Non-aqueous electrolytic solution and lithium secondary battery

• US 20020001756A1
• Filed: 05/25/2001
• Published: 01/03/2002
• Est. Priority Date: 05/25/2000
• Status: Abandoned Application

• Current Assignee: UBE Industries Limited
• Original Assignee: UBE Industries Limited
• Inventors: Abe, Koji, Hamamoto, Toshikazu, Ueki, Akira
• Application Number:
  US09/865,608
• Publication Number:
  US 20020001756A1
• Time in Patent Office: Days
• US Class Current: 429/324
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/0567 characterised by the additives
• CPC Class Codes: H01M 2300/0037 Mixture of solvents
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A non-aqueous electrolytic solution favorably employable for a lithium secondary battery employs a non-aqueous electrolytic solution which comprises a non-aqueous solvent and an electrolyte which further contains 0.001 to 0.8 weight % of a biphenyl derivative having the formula:

in which each of Y¹ and Y² represents hydroxyl, alkoxy, hydrocarbyl, hydrogen, acyloxy, alkoxycarbonyloxy, alkylsulfonyloxy, or halogen, and each of p and q is an integer of 1 to 3.

Claims

1. A non-aqueous electrolytic solution which comprises a non-aqueous solvent and an electrolyte which further contains 0.001 to 0.8 weight % of a biphenyl derivative having the following formula:

2. The non-aqueous electrolytic solution of claim 1, wherein the biphenyl derivative has the following formula:

3. The non-aqueous electrolytic solution of claim 1, wherein the amount of the biphenyl derivative is in the range of 0.01 to 0.5 weight %.

4. The non-aqueous electrolytic solution of claim 2, wherein the amount of the biphenyl derivative is in the range of 0.01 to 0.5 weight %.

5. The non-aqueous electrolytic solution of claim 1, wherein the non-aqueous solvent comprises a combination of a cyclic carbonate and a linear chain carbonate.

6. The non-aqueous electrolytic solution of claim 2, wherein the non-aqueous solvent comprises a combination of a cyclic carbonate and a linear chain carbonate

7. The non-aqueous electrolytic solution of claim 1, wherein the non-aqueous solvent comprises a high dielectric constant solvent which is selected from the group consisting of ethylene carbonate, propylene carbonate, and butylene carbonate, and a low viscosity solvent which is selected from the group consisting of dimethyl carbonate, methyl ethyl carbonate, diethyl carbonate, tetrahydrofuran, 2-methyltetrahydrofuran, 1,4-diode, 1,2-dimethoxyethane, 1,2-diethoxyethane, 1,2-dibutoxyethane, γ

-butyrolactone, acetonitrile, methyl propionate, and dimethylformamide.

8. The non-aqueous electrolytic solution of claim 2, wherein the non-aqueous solvent comprises a high dielectric constant solvent which is selected from the group consisting of ethylene carbonate, propylene carbonate, and butylene carbonate, and a low viscosity solvent which is selected from the group consisting of dimethyl carbonate, methyl ethyl carbonate, diethyl carbonate, tetrahydrofuran, 2-methyltetrahydrofuran, 1,4-dioxane, 1,2-dimethoxyethane, 1,2-diethoxyethane, 1,2-dibutoxyethane, γ

-butyrolactone, acetonitrile, methyl propionate, and dimethylformamide.

9. A lithium secondary battery comprising a positive electrode, a negative electrode, and a non-aqueous electrolytic solution which comprises a non-aqueous solvent and an electrolyte which further contains 0.001 to 0.8 weight % of a biphenyl derivative having the following formula:

10. The lithium secondary battery of claim 9, wherein the biphenyl derivative in the non-aqueous electrolytic solution has the following formula: