SECONDARY BATTERY AND CARBON INK FOR CONDUCTIVE AUXILIARY LAYER OF THE SAME

• US 20110129730A1
• Filed: 07/03/2009
• Published: 06/02/2011
• Est. Priority Date: 07/03/2008
• Status: Abandoned Application

• Current Assignee: DIC Corporation, NEC Corporation
• Original Assignee: DIC Corporation, NEC Corporation
• Inventors: Suguro, Masahiro, Obata, Takayoshi, Kasai, Masanori, Nakahara, Kentaro, Iwasa, Shigeyuki, Isozumi, Hiroshi
• Application Number:
  US13/001,736
• Publication Number:
  US 20110129730A1
• Time in Patent Office: Days
• US Class Current: 429/213
• CPC Class Codes: H01M 4/136 Electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy
• CPC Class Codes: H01M 4/60 of organic compounds
• CPC Class Codes: H01M 4/606 containing aromatic main chain polymers
• CPC Class Codes: H01M 4/625 Carbon or graphite
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A secondary battery using a polymer radical material and a conducting additive in which the performance of a conductive auxiliary layer is further improved and the internal resistance is reduced, thereby achieving a higher output. Specifically disclosed is a secondary battery in which at least one of a positive electrode and a negative electrode uses, as an electrode active material, a polymer radical material and a conducting additive having electrical conductivity. By providing a conductive auxiliary layer between a current collector and the polymer radical material/conducting additive electrode which is mainly composed of graphite, fibrous carbon or a granular carbon having a DBP absorption of not more than 110 cm³/100 g, the secondary battery with a higher output can be obtained.

Claims

1. A secondary battery in which at least one of a positive electrode and a negative electrode uses, as an electrode active material, a polymer radical material and a 5 conducting additive exhibiting electrical conductivity,

the secondary battery comprising a conductive auxiliary layer provided between a current collector and the polymer radical material/conducting additive electrode which is mainly composed of any one of graphite, fibrous carbon or a granular carbon having a DBP absorption of not more than 110 cm³/100 g.

2. The secondary battery according to claim 1, wherein, the conductive auxiliary layer is mainly composed of a granular carbon having a DBP absorption of not less than 30 cm³/100 g and not more than 110 cm³/100 g.

3. The secondary battery according to claim 1, wherein the mass ratio of graphite, fibrous carbon or a granular carbon having a DBP absorption of not more than 110 cm³/100 g of the conductive auxiliary layer is not less than 50% and not more than 95%.

4. The secondary battery according to claim 1, wherein the film thickness of the conductive auxiliary layer after drying is not more than 6 μ

m.

5. The secondary battery according to claim 1, wherein the polymer radical material is a polynitroxyl radical compound having a nitroxyl radical structure represented by a general formula (1) within a repeating unit:

6. The secondary battery according to claim 5, wherein the polynitroxyl radical compound is poly(4-methacryloyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl), poly(4-acryloyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl), or a copolymer containing these as the components thereof.

7. The secondary battery according to claim 5, wherein the polynitroxyl radical compound is poly(4-vinyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl) or a copolymer containing this as the component thereof.

8. The secondary battery according to claim 5, wherein the polynitroxyl radical compound has a cross-linked structure.

9. The secondary battery according to claim 1, wherein the secondary battery is a lithium secondary battery.

10. A carbon ink for a conductive auxiliary layer of a secondary battery in which at least one of a positive electrode and a negative electrode uses, as an electrode active material, a polymer radical material and a conducting additive exhibiting electrical conductivity,

the carbon ink for the conductive auxiliary layer to be used for forming the conductive auxiliary layer provided between a current collector and the polymer radical material/conducting additive electrode,

the carbon ink comprising any one of graphite, fibrous carbon or a granular carbon having a DBP absorption of not more than 110 cm³/100 g.