Electrolyte additive for lithium secondary battery and lithium secondary battery including the same

Patent metadata

Field	Value
Publication number	US-11329318-B2
Application number	US-201916682804-A
Country	US
Kind code	B2
Filing date	Nov 13, 2019
Priority date	Jan 3, 2019
Publication date	May 10, 2022
Grant date	May 10, 2022

Abstract

Disclosed herein is an additive for a lithium secondary battery, the additive including a compound represented by Formula 1. An electrolyte for a lithium secondary battery includes: a lithium salt; a non-aqueous organic solvent; and the additive represented by Formula 1. A lithium secondary battery includes: a cathode; an anode; and the electrolyte including the additive represented by Formula 1.

First claim

What is claimed is:

1. An additive for an electrolyte of a lithium secondary battery,
the additive comprising a compound represented by Formula 1:

in Formula 1,
X 1 is N(R 9 ), O, or S,
b1 is selected from an integer of 0 to 3, L 1 and L 2 are directly connected to each other when b1 is 0, and the X 1 's are the same as or different from each other when b1 is 2 or more,
L 1 and L 2 are each independently selected from a substituted or unsubstituted C 1 -C 30 alkyl group, a substituted or unsubstituted C 2 -C 30 alkenyl group, a substituted or unsubstituted C 2 -C 30 alkynyl group, and a substituted or unsubstituted C 2 -C 30 alkoxyalkyl group, and a substituted or unsubstituted C 1 -C 30 alkylamine group,
a1 and a2 are each independently selected from an integer of 0 to 10, the L 1 's are the same as or different from each other when a1 is 2 or more, the L 2 's are the same as or different from each other when a2 is 2 or more, and a1+a2 is 1 or more,
R 1 to R 9 are each independently selected from a substituted or unsubstituted C 1 -C 30 alkyl group, a substituted or unsubstituted C 2 -C 30 alkenyl group, and a substituted or unsubstituted vinyl group, and
substituents of the substituted C 1 -C 30 alkyl group, the substituted C 2 -C 30 alkenyl group, the substituted C 2 -C 30 alkynyl group, the substituted C 2 -C 30 alkoxyalkyl group, the substituted C 1 -C 30 alkylamine group, and the substituted vinyl group are at least one selected from a C 1 -C 20 alkyl group, a C 2 -C 20 alkenyl group, a C 2 -C 20 alkynyl group, a C 1 -C 20 alkoxy group, a vinyl group, a halogen, a cyano group, a hydroxyl group, and a nitro group.

2. The additive of claim 1 , wherein,
in Formula 1, L 1 and L 2 are each independently selected from:
a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, and a heptylene group; and
a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, and a heptylene group, each of which is substituted with at least one selected from a methyl group, an ethyl group, a propyl group, a vinyl group, —F, —Cl, —Br, —I, a cyano group, a hydroxyl group, and a nitro group.

3. The additive of claim 1 , wherein,
in Formula 1, a1+a2 is 1 or 2.

4. The additive of claim 1 , wherein,
in Formula 1,
i) b1 is 0, each of a1 and a2 is 1, and each of L 1 and L 2 is a methylene group,
ii) b1 is 0, a1 is 1, a2 is 0, and L 1 is an ethylene group,
iii) b1 is 0, a1 is 2, a2 is 0, and L 1 is a methylene group,
iv) b1 is 0, a1 is 0, a2 is 1, and L 2 is an ethylene group, or
v) b1 is 0, a1 is 0, a2 is 2, and L 2 is a methylene group.

5. The additive of claim 1 , wherein,
in Formula 1, R 1 to R 9 are each independently selected from:
a C 1 -C 30 alkyl group, a vinyl group, an a C 1 -C 30 alkyl group substituted with at least one selected from a methyl group, an ethyl group, a propyl group, a butyl group, —F, —Cl, —Br, —I, a cyano group, a hydroxy group, and a nitro group.

6. The additive of claim 1 , wherein,
in Formula 1, each of R 1 to R 9 is a C 1 -C 30 alkyl group.

7. The additive of claim 1 , wherein,
the compound represented by Formula 1 is Compound 1:

8. An electrolyte for a lithium secondary battery, comprising:
a lithium salt;
a non-aqueous organic solvent; and
the additive according to claim 1 .

9. The electrolyte of claim 8 , wherein,
an amount of the additive is in a range of about 0.1 wt % to about 3 wt % based on a total weight of the electrolyte.

10. The electrolyte of claim 8 , wherein,
an amount of the additive is in a range of about 0.1 wt % to about 2 wt % based on a total weight of the electrolyte.

11. The electrolyte of claim 8 , wherein,
the lithium salt comprises at least one selected from LiPF 6 , LiBF 4 , LiSbF 6 , LiAsF 6 , LiClO 4 , LiCF 3 SO 3 , Li(CF 3 SO 2 ) 2 N, LiC 4 F 9 SO 3 , LiAlO 2 , LiAlCl 4 , LiN(C x F 2x+1 SO 2 )(C y F 2y+1 SO 2 ) (0≤x≤20, 0≤y≤20), LiCl, LiI, lithium bis(oxalate) borate (LiBOB), and LiPO 2 F 2 .

12. The electrolyte of claim 8 , wherein,
the non-aqueous organic solvent comprises at least one selected from ethyl methyl carbonate (EMC), methyl propyl carbonate, ethyl propyl carbonate, dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate, propylene carbonate (PC), ethylene carbonate (EC), fluoroethylene carbonate (FEC), vinylene carbonate (VC), vinylethylene carbonate (VEC), butylene carbonate, ethyl propionate, ethyl butyrate, dimethyl sulfoxide, dimethyl formamide, dimethylacetamide, gamma-valerolactone, gamma-butyrolactone, and tetrahydrofuran.

13. A lithium secondary battery, comprising:
a cathode;
an anode; and
the electrolyte of claim 8 .

14. The lithium secondary battery of claim 13 , wherein,
the cathode comprises a cathode active material having a layered structure.

15. The lithium secondary battery of claim 14 , wherein,
the cathode active material is represented by Formula 3:
LiNi 1−s M′ s O 2   Formula 3

wherein, in Formula 3,
M′ is at least one selected from Co, Mn, Al, Cu, Fe, Mg, Cr, Zn, B, and Ga, and
0<s≤0.99 is satisfied.

16. The lithium secondary battery of claim 14 , wherein,
the cathode active material is represented by Formula 4:
Li t (Ni 1−u−v Co u M″ v )O 2   Formula 4

wherein, in Formula 4,
M″ is Mn or Al, and 0.96≤t≤1.05, 0<u≤0.5, and 0<v≤0.5 are satisfied.

Assignees

• Samsung Sdi Co Ltd

Inventors

• Cho Wonseok
• Shatunov Pavel
• TSAY Olga
• Kang Younghye
• Kim Aeran
• Park Hyejin
• Woo Myungheui
• You Duckjae
• Lee Taejin
• Lee Harim
• Lim Jinhyeok
• Choi Hyunbong

Classifications

• H01M10/0568

  characterised by the solutes · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• H01M10/0525

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

• H01M2300/0025

  Organic electrolyte · CPC title

• C07F7/10 Primary

  containing nitrogen {having a Si-N linkage} · CPC title