Cathode material for lithium secondary battery and method for producing lithiated nickel dioxide and lithium secondary battery

• US 5,677,086 A
• Filed: 07/01/1996
• Issued: 10/14/1997
• Est. Priority Date: 07/15/1993
• Status: Expired due to Term

• Current Assignee: Sumitomo Chemical Company Limited
• Original Assignee: Sumitomo Chemical Company Limited
• Inventors: Nakane, Kenji, Nishida, Yasunori, Satoh, Tomoari
• Primary Examiner(s): Willis, Jr., Prince
• Assistant Examiner(s): CHANEY, CAROL DIANE
• Application Number:
  US08/675,288
• Time in Patent Office: 470 Days
• Field of Search: 429/218, 429/223
• US Class Current: 429/223
• CPC Class Codes: C01G 53/42 containing alkali metals, e.g. LiNiO2
• CPC Class Codes: C01P 2002/30 Three-dimensional structures
• CPC Class Codes: C01P 2002/52 containing elements as dopants
• CPC Class Codes: C01P 2004/61 Micrometer sized, i.e. from 1-100 micrometer
• CPC Class Codes: C01P 2006/12 Surface area
• CPC Class Codes: C01P 2006/40 Electric properties
• CPC Class Codes: H01M 10/052 Li-accumulators
• 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: Y02E 60/10 Energy storage using batteries

Abstract

The invention provides a cathode material for lithium secondary battery containing lithiated nickel dioxide having excellent charge/discharge characteristics and a process for producing the lithiated nickel dioxide, and a lithium secondary battery. That is, the cathode material for lithium secondary battery contains lithiated nickel dioxide having α-NaFeO₂ structure and shows a coulomb efficiency of 85% or higher at the first charging and discharging, and the process for producing lithiated nickel dioxide comprises dispersing a nickel compound in a lithium nitrate solution, then evaporating the solvent to obtain a mixture of lithium nitrate and the nickel compound and firing the mixture in an atmosphere containing oxygen.

Claims

1. A cathode material for a lithium secondary battery comprising lithiated nickel dioxide having an α

-NaFeO₂ structure before a first charging/discharging cycle of the battery and maintaining the α

-NaFeO₂ structure after the first charging/discharging cycle, and the cathode material having a first charging/discharging coulomb efficiency of at least 85% contributed by the α

-NaFeO₂ structure.

2. A cathode material for a lithium secondary battery consisting essentially of lithiated nickel dioxide having an α

-NaFeO₂ structure, said α

-NaFeO₂ structure being maintained between a maximum voltage of 4.2V and a minimum voltage of 2.5V, the cathode material having a first charging and discharging coulomb efficiency of at least 85%.

3. A lithium secondary battery, comprising an anode of a material comprising lithium metal, a lithium alloy or a material in which lithium can be doped and undoped, a cathode comprising lithiated nickel dioxide having an α

-NaFeO₂ structure before a first charging/discharging cycle of the battery and maintaining the α

-NaFeO₂ structure after the first charging/discharging cycle in which lithium ion can be doped and from which lithium ion can be undoped, and a liquid or solid electrolyte, the cathode material having a first charging/discharging coulomb efficiency of at least 85% contributed by the α

-NaFeO₂ structure.

4. A lithium secondary battery, comprising an anode of a material comprising lithium metal, a lithium alloy or a material in which lithium can be doped and undoped, a cathode consisting essentially of lithiated nickel dioxide having an α

-NaFeO₂ structure in which lithium ion can be doped and from which lithium ion can be undoped, said α

-NaFeO₂ structure being maintained between a maximum voltage of 4.2V and a minimum voltage of 2.5V, and a liquid or solid electrolyte, the cathode material having a first charging and discharging coulomb efficiency of at least 85%.