Lithium secondary battery

Patent metadata

Field	Value
Publication number	US-9831526-B2
Application number	US-201314439743-A
Country	US
Kind code	B2
Filing date	Oct 29, 2013
Priority date	Oct 30, 2012
Publication date	Nov 28, 2017
Grant date	Nov 28, 2017

Abstract

The present invention provides a lithium secondary battery, wherein a peak at 167 to 171 eV and a peak at 160 to 164 eV are present in XPS analysis of sulfur on a negative electrode surface (S2p), and P169/P162 is in the range of 0.7 to 2.0 wherein the P169/P162 is the ratio between the intensity of the peak at 167 to 171 eV (P169) and the intensity of the peak at 160 to 164 eV (P162).

First claim

The invention claimed is:

1. A lithium secondary battery comprising:
a negative electrode comprising a carbon material comprising a composite carbon material formed by coating a surface of an amorphous carbon with artificial graphite, and
an electrolyte solution comprising methylene methane disulfonate, and
wherein a peak at 167 to 171 eV and a peak at 160 to 164 eV are present in XPS analysis of sulfur (S2p) of a negative electrode surface, and P169/P162 is in the range of 0.7 to 2.0 wherein the P169/P162 is the ratio between the intensity of the peak at 167to 171 eV (P169) and the intensity of the peak at 160 to 164 eV (P162).

2. A method for producing a lithium secondary battery comprising a positive electrode, a negative electrode, and an electrolyte solution comprising methylene methane disulfonate, comprising:
a step of producing an electrode element by arranging the positive electrode and the negative electrode to face each other; and
a step of enclosing the electrode element, and the electrolyte solution comprising an additive comprising the methylene methane disulfonate, and a non-aqueous electrolytic solvent in an outer package, and performing charging;
whereby a peak at 167 to 171 eV and a peak at 160 to 164 eV are present in XPS analysis of sulfur (S2p) of a negative electrode surface, and P169/P162 is in the range of 0.7 to 2.0 wherein the P169/P162 is the ratio between the intensity of the peak at 167 to 171 eV (P169) and the intensity of the peak at 160 to 164 eV (P162); and
wherein the negative electrode comprises a carbon material comprising a composite carbon material formed by coating a surface of an amorphous carbon with artificial graphite.

3. The method of producing a lithium secondary battery according to claim 2 , wherein the charging is performed at a temperature of 39° C. or more and constant charging current until the upper limit voltage is reached is in the range of 0.1 C to 0.5 C.

4. The lithium secondary battery according to claim 1 , wherein the carbon material comprises a composite carbon material formed by coating a surface of hard carbon with artificial graphite.

Assignees

• Nec Corp

Inventors

• Iriyama Jiro

Classifications

• H01M10/0567 Primary

  characterised by the additives · CPC title

• H01M10/058

  Construction or manufacture · CPC title

• H01M10/0525

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

• H01M4/587

  for inserting or intercalating light metals · CPC title

• H01M4/133

  Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx · CPC title