Method for producing secondary battery including coating on electrode surface

Patent metadata

Field	Value
Publication number	US-10797350-B2
Application number	US-201615765905-A
Country	US
Kind code	B2
Filing date	Oct 5, 2016
Priority date	Oct 5, 2015
Publication date	Oct 6, 2020
Grant date	Oct 6, 2020

Abstract

A method for producing a secondary battery including:
an electrolytic solution containing a metal salt whose cation is an alkali metal, an alkaline earth metal, or aluminum and whose anion has a chemical structure represented by general formula (1) below, and a linear carbonate represented by general formula (2) below; a negative electrode; a positive electrode; and a coating on a surface of the negative electrode and/or the positive electrode, the coating containing S, O, and C, the method including forming the coating by performing a specific activation process on a secondary battery including the electrolytic solution, the negative electrode, and the positive electrode,

(R 1 X 1 )(R 2 SO 2 )N  general formula (1),

R 20 OCOOR 21   general formula (2).

First claim

The invention claimed is:

1. A method for producing a secondary battery,
the method comprises
providing a negative electrode, a positive electrode, and an electrolytic solution, and
forming a coating containing S, O, and C on a surface of a negative electrode and/or a positive electrode by performing, on the negative electrode, the positive electrode, and the electrolytic solution, an activation process including step (a), step (b), and step (c) below, or step (a) and step (d) below,
(a) step of performing charging to a second voltage V 2 in step (a-1) or step (a-2) below,
(a-1) step of continuously performing charging at a first rate C 1 to a first voltage V 1 and then performing charging at a second rate C 2 to the second voltage V 2 where V 1 <V 2 , and C 1 <C 2 ,
(a-2) step of performing charging at a constant charging rate C a-2 of 1 C or higher to the second voltage V 2 ,

(b) step of discharging the secondary battery having been subjected to step (a), at a third rate C 3 to a third voltage V 3 or lower,
(c) step of performing charging and discharging at a fourth rate C 4 between the third voltage V 3 and the second voltage V 2 ,
(d) step of keeping the temperature of the secondary battery in a range of 40 to 120° C.,
wherein the electrolytic solution contains a metal salt whose cation is an alkali metal, an alkaline earth metal, or aluminum and whose anion has a chemical structure represented by general formula (1) below, and a linear carbonate represented by general formula (2) below, the linear carbonate being contained by not less than 90 vol % relative to an entire organic solvent, a mole ratio of the linear carbonate relative to the metal salt being 2 to 6,
(R 1 X 1 )(R 2 SO 2 )N  general formula (1)

(R 1 is selected from: hydrogen; a halogen; an alkyl group optionally substituted with a substituent group; a cycloalkyl group optionally substituted with a substituent group; an unsaturated alkyl group optionally substituted with a substituent group; an unsaturated cycloalkyl group optionally substituted with a substituent group; an aromatic group optionally substituted with a substituent group; a heterocyclic group optionally substituted with a substituent group; an alkoxy group optionally substituted with a substituent group; an unsaturated alkoxy group optionally substituted with a substituent group; a thioalkoxy group optionally substituted with a substituent group; an unsaturated thioalkoxy group optionally substituted with a substituent group; CN; SCN; or OCN,
R 2 is selected from: hydrogen; a halogen; an alkyl group optionally substituted with a substituent group; a cycloalkyl group optionally substituted with a substituent group; an unsaturated alkyl group optionally substituted with a substituent group; an unsaturated cycloalkyl group optionally substituted with a substituent group; an aromatic group optionally substituted with a substituent group; a heterocyclic group optionally substituted with a substituent group; an alkoxy group optionally substituted with a substituent group; an unsaturated alkoxy group optionally substituted with a substituent group; a thioalkoxy group optionally substituted with a substituent group; an unsaturated thioalkoxy group optionally substituted with a substituent group; CN; SCN; or OCN,
R 1 and R 2 optionally bind with each other to form a ring,
X 1 is selected from SO 2 , C═O, C═S, R a P═O, R b P═S, S═O, or Si═O,
R a and R b are each independently selected from: hydrogen; a halogen; an alkyl group optionally substituted with a substituent group; a cycloalkyl group optionally substituted with a substituent group; an unsaturated alkyl group optionally substituted with a substituent group; an unsaturated cycloalkyl group optionally substituted with a substituent group; an aromatic group optionally substituted with a substituent group; a heterocyclic group optionally substituted with a substituent group; an alkoxy group optionally substituted with a substituent group; an unsaturated alkoxy group optionally substituted with a substituent group; a thioalkoxy group optionally substituted with a substituent group; an unsaturated thioalkoxy group optionally substituted with a substituent group; OH; SH; CN; SCN; or OCN,
R a and R b each optionally bind with R 1 or R 2 to form a ring),
R 20 OCOOR 21   general formula (2)

(R 20 and R 21 are each independently selected from C n H a F b Cl c Br d I e that is a linear alkyl, or C m H f F g Cl h Br i I j that includes a cyclic alkyl in the chemical structure thereof, “n” is an integer not smaller than 1, “m” is an integer not smaller than 3, and “a”, “b”, “c”, “d”, “e”, “f”, “g”, “h”, “i”, and “j” are each independently an integer not smaller than 0, and satisfy 2n+1=a+b+c+d+e and 2m−1=f+g+h+i+j).

2. A method for producing a secondary battery,
providing a negative electrode, a positive electrode, and an electrolytic solution, and
forming a coating containing S, O, and C on a surface of a negative electrode and/or a positive electrode by performing, on the negative electrode, the positive electrode, and the electrolytic solution, an activation process including step (a), step (b), and step (c) below, or step (a) and step (d) below,
(a) step of performing charging to a second voltage V 2 in step (a-1) or step (a-2) below,
(a-1) step of continuously performing charging at a first rate C 1 to a first voltage V 1 and then performing charging at a second rate C 2 to the second voltage V 2 where V 1 <V 2 , and C 1 <C 2 ,
(a-2) step of performing charging at a constant charging rate C a-2 of 2C or higher to the second voltage V 2 ,

(b) step of discharging the secondary battery having been subjected to step (a), at a third rate C 3 to a third voltage V 3 or lower,
(c) step of performing charging and discharging at a fourth rate C 4 between the third voltage V 3 and the second voltage V 2 ,
(d) step of keeping the temperature of the secondary battery in a range of 40 to 120° C.,
wherein the electrolytic solution contains a metal salt whose cation is an alkali metal, an alkaline earth metal, or aluminum and whose anion has a chemical structure represented by general formula (1) below, and a linear carbonate represented by general formula (2) below, the linear carbonate being contained by not less than 90 vol % relative to an entire organic solvent, a mole ratio of the linear carbonate relative to the metal salt being 2 to 6,
(R 1 X 1 )(R 2 SO 2 )N  general formula (1)

(R 1 is selected from: hydrogen; a halogen; an alkyl group optionally substituted with a substituent group; a cycloalkyl group optionally substituted with a substituent group; an unsaturated alkyl group optionally substituted with a substituent group; an unsaturated cycloalkyl group optionally substituted with a substituent group; an aromatic group optionally substituted with a substituent group; a heterocyclic group optionally substituted with a substituent group; an alkoxy group optionally substituted with a substituent group; an unsaturated alkoxy group optionally substituted with a substituent group; a thioalkoxy group optionally substituted with a substituent group; an unsaturated thioalkoxy group optionally substituted with a substituent group; CN; SCN; or OCN,
R 2 is selected from: hydrogen; a halogen; an alkyl group optionally substituted with a substituent group; a cycloalkyl group optionally substituted with a substituent group; an unsaturated alkyl group optionally substituted with a substituent group; an unsaturated cycloalkyl group optionally substituted with a substituent group; an aromatic group optionally substituted with a substituent group; a heterocyclic group optionally substituted with a substituent group; an alkoxy group optionally substituted with a substituent group; an unsaturated alkoxy group optionally substituted with a substituent group;

Assignees

• Toyota Jidoshokki Kk

Inventors

• Sasaki Hiroyuki
• Kawai Tomoyuki
• Nakagaki Yoshihiro
• Aikiyo Hitoshi
• Maki Takeshi

Classifications

• Y02P70/50

  Manufacturing or production processes characterised by the final manufactured product · CPC title

• H01M2300/0028

  characterised by the solvent · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• H01M10/0525

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

• H01M10/049

  Processes for forming or storing electrodes in the battery container · CPC title