises porous or microporous polyolefin.
19. The lithium ion secondary battery according to claim 1 , wherein the negative electrode active material layer comprises at least one material selected from the group consisting of carbon nanofiber, acetylene black, Ketjen black, activated carbon, mesoporous carbon, fullerenes, and carbon nanotube.
20. The lithium ion secondary battery according to claim 1 , wherein the negative electrode active material layer comprises at least one binder selected from the group consisting of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), polyvinyl fluoride (PVF), polyanilines, polythiophenes, polyacetylenes, polypyrroles, styrene butadiene rubber (SBR), butadiene rubber (BR), chloroprene rubber (CR), isoprene rubber (IR), acrylonitrile butadiene rubber (NBR), carboxymethyl cellulose (CMC), xanthan gum, guar gum, and pectin.