ENERGY CONVERSION DEVICE

• US 20080206638A1
• Filed: 01/30/2008
• Published: 08/28/2008
• Est. Priority Date: 02/26/2007
• Status: Active Grant

• Current Assignee: Shin-Kobe Electric Machinery Company Limited (Resonac Holdings Corp.)
• Original Assignee: Shin-Kobe Electric Machinery Company Limited (Resonac Holdings Corp.)
• Inventors: Takahashi, Hirofumi, Sakai, Masanori, Honbo, Kyoko
• Granted Patent: US 7,742,279 B2
• Time in Patent Office: Days
• US Class Current: 429/209
• CPC Class Codes: H01G 11/04 Hybrid capacitors
• CPC Class Codes: H01G 11/08 Structural combinations, e.g. assembly or connection, of hybrid or EDL capacitors with other electric components, at least one hybrid or EDL capacitor being the main component
• CPC Class Codes: H01G 11/22 Electrodes
• CPC Class Codes: H01G 11/28 arranged or disposed on a current collector; Layers or phases between electrodes and current collectors, e.g. adhesives
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/06 Lead-acid accumulators semi-lead accumulators H01M10/20
• CPC Class Codes: H01M 10/345 Gastight metal hydride accumulators
• CPC Class Codes: H01M 4/13 Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
• CPC Class Codes: H01M 4/14 Electrodes for lead-acid accumulators
• CPC Class Codes: H01M 4/242 Hydrogen storage electrodes
• CPC Class Codes: H01M 4/32 Nickel oxide or hydroxide electrodes
• CPC Class Codes: H01M 4/366 as layered products
• CPC Class Codes: H01M 4/62 Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A secondary battery comprises a single-plate lead acid battery (Va), a positive electrode capacitor layer and a negative electrode capacitor layer, which are formed on the respective surfaces of a positive electrode plate, and a negative electrode plate. Each of the positive electrode plate and negative electrode plate contains an active material, to have a configuration in which activated carbon has a concentration gradient. The electronic resistance between a collector terminal and the center of a portion where activated carbon is present at a high concentration is lower than the electronic resistance between the collector terminal and the center of a portion where activated carbon is present at a low concentration. In the single-plate lead acid battery, charges are accumulated in the positive electrode capacitor layer and in the negative electrode capacitor layer.

Claims

1. An energy conversion device comprising:

at least a pair of electrodes at least one of which contains a capacitor material; and

an electrolyte having ion conductivity and electron insulation, the energy conversion device using an electric double layer formed at an interface between the capacitor material and the electrolyte to store energy, wherein

a layer of the capacitor material is formed to be closer to a collector terminal than an active material layer of each of the electrodes such that an electronic resistance A between the collector terminal and a center of gravity of the capacitor material layer in the electrode is lower than an electronic resistance B between the collector terminal and a center of gravity of a surface of the active material layer of the electrode.

6. The energy conversion device of claim 1, wherein the pair of electrodes are composed of a positive electrode containing lead dioxide as a main active material and a negative electrode containing metallic lead as a main active material.

7. The energy conversion device of claim 1, wherein the pair of electrodes are composed of a positive electrode and a negative electrode each capable of occlusion and desorption of a lithium ion, and the electrolyte contains a lithium salt or a lithium compound.

8. The energy conversion device of claim 1, wherein the pair of electrodes is composed of a positive electrode containing nickel hydroxide as a main active material and a negative electrode containing a hydrogen-occulated alloy as a main active material, and the electrolyte contains a hydroxide ion.

9. The energy conversion device of claim 1, wherein the capacitor material is activated carbon.

2. An energy conversion device comprising:

at least a pair of electrodes at least one of which contains a capacitor material; and

an electrolyte having ion conductivity and electron insulation, the energy conversion device using an electric double layer formed at an interface between the capacitor material and the electrolyte to store energy, wherein

a layer of the capacitor material is formed on the electrode such that an electronic resistance A between a collector terminal and a center of gravity of a portion of the electrode on which the capacitor material layer is formed is lower than an electronic resistance B between the collector terminal and a center of gravity of an active material layer of each of the electrodes.

3. An energy conversion device comprising:

at least a pair of electrodes at least one of which contains a capacitor material; and

an electrolyte having ion conductivity and electron insulation, the energy conversion device using an electric double layer formed at an interface between the capacitor material and the electrolyte to store energy, wherein

a portion A and a portion B are formed in the electrode such that an electronic resistance between a collector terminal, and a center of gravity of the corresponding one of the portions is lower in the portion A than in the portion B and the capacitor material is disposed to have a concentration per unit area or per unit volume which is higher in the portion A than in the portion B (where the concentration of the capacitor material in the portion B includes zero).

4. The energy conversion device of claim 3, wherein a distance between the collector terminal and the portion A in which the capacitor material is disposed to have a higher concentration is shorter than a distance between the collector terminal and the portion B in which the capacitor material is disposed to have a lower concentration.

5. The energy conversion device of claim 3, wherein the portion A is disposed within the electrode and the portion B is disposed in the vicinity of a surface of the electrode.