Electrochemical device and electronic device containing same

Patent metadata

Field	Value
Publication number	US-2024372092-A1
Application number	US-202418778143-A
Country	US
Kind code	A1
Filing date	Jul 19, 2024
Priority date	Jan 21, 2022
Publication date	Nov 7, 2024
Grant date	—

Abstract

An electrochemical device includes a positive electrode, a negative electrode, and an electrolyte. The electrolyte includes a fluorine-substituted linear carboxylate ester. Based on a total mass of the electrolyte, a mass percent of the fluorine-substituted linear carboxylate ester is a %, satisfying: 10≤a≤70. The positive electrode includes a positive current collector and a positive active material layer applied onto at least one surface of the positive current collector. The positive active material layer includes a nickel-containing positive active material. Based on a total mass of the positive active material layer, a mass percent of nickel is x %, satisfying: 33≤x≤55. A coating weight of the positive active material applied on the positive current collector is w (mg/cm2), satisfying: 6.5≤w≤19.5, and 1.0≤a/w≤8.2.

First claim

What is claimed is:

1 . An electrochemical device, comprising a positive electrode, a negative electrode, and an electrolyte; wherein
the electrolyte comprises a fluorine-substituted linear carboxylate ester, and based on a total mass of the electrolyte, a mass percent of the fluorine-substituted linear carboxylate ester is a %, 10≤a≤70; the positive electrode comprises a positive current collector and a positive active material layer disposed on at least one surface of the positive current collector, the positive active material layer comprises a nickel-containing positive active material; and based on a total mass of the positive active material layer, a mass percent of nickel is x %, 33≤x≤55; and a coating weight of the positive active material disposed on the positive current collector is w (mg/cm 2 ), 6.5≤w≤19.5, and 1.0≤a/w≤8.2.

2 . The electrochemical device according to claim 1 , wherein the fluorine-substituted linear carboxylate ester comprises at least one of compounds represented by the following Formula I:

and
in Formula I, R 1 and R 2 each independently are an unsubstituted or fluorine-substituted C 1 to C 3 alkyl, and at least one of R 1 or R 2 is a fluorine-substituted C 1 to C 3 alkyl.

3 . The electrochemical device according to claim 2 , wherein the fluorine-substituted linear carboxylate ester comprises at least one of compounds represented by the following formulas:

4 . The electrochemical device according to claim 3 , wherein the electrolyte comprises a compound of Formula I-1 and a compound of Formula I-2; and, based on the total mass of the electrolyte, a mass percent of the compound of Formula I-1 is a 1 %, and a mass percent of the compound of Formula I-2 is a 2 %, and 10≤a 1 +a 2 ≤70.

5 . The electrochemical device according to claim 1 , wherein the electrolyte further comprises lithium bis(fluorosulfonyl)imide (LiFSI) as a lithium salt.

6 . The electrochemical device according to claim 5 , wherein a concentration of the LiFSI is c mol/L, and 0.3≤c≤1.2.

7 . The electrochemical device according to claim 5 , wherein a concentration of the LiFSI is c mol/L; a coating weight of the positive active material is w mg/cm 2 , and 0.04≤c/w≤0.18.

8 . The electrochemical device according to claim 1 , wherein the electrolyte further comprises a non-fluorinated cyclic carbonate ester, and the non-fluorinated cyclic carbonate ester comprises at least one of ethylene carbonate (EC) or propylene carbonate (PC).

9 . The electrochemical device according to claim 8 , wherein, based on the total mass of the electrolyte, a mass percent of the EC is b 1 %, and a mass percent of the PC is b 2 %; wherein 5≤b 1 +b 2 ≤40, and 0.2≤b 1 /b 2 ≤5.

10 . The electrochemical device according to claim 8 , wherein based on the total mass of the electrolyte, b 1 % is a mass percent of the EC and 0.1≤b 1 /x≤1.0.

11 . The electrochemical device according to claim 8 , wherein based on the total mass of the electrolyte, b 2 % is a mass percent of the PC; a coating weight of the positive active material denoted as w mg/cm 2 , and 0.3≤b 2 /w≤5.4.

12 . The electrochemical device according to claim 1 , wherein the electrolyte further satisfies at least one of the following conditions:
(1) the electrolyte comprises an unsaturated cyclic carbonate ester, based on the total mass of the electrolyte, a mass percent of the unsaturated cyclic carbonate ester is 0.1% to 5%; (2) the electrolyte comprises a fluorinated carbonate ester, based on the total mass of the electrolyte, a mass percent of the fluorinated carbonate ester is 0.1% to 5%; (3) the electrolyte comprises a cyclic sultone, based on the total mass of the electrolyte, a mass percent of the cyclic sultone is 0.1% to 5%; (4) the electrolyte comprises a cyclic sulfate lactone, based on the total mass of the electrolyte, a mass percent of the cyclic sulfate lactone is 0.1% to 5%; or (5) the electrolyte comprises a nitrile compound, based on the total mass of the electrolyte, a mass percent of the nitrile compound is 0.1% to 5%.

13 . The electrochemical device according to claim 12 , wherein the unsaturated cyclic carbonate ester comprises at least one of vinylene carbonate (VC) or vinyl ethylene carbonate (VEC), and the fluorinated carbonate ester comprises fluoroethylene carbonate (FEC);
the cyclic sultone comprises at least one of 1,3-propane sultone (PS), 1,4-butane sultone (BS), or 1,3-propene sultone (PST); the cyclic sulfate lactone comprises at least one of ethylene sulfate (DTD), propylene sulfate, or 4-methylethylene sulfate; and the nitrile compound comprises at least one of succinonitrile (SN), glutaronitrile, adiponitrile (ADN), 2-methyleneglutaronitrile, dipropylmalononitrile, 1,3,6-hexanetricarbonitrile (HTCN), 1,2,6-hexanetricarbonitrile, 1,3,5-pentanetricarbonitrile, or 1,2-bis(cyanoethoxy)ethane (EDPN).

14 . The electrochemical device according to claim 4 , wherein 40≤a 1 +a 2 ≤70.

15 . The electrochemical device according to claim 6 , wherein 0.5≤c≤1.2.

16 . The electrochemical device according to claim 7 , wherein 0.05≤c/w≤0.16.

17 . The electrochemical device according to claim 9 , wherein 10≤b 1 +b 2 ≤40 and 0.5≤b 1 /b 2 ≤5.

18 . The electrochemical device according to claim 10 , wherein 0.2≤b 1 /x≤0.8.

19 . The electrochemical device according to claim 11 , wherein 0.5≤b 2 /w≤5.0.

20 . An electronic device, wherein the electronic device comprises an electrochemical device, the electrochemical device comprises a positive electrode, a negative electrode, and an electrolyte; wherein
the electrolyte comprises a fluorine-substituted linear carboxylate ester, and based on a total mass of the electrolyte, a mass percent of the fluorine-substituted linear carboxylate ester is a %, 10≤a≤70; the positive electrode comprises a positive current collector and a positive active material layer disposed on at least one surface of the positive current collector, the positive active material layer comprises a nickel-containing positive active material; and based on a total mass of the positive active material layer, a mass percent of nickel is x %, 33≤x≤55; and a coating weight of the positive active material disposed on the positive current collector is w (mg/cm 2 ), 6.5≤w≤19.5, and 1.0≤a/w≤8.2.

Assignees

• Ningde Amperex Technology Ltd

Inventors

• Xu Yanyan

Classifications

• H01M2300/0034

  Fluorinated solvents · CPC title

• H01M4/131

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M2300/0037

  Mixture of solvents · CPC title

• H01M10/0525

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

• H01M10/0568

  characterised by the solutes · CPC title