Lithium secondary battery

• US 5,804,335 A
• Filed: 05/27/1997
• Issued: 09/08/1998
• Est. Priority Date: 11/28/1994
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Cable Industries Limited (Mitsubishi Materials Corporation)
• Original Assignee: Mitsubishi Cable Industries Limited (Mitsubishi Materials Corporation)
• Inventors: Takada, Yoshinori, Kamauchi, Masahiro
• Primary Examiner(s): Gorgos, Kathryn L.
• Assistant Examiner(s): CHANEY, CAROL DIANE
• Application Number:
  US08/849,192
• Time in Patent Office: 469 Days
• Field of Search: 429/218, 429/219
• US Class Current: 429/231.95
• 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 4/38 of elements or alloys
• CPC Class Codes: H01M 4/40 Alloys based on alkali metals
• CPC Class Codes: H01M 4/405 Alloys based on lithium
• CPC Class Codes: H01M 4/485 of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy H01M4/505, H01M4/525 take precedence
• CPC Class Codes: H01M 4/525 of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
• CPC Class Codes: H01M 4/5825 Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
• CPC Class Codes: H01M 6/10 with wound or folded electrodes
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A lithium secondary battery comprising a positive electrode composed of a positive electrode active material comprising an oxide compound comprising at least Li and Ni, and a negative electrode comprising an Li--Ag--Te alloy, a positive electrode active material for a lithium secondary battery, which is composed of an oxide compound represented by the formula: LiNi_w Al_x P_y O_z wherein 0.80<w<1.10, 0<x<0.015, 0<y<0.03 and 1.8≦z≦2.2, and a lithium secondary battery comprising said positive electrode active material. The lithium secondary battery of the present invention shows large charge-discharge capacity, high energy density, less degradation by the repetitive charge-discharge and is superior in cycle property. The positive electrode active material of the present invention, which is composed of an oxide compound represented by the formula: LiNi_w Al_x P_y O_z is economical and superior in the supply of starting materials, and the lithium secondary battery comprising said positive electrode active material is advantageous in that it has high capacity, is superior in cycle property and can be prepared stably at low costs.

Claims

1. A lithium secondary battery comprising a positive electrode composed of a positive electrode active material comprising an oxide compound comprising at least Li and Ni, and a negative electrode comprising an Li--Ag--Te alloy.

2. The lithium secondary battery of claim 1, wherein the positive electrode active material is composed of an oxide compound of, besides Li and Ni, at least one member selected from the group consisting of Co, Fe, Cr, V, Mn, P, Al, In, Sn, Ti, Cu, Ga, Ag and Zn.

3. The lithium secondary battery of claim 1, wherein the atomic ratio of Li--Ag--Te alloy is Li:

Ag;

Te=10-120;

1-20;

0.001-2.

4. The lithium secondary battery of claim 1, wherein the negative electrode is composed of an Li--Ag--M1--M2--Te alloy wherein M1 is at least one member selected from 3A, 4A and 5A group metals in the periodic table, and M2 is at least one member selected from transition metals except Ag.

5. The lithium secondary battery of claim, 4, wherein the atomic ratio of the Li--Ag--M1--M2--Te alloy is Li:

Ag;

M1;

M2;

Te =10-120;

1-30;

1-100;

1-30;

0.001-2.