Lithium ion secondary battery

Patent metadata

Field	Value
Publication number	US-2017005369-A1
Application number	US-201615171696-A
Country	US
Kind code	A1
Filing date	Jun 2, 2016
Priority date	Jun 30, 2015
Publication date	Jan 5, 2017
Grant date	—

Abstract

Provided is a lithium ion secondary battery including: a positive electrode; a negative electrode; a separator; and an electrolyte solution, the electrolyte solution including an additive A containing sulfur, and at least one of a cyclic carbonate additive B which is different from the additive A and which has an unsaturated bond and a cyclic carbonate additive C which is different from the additives A and B and which has a halogen. A molar ratio of the additive A relative to a total molar amount of the additive A, the additive B, and the additive C is smaller than a total of a molar ratio of the additive B and a molar ratio of the additive C relative to the total molar amount.

First claim

What is claimed is:

1 . A lithium ion secondary battery comprising:
a positive electrode; a negative electrode; a separator; and an electrolyte solution, the electrolyte solution including an additive A containing sulfur, and at least one of a cyclic carbonate additive B which is different from the additive A and which has an unsaturated bond and a cyclic carbonate additive C which is different from the additives A and B and which has a halogen, wherein a molar ratio of the additive A relative to a total molar amount of the additive A, the additive B, and the additive C is smaller than a total of a molar ratio of the additive B and a molar ratio of the additive C relative to the total molar amount.

2 . The lithium ion secondary battery according to claim 1 , wherein the molar ratio of the additive A is smaller than 50 mol %.

3 . The lithium ion secondary battery according to claim 1 , wherein both the additive B and the additive C are included.

4 . The lithium ion secondary battery according to claim 1 , wherein the additive A is a cyclic disulfonic acid ester compound.

5 . The lithium ion secondary battery according to claim 1 , wherein the additive B is vinylene carbonate.

6 . The lithium ion secondary battery according to claim 1 , wherein the additive C is 4-fluoroethylene carbonate.

7 . The lithium ion secondary battery according to claim 1 , wherein a positive electrode active material layer includes a transition metal composite oxide represented by general formula Li x Ni y Co z Me (1−y−z) O 2 (where Me is at least one kind of metal selected from the group consisting of Al, Mn, Na, Fe, Cr, Cu, Zn, Ca, K, Mg, and Pb, “x” is a numeral satisfying 1≦x≦1.2, “y” and “z” are positive numerals satisfying y+z<1, and “y” is a numeral of 0.5 or less).

8 . The lithium ion secondary battery according to claim 1 , wherein a weight of sulfur existing in the negative electrode is larger than a weight of sulfur existing in the positive electrode.

Assignees

• Automotive Energy Supply Corp

Inventors

• Nakagawa Takashi
• Yonehara Sayaka

Classifications

• H01M4/1391

  of electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M10/0525 Primary

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M10/0567 Primary

  characterised by the additives · CPC title

• H01M4/505

  of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy · CPC title

• H01M4/0404

  by coating on electrode collectors · CPC title