Electrochemical device and electronic device including same

Patent metadata

Field	Value
Publication number	US-2024356077-A1
Application number	US-202418758096-A
Country	US
Kind code	A1
Filing date	Jun 28, 2024
Priority date	Dec 31, 2021
Publication date	Oct 24, 2024
Grant date	—

Abstract

An electrochemical device includes: a negative electrode; a positive electrode, where the positive electrode includes a current collector and a positive electrode active material layer provided on the current collector, the positive electrode active material layer includes a positive electrode active material, and the positive electrode has an active specific surface area of X m2/g; and an electrolyte, where the electrolyte contains an additive A, the additive A contains LiPO2F2, and a weight percentage of the LiPO2F2 is Y % based on a weight of the electrolyte, where 0.005≤X/Y≤2 is satisfied. The electrochemical device has higher cycling performance, storage performance, and overcharge performance, as well as lower impedance.

First claim

What is claimed is:

1 . An electrochemical device, comprising:
a negative electrode; a positive electrode, wherein the positive electrode comprises a current collector and a positive electrode active material layer provided on the current collector, the positive electrode active material layer comprises a positive electrode active material, and the positive electrode has an active specific surface area of X m 2 /g; and an electrolyte, wherein the electrolyte contains an additive A, the additive A contains LiPO 2 F 2 , a weight percentage of the LiPO 2 F 2 is Y % based on a weight of the electrolyte, wherein 0.005≤X/Y≤2.

2 . The electrochemical device according to claim 1 , wherein at least one of the following conditions (i) to (iii) is satisfied:

0
.
0

⁢
1

≤
X
≤

0
.1

,

(
i
)

0.01
≤
Y
≤
2

;
or

(
ii
)

0.
5

≤

X
/
Y

≤
1.

(
iii
)

3 . The electrochemical device according to claim 1 , wherein the electrolyte further comprises vinylene carbonate, a weight percentage of the vinylene carbonate is Z % based on the weight of the electrolyte, wherein Z is 0.01 to 6.

4 . The electrochemical device according to claim 3 , wherein Z/Y is 0.01 to 600.

5 . The electrochemical device according to claim 1 , wherein the electrolyte further comprises fluoroethylene carbonate, and a weight percentage of the fluoroethylene carbonate is 0.01% to 5% based on the weight of the electrolyte.

6 . The electrochemical device according to claim 1 , wherein the electrolyte further comprises an additive B; and the additive B is at least one selected from the group consisting of lithium difluoro(oxalato)borate, lithium bis(oxalato)borate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium tetrafluoroborate, B 4 Li 2 O 7 , Li 3 BO 3 , CF 3 LiO 3 S, lithium hexafluorophosphate, and lithium perchlorate; and/or a weight percentage of the additive B is 0.01% to 16% based on the weight of the electrolyte.

7 . The electrochemical device according to claim 1 , wherein the positive electrode active material comprises element M; and the element M is at least one selected from the group consisting of Fe, Mn, Al, Ca, K, Na, Mg, Ti, and Zn.

8 . The electrochemical device according to claim 3 , wherein a weight of the vinylene carbonate is W1 g, a weight of the negative electrode is W2 g, and W1/W2 is 0.001 to 0.031.

9 . The electrochemical device according to claim 1 , wherein the electrolyte further comprises a compound containing an S═O functional group; and the compound containing the S═O functional group is at least one selected from the group consisting of 1,3-propane sultone, ethylene sulfate, methylene methyl disulfonate, propene sultone, 4-methylvinyl sulfate, 1,4-butane sultone, and 1,2,6-oxy-dithiane-2,2,6,6-tetroxide.

10 . The electrochemical device according to claim 9 , wherein a weight percentage of the compound containing the S═O functional group is 0.01% to 5% based on the weight of the electrolyte.

11 . An electronic device, wherein the electronic device comprises an electrochemical device, the electrochemical device comprises a negative electrode and a positive electrode; wherein
the positive electrode comprises a current collector and a positive electrode active material layer provided on the current collector, the positive electrode active material layer comprises a positive electrode active material, and the positive electrode has an active specific surface area of X m 2 /g; and an electrolyte, wherein the electrolyte contains an additive A, the additive A contains LiPO 2 F 2 , a weight percentage of the LiPO 2 F 2 is Y % based on a weight of the electrolyte, wherein 0.005≤X/Y≤2.

12 . The electronic device according to claim 11 , wherein at least one of the following conditions (i) to (iii) is satisfied:

0
.
0

⁢
1

≤
X
≤

0
.1

,

(
i
)

0.01
≤
Y
≤
2

;
or

(
ii
)

0.005
≤

X
/
Y

≤
1.

(
iii
)

13 . The electronic device a

Assignees

• Dongguan Amperex Tech Ltd

Inventors

• Xu Chunrui
• Xu Yanyan
• Tang Chao

Classifications

• H01M4/587

  for inserting or intercalating light metals · CPC title

• H01M2300/0025

  Organic electrolyte · CPC title

• H01M10/0569

  characterised by the solvents · CPC title

• H01M4/5825

  Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines · CPC title

• H01M10/0568

  characterised by the solutes · CPC title