Negative electrode active material, negative electrode, and secondary battery

1 . A negative electrode active material for a battery, comprising:

a negative electrode active material core material; and

a film provided on a surface of the negative electrode active material core material, wherein

the film includes an organic-inorganic hybrid film having a reactant at least including:

a first metal alkoxide including no metal atom-carbon atom bond in a molecule; and

a second metal alkoxide including two or more of metal atom-carbon atom bonds in a molecule;

the second metal alkoxide is a compound represented by a following general formula (2A), (2B), (2C), (2E) or (2F), or a mixture thereof:

(R 211 O), 3 Si—R 31 —Si(OR 212 ) 3   (2A)

wherein R 211 and R 212 each independently represent an alkyl group having 1 to 10 carbon atoms:

R 31 represents a divalent hydrocarbon group having 1 to 20 carbon atoms;

wherein R 211 , R 212 , R 213 , and R 214 each independently represent an alkyl group havig 1 to 10 carbon atoms;

R 32 represents a divalent hydrocarbon group having 1 to 20 carbon atoms;

R 33 represents a monovalent hydrocarbon group having 1 to 10 carbon atoms;

(R 211 ) 3 Si—R 34 —NH—R 35 —NH—R 36 —Si(OR 212 ) 3   (2C)

wherein R 211 and R 212 each independently represent an alkyl group having 1 to 10 carbon atoms;

R 34 , R 35 , and R 36 each independently represent a divalent hydrocarbon group having 1 to 10 carbon atoms;

wherein R 212 and R 213 each independently represent an alkyl group having 1 to 10 carbon atoms;

R 32 represents a divalent hydrocarbon group having 1 to 20 carbon atoms;

R 33 represents a monovalent hydrocarbon group having 1 to 10 carbon atoms:

and R 34 represents a monovalent hydrocarbon group having 1 to 30 carbon atoms;

wherein R 212 , R 213 , and R 214 each independently represent an alkyl group having 1 to 10 carbon atoms; and

wherein R 32 represents a divalent hydrocarbon group having 1 to 20 carbon atoms.

2 . The negative electrode active material according to claim 1 , wherein the first metal alkoxide includes a compound represented by a following general formula (1):

M 1 (OR 1 ) x   (1)

wherein, M 1 represents Si, Ti, Al, or Zr;

x represents the valence of M 1 and is an integer of 3 or 4; and

R 1 each independently represents an alkyl group having 1 to 10 carbon atoms or —C(R 2 )=CH—CO—R 3 , wherein R 2 represents an alkyl group having 1 to 10 carbon atoms, and R 3 represents an alkyl group having 1 to 30 carbon atoms, an alkyloxy group having 1 to 30 carbon atoms, or an alkenyloxy group having 1 to 30 carbon atoms.

3 . The negative electrode active material according to claim 1 , wherein the second metal alkoxide includes two or more Si atom-carbon atom bonds in the molecule.

4 . The negative electrode active material according to claim 2 , wherein the second metal alkoxide includes two or more Si atom-carbon atom bonds in the molecule.

5 . The negative electrode active material according to claim 1 , wherein the film comprises 10% by mass or more and 95% by mass or less of the first metal alkoxide and 5% by mass or more and 90% by mass or less of the second metal alkoxide with respect to a total amount of the film.

6 . The negative electrode active material according to claim 2 , wherein the film comprises 10% by mass or more and 95% by mass or less of the first metal alkoxide and 5% by mass or more and 90% by mass or less of the second metal alkoxide with respect to a total amount of the film.

7 . The negative electrode active material according to claim 3 , wherein the film comprises 10% by mass or more and 95% by mass or less of the first metal alkoxide and 5% by mass or more and 90% by mass or less of the second metal alkoxide with respect to a total amount of the film.

8 . The negative electrode active material according to claim 4 , wherein the film comprises 10% by mass or more and 95% by mass or less of the first metal alkoxide and 5% by mass or more and 90% by mass or less of the second metal alkoxide with respect to a total amount of the film.

9 . The negative electrode active material according to claim 1 , wherein the film comprises 10% by mass or more and 95% by mass or less of the first metal alkoxide and 5% by mass or more than 90% by mass or less of the second metal alkoxide with respect to a total amount of the film.

10 . The negative electrode active material according to claim 1 , wherein a content of the film is 0.20% by mass or more and 4.00% by mass or less with respect to a total amount of the negative electrode active material.

11 . The negative electrode active material according to claim 1 , wherein the negative electrode active material core material comprises at least Si.

12 . The negative electrode active material according to claim 1 , wherein the battery includes a lithium ion secondary battery.

13 . A negative electrode, comprising:

a negative electrode layer including the negative electrode active material according to claim 1 ; and

a negative electrode current collector.

14 . A secondary battery, comprising:

the negative electrode according to claim 13 ;

a positive electrode;

a separator provided between the positive electrode and the negative electrode; and

an electrolyte that are enclosed in an exterior body.

15 . The secondary battery according to claim 14 , wherein the electrolyte includes a nonaqueous electrolyte.

16 . The secondary battery according to claim 14 , wherein the positive electrode and the negative electrode are electrodes configured to receive and release lithium ions.

17 . The secondary battery according to claim 15 , wherein the positive electrode and the negative electrode are electrodes configured to receive and release lithium ions.

18 . A method of making the negative electrode active material according to claim 1 , the method comprising stirring a negative electrode active material core material together with a first metal alkoxide and a second metal alkoxide in an alkaline solvent.