Lithium secondary battery

Patent metadata

Field	Value
Publication number	US-11205801-B2
Application number	US-201916573368-A
Country	US
Kind code	B2
Filing date	Sep 17, 2019
Priority date	Mar 28, 2019
Publication date	Dec 21, 2021
Grant date	Dec 21, 2021

Abstract

Disclosed is a lithium secondary battery having an improved lifetime. The lithium secondary battery may include: a cathode including a cathode active material; an anode including an anode active material; a separator disposed between the cathode and the anode; and an electrolyte including bis(trimethylsilyl) 2,2-thiodiacetate.

First claim

What is claimed is:

1. A lithium secondary battery comprising:
a cathode comprising a cathode active material;
an anode comprising an anode active material;
a separator disposed between the cathode and the anode; and
an electrolyte,
wherein the electrolyte comprises:
a lithium salt;
a solvent; and
an additive comprising bis(trimethylsilyl) 2,2-thiodiacetate.

2. The lithium secondary battery according to claim 1 , wherein a content of the bis(trimethylsilyl) 2,2-thiodiacetate is about 10 wt % or less (except for zero) with respect to the total weight of the electrolyte.

3. The lithium secondary battery according to claim 1 , wherein the content of the bis(trimethylsilyl) 2,2-thiodiacetate is within a range of about 0.3 wt % to 1.5 wt % with respect to the total weight of the electrolyte.

4. The lithium secondary battery according to claim 1 , wherein the additive further comprises one or more of vinylene carbonate (VC), trimethyl (phenyl) silane, and fluoroethylene carbonate (FEC).

5. The lithium secondary battery according to claim 4 , wherein a content of the trimethyl(phenyl)silane is about 10 wt % or less (except for zero) with respect to the total weight of the electrolyte.

6. The lithium secondary battery according to claim 4 , wherein the content of the trimethyl(phenyl)silane is within a range of about 0.5 wt % to 5 wt % with respect to the total weight of the electrolyte.

7. The lithium secondary battery according to claim 4 , wherein a content of each of the vinylene carbonate (VC) and the fluoroethylene carbonate (FEC) is within a range of about 0.5 wt % to 3 wt % with respect to the electrolyte.

8. The lithium secondary battery according to claim 4 , wherein a total content of the additive is within a range of about 0.5 wt % to 3.0 wt % with respect to the total weight of the electrolyte.

9. The lithium secondary battery according to claim 1 , wherein the lithium salt comprises one or more compounds selected from the group consisting of LiPF 6 , LiBF 4 , LiClO 4 , LiCl, LiBr, LiI, LiB 10 Cl 10 , LiCF 3 SO 3 , LiCF 3 CO 2 , LiAsF 6 , LiSbF 6 , LiAlCl 4 , CH 3 SO 3 Li, CF 3 SO 3 Li, LiN(SO 2 C 2 F 5 ) 2 , Li(CF 3 SO 2 ) 2 N, LiB(C 6 H 5 ) 4 , Li(SO 2 F) 2 N(LiFSI) and (CF 3 SO 2 ) 2 NLi.

10. The lithium secondary battery according to claim 1 , wherein the solvent comprises one or more compounds selected from the group consisting of ethylene carbonate (EC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), dimethyl carbonate (DMC), propylene carbonate (PC), dipropyl carbonate (DPC), butylene carbonate (BC), methyl propyl carbonate (MPC), and ethyl propyl carbonate (EPC).

11. The lithium secondary battery according to claim 1 , wherein the cathode active material comprises a lithium ternary (Ni—Mn—Co) cathode active material comprising nickel (Ni) in an amount of about 60 wt % to 99 wt % with respect to the total weight of the cathode active material.

12. The lithium secondary battery according to claim 1 , wherein the anode active material comprises a silicon-carbon composite.

13. The lithium secondary battery according to claim 12 , wherein the content of silicon in the silicon-carbon composite is about 5 wt % to 90 wt % with respect to the total weight of the anode active material.

14. A vehicle comprising a lithium secondary battery according to claim 1 .

Assignees

• Hyundai Motor Co Ltd
• Kia Motors Corp

Inventors

• Lee Yoon Sung
• Park Sangjin
• Kong Shinkook
• Cho Jung Young
• Kim Dongjun
• Kim Ikkyu
• Yeo Yeolmae
• Lee Jieun
• Park Sang Mok
• Lim Sunghoon

Classifications

• H01M10/0525

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

• H01M4/525 Primary

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title

• H01M2220/20

  Batteries in motive systems, e.g. vehicle, ship, plane · CPC title

• H01M2300/004

  Three solvents · CPC title

• H01M4/134

  Electrodes based on metals, Si or alloys · CPC title