Carbonaceous electrode material for secondary battery

• US 6,569,570 B2
• Filed: 10/18/1999
• Issued: 05/27/2003
• Est. Priority Date: 02/06/1997
• Status: Expired due to Term

• Current Assignee: Kureha Corporation
• Original Assignee: Kureha Kagaku Kogyo Kabushiki Kaisha
• Inventors: Sonobe, Naohiro, Masuko, Jiro, Ishikawa, Minoru
• Primary Examiner(s): Gulakowski, Randy
• Assistant Examiner(s): WILLS, MONIQUE M
• Application Number:
  US09/355,481
• Publication Number:
  US 20020039686A1
• Time in Patent Office: 1,317 Days
• Field of Search: 429/231.8, 429/218.1, 423/593, 423/414, 252/502
• US Class Current: 429/231.8
• CPC Class Codes: C01B 32/05 Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30
• CPC Class Codes: C04B 2235/422 Carbon
• CPC Class Codes: C04B 2235/48 Organic compounds becoming part of a ceramic after heat treatment, e.g. carbonising phenol resins
• CPC Class Codes: C04B 2235/5436 micrometer sized, i.e. from 1 to 100 micron
• CPC Class Codes: C04B 35/524 obtained from polymer precursors, e.g. glass-like carbon material
• CPC Class Codes: C04B 35/528 obtained from carbonaceous particles with or without other non-organic components
• CPC Class Codes: C04B 35/6267 Pyrolysis, carbonisation or auto-combustion reactions
• CPC Class Codes: C04B 35/6268 characterised by the applied pressure or type of atmosphere, e.g. in vacuum, hydrogen or a specific oxygen pressure
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 2004/021 Physical characteristics, e.g. porosity, surface area
• CPC Class Codes: H01M 4/133 Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
• CPC Class Codes: H01M 4/587 for inserting or intercalating light metals
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A carbonaceous electrode having improved capacities for doping and dedoping of a cell active substance, such as lithium, and suitable for a non-aqueous secondary battery, is constituted by a carbonaceous material obtained by carbonizing an aromatic condensation polymer formed by condensation of an aromatic compound having a phenolic hydroxy group and an aldehyde. The carbonaceous material is characterized by an atomic ratio H/C between hydrogen atoms and carbon atoms of below 0.1, a carbon dioxide adsorption capacity of at least 10 ml/g, and an X-ray scattering intensity ratio I_W/I_D of at least 0.25, wherein I_W and I_D represent scattering intensities as measured in a wet state and a dry state, respectively, at a parameter s=2·sin θ/λ of 0.5 nm⁻¹, wherein θ denotes a scattering angle and λ denotes a wavelength of X-rays in X-ray small-angle scattering measurement.

Claims

1. A carbonaceous electrode material for a secondary battery, comprising:

a carbonization product of an aromatic condensation polymer formed by condensation of an aromatic compound having a phenolic hydroxy group and an aldehyde; and

having an atomic ratio H/C between hydrogen atoms and carbon atoms of below 0.1, an average (002)-plane spacing of 0.365-0.395 nm as measured by X-ray diffraction method, a carbon dioxide adsorption capacity of at least 10 ml/g, and an X-ray scattering intensity ratio I_W/I_D of at least 0.25, wherein I_W and I_D represent scattering intensities as measured in a wet state and a dry state, respectively, at a parameter s=2·

sin θ

/λ

, of 0.5 nm<sup>−

1</sup>, wherein θ

denotes a scattering angle and λ

denotes a wavelength of X-rays in 2·

sin θ

/λ

of 0.5 nm<sup>−

1</sup>, wherein θ

denotes a scattering angle and λ

denotes a wavelength of X-rays in X-ray small-angle scattering measurement, and

wherein the carbonaceous electrode material is particulate in form having an average particle diameter of at most 100 μ

m.

2. A carbonaceous electrode material according to claim 1, wherein said aromatic condensation polymer is a resol phenolic resin formed by condensation of phenol and an aldehyde.

3. A process for producing the carbonaceous electrode material for a non-aqueous solvent secondary battery according to claim 1, comprising:

forming a resol phenolic resin by condensation of an aromatic compound having a phenolic hydroxyl group and an aldehyde in a mol ratio 1 to 1-3 in the presence of a basic catalyst selected from the group consisting of sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium carbonate, potassium carbonate, lithium carbonate and ammonia, pre-calcining and pulverizing the resol phenolic resin to an average particle diameter of at most 100 μ

m, and carbonizing the pulverized resol phenolic resin at a temperature of 1050-1400°

C. under a pressure exceeding 10 kPa in contact with a flowing inert gas.

4. A process for producing a carbonaceous electrode material for a non-aqueous solvent secondary battery as recited in claim 1, comprising:

forming a resol phenolic resin by condensation of an aromatic compound having a phenolic hydroxyl group and an aldehyde in a mol ratio of 1 to 1-3 in the presence of a basic catalyst selected from the group consisting of sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium carbonate, potassium carbonate, lithium carbonate and ammonia, pre-calcining and pulverizing the resol phenolic resin to an average particle diameter of at most 100 μ

m, and carbonizing the pulverized resol phenolic resin at a temperature of 1050-1400°

C. under a pressure of at most 10 kPa.

5. An electrode structure for a non-aqueous solvent secondary battery, comprising:

an electroconductive substrate and a composite electrode layer disposed on at least one surface of the electroconductive substrate;

said composite electrode layer comprising a carbonaceous electrode material according to claim 1 in a particulate form, and a binder.

6. A non-aqueous solvent secondary battery, comprising:

a positive electrode, a negative electrode, and a separator and a non-aqueous electrolytic solution disposed between the positive and negative electrodes;

at least one of said positive and negative electrodes comprising an electrode structure according to claim 5.

7. A secondary battery according to claim 6, wherein the electrode structure constitutes the negative electrode.