	US 11,901,545 B2
	Method for producing negative electrode active material particle
Takakazu Hirose, Annaka (JP); Takumi Matsuno, Annaka (JP); Reiko Sakai, Takasaki (JP); Kohta Takahashi, Takasaki (JP); and Hidekazu Awano, Takasaki (JP)
Assigned to SHIN-ETSU CHEMICAL CO., LTD., Tokyo (JP)
Filed by SHIN-ETSU CHEMICAL CO., LTD., Tokyo (JP)
Filed on Feb. 2, 2022, as Appl. No. 17/590,849.
Application 17/590,849 is a continuation of application No. 16/495,623, granted, now 11,283,060, previously published as PCT/JP2018/019271, filed on May 18, 2018.
Claims priority of application No. 2017-109468 (JP), filed on Jun. 1, 2017.
Prior Publication US 2022/0158166 A1, May 19, 2022
Int. Cl. H01M 4/02 (2006.01); H01M 4/36 (2006.01); H01M 4/62 (2006.01); H01M 4/48 (2010.01); H01M 4/38 (2006.01); H01M 4/131 (2010.01); H01M 4/1391 (2010.01); H01M 4/485 (2010.01); H01M 10/0525 (2010.01)

CPC H01M 4/131 (2013.01) [H01M 4/1391 (2013.01); H01M 4/485 (2013.01); H01M 10/0525 (2013.01); H01M 2004/027 (2013.01)]

1 Claim

1. A method for producing a negative electrode active material particle including a silicon compound particle, comprising the steps of:

preparing a silicon compound particle containing a silicon compound that contains oxygen;

inserting Li into the silicon compound particle; and

heating, while stirring, the Li-inserted silicon compound particle in a furnace to produce a negative electrode active material particle, wherein at least part of Si constituting the silicon compound particle after the heating is present in at least one state selected from an oxide of Si²⁺ to Si³⁺ containing no Li, and a compound containing Li and Si²⁺ to Si³⁺,

wherein the silicon compound particle has a peak or shoulder peak in an energy range from 1844 eV to 1846.5 eV in a XANES region of a Si K-edge in an X-ray absorption spectrum obtained when an X-ray absorption fine structure analysis is performed, and

wherein as the silicon compound particle is charged with electricity in a larger amount in an electricity charging process, the peak or shoulder peak appearing in the energy range from 1844 eV to 1846.5 eV in the XANES region of the Si K-edge has a higher intensity.