Additive for non-aqueous electrolyte and secondary battery using the same

• US 20060263696A1
• Filed: 04/19/2006
• Published: 11/23/2006
• Est. Priority Date: 04/20/2005
• Status: Active Grant

• Current Assignee: LG Energy Solution Limited (LG Corporation)
• Original Assignee: LG Chem Limited (LG Corporation)
• Inventors: Kim, Yu Sin, Cha, Hye Yun, Kim, Hyeong Jin, Lee, Ho Chun
• Granted Patent: US 7,666,330 B2
• Time in Patent Office: Days
• US Class Current: 429/326
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/0567 characterised by the additives
• CPC Class Codes: H01M 10/0569 characterised by the solvents
• CPC Class Codes: H01M 10/4235 Safety or regulating additives or arrangements in electrodes, separators or electrolyte H01M10/4242 takes precedence
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

Disclosed is a compound represented by the following formula 1:

• • wherein, each of R¹˜R¹³ independently represents —H, —F, —Cl, —Br, —I, —OH, —SH, —COOH, —PO₃H₂, —NH₂, —NO₂, —O(CH₂CH₂O)_nH (wherein, n is an integer of 1˜5), C₁˜C₁₂ alkyl group, C₁˜C₁₂ aminoalkyl group, C₁˜C₁₂ hydroxyalkyl group, C₁˜C₁₂ haloalkyl group, C₂˜C₁₂ alkenyl group, C₁˜C₁₂ alkoxy group, C₁˜C₁₂ alkylamino group, C₁˜C₁₂ dialkylamino group, C₆˜C₁₈ aryl group, C₆˜C₁₈ aminoaryl group, C₆˜C₁₈ hydroxyaryl group, C₆˜C₁₈ haloaryl group, C₇˜C₁₈ benzyl group, C₇˜C₁₈ aminobenzyl group, C₇˜C₁₈ hydroxybenzyl group, C₇˜C₁₈ halobenzyl group, or nitrile group (—CN); and at least one of R⁴˜R¹³ is nitrile group (—CN). A non-aqueous electrolyte comprising: (i) a lithium salt, (ii) a solvent, and (iii) a compound represented by formula 1; and a secondary battery comprising the non-aqueous electrolyte are also disclosed. When the compound represented by formula 1 is added to a non-aqueous electrolyte, it is possible to improve the safety of a secondary battery in an overcharged state.

Claims

1. A compound represented by the following formula 1:

2. A non-aqueous electrolyte, which comprises:

(i) a lithium salt;

(ii) a solvent; and

(ii) a compound represented by the following formula 1;

wherein, each of R¹˜

R¹³ independently represents —

H, —

F, —

Cl, —

Br, —

I, —

OH, —

SH, —

COOH, —

PO₃H₂, —

NH₂, —

NO₂, —

O(CH₂CH₂O)_nH (wherein, n is an integer of 1˜

5), C₁˜

C₁₂ alkyl group, C₁˜

C₁₂ aminoalkyl group, C₁˜

C₁₂ hydroxyalkyl group, C₁˜

C₁₂ haloalkyl group, C₂˜

C₁₂ alkenyl group, C₁˜

C₁₂ alkoxy group, C₁˜

C₁₂ alkylamino group, C₁˜

C₁₂ dialkylamino group, C₆˜

C₁₈ aryl group, C₆˜

C₁₈ aminoaryl group, C₆˜

C₁₈ hydroxyaryl group, C₆˜

C₁₈ haloaryl group, C₇˜

C₁₈ benzyl group, C₇˜

C₁₈ aminobenzyl group, C₇˜

C₁₈ hydroxybenzyl group, C₇˜

C₁₈ halobenzyl group, or nitrile group (—

CN); and

at least one of R⁴˜

R¹³ is nitrile group (—

CN).

3. The non-aqueous electrolyte according to claim 2, wherein the compound represented by formula 1 is used in an amount of 0.5 wt %˜

10 wt % based on 100 wt % of the non-aqueous electrolyte.

4. The non-aqueous electrolyte according to claim 2, which further comprises cyclohexylbenzene or a derivative thereof.

5. The non-aqueous electrolyte according to claim 2, which further comprises a benzene derivative capable of forming a polymer.

6. The non-aqueous electrolyte according to claim 2, wherein the solvent includes at least one cyclic carbonate selected from the group consisting of ethylene carbonate (EC), propylene carbonate (PC), and gamma-butyrolactone (GBL);

and at least one linear carbonate selected from the group consisting of diethyl carbonate (DEC), dimethyl carbonate (DMC), ethylmethyl carbonate (EMC), and methyl propyl carbonate (MPC).

7. A secondary battery, comprising a cathode, an anode and a non-aqueous electrolyte, wherein the non-aqueous electrolyte comprises:

(i) a lithium salt;

(ii) a solvent; and

(ii) a compound represented by the following formula 1;

wherein, each of R¹˜

R¹³ independently represents —

H, —

F, —

Cl, —

Br, —

I, —

OH, —

SH, —

COOH, —

PO₃H₂, —

NH₂, —

NO₂, —

O(CH₂CH₂O)_nH (wherein, n is an integer of 1˜

5), C₁˜

C₁₂ alkyl group, C₁˜

C₁₂ aminoalkyl group, C₁˜

C₁₂ hydroxyalkyl group, C₁˜

C₁₂ haloalkyl group, C₂˜

C₁₂ alkenyl group, C₁˜

C₁₂ alkoxy group, C₁˜

C₁₂ alkylamino group, C₁˜

C₁₂ dialkylamino group, C₆˜

C₁₈ aryl group, C₆˜

C₁₈ aminoaryl group, C₆˜

C₁₈ hydroxyaryl group, C₆˜

C₁₈ haloaryl group, C₇˜

C₁₈ benzyl group, C₇˜

C₁₈ aminobenzyl group, C₇˜

C₁₈ hydroxybenzyl group, C₇˜

C₁₈ halobenzyl group, or nitrile group (—

CN); and

at least one of R⁴˜

R¹³ is nitrile group (—

CN).

8. The secondary battery according to claim 7, wherein the compound represented by formula 1 is used in an amount of 0.5 wt %˜

10 wt % based on 100 wt % of the non-aqueous electrolyte.

9. The secondary battery according to claim 7, wherein the non-aqueous electrolyte further comprises cyclohexylbenzene or a derivative thereof.

10. The secondary battery according to claim 7, wherein the non-aqueous electrolyte further comprises a benzene derivative capable of forming a polymer.

11. The secondary battery according to claim 7, wherein the solvent includes at least one cyclic carbonate selected from the group consisting of ethylene carbonate (EC), propylene carbonate (PC), and gamma-butyrolactone (GBL);

and at least one linear carbonate selected from the group consisting of diethyl carbonate (DEC), dimethyl carbonate (DMC), ethylmethyl carbonate (EMC), and methyl propyl carbonate (MPC).

12. The secondary battery according to claim 7, which is a lithium secondary battery.

13. The secondary battery according to claim 7, wherein the cathode comprises a lithium-containing transition metal oxide as a cathode active material.

14. A method for preparing a compound represented by the following formula 2, which is represented by the following reaction scheme 1:

15. A method for preparing a compound represented by the following formula 3, which is represented by the following reaction scheme 2:

16. A method for preparing a compound represented by the following formula 4, which is represented by the following reaction scheme 3: