Method and apparatus for charging electric double layer capacitor

• US 5,498,951 A
• Filed: 06/30/1994
• Issued: 03/12/1996
• Est. Priority Date: 06/30/1993
• Status: Expired due to Term

• Current Assignee: Power Systems Incorporated (MinebeaMitsumi Inc.), Nantong Jianghai Capacitor Company Limited
• Original Assignee: JEOL Limited
• Inventors: Morimoto, Takeshi, Hiratsuka, Kazuya, Okamura, Michio
• Primary Examiner(s): Dougherty, Thomas M.
• Assistant Examiner(s): Ponomarenko, Nicholas
• Application Number:
  US08/269,010
• Time in Patent Office: 621 Days
• Field of Search: 320/1, 322/2 A, 322/2 R
• US Class Current: 322/2.00R
• CPC Class Codes: H02J 7/345 using capacitors as storage or buffering devices
• CPC Class Codes: Y02B 40/00 Technologies aiming at improving the efficiency of home appliances, e.g. induction cooking or efficient technologies for refrigerators, freezers or dish washers
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/13 Energy storage using capacitors

Abstract

Method and apparatus for quickly and efficiently charging an electric double layer capacitor. The capacitor is charged by a constant-current power supply which is preferably a current controlled output type switching power supply. To cause the voltage across the terminals of the capacitor to reach its working voltage in a short time, the capacitor is overcharged for a short time. Where the capacitor is charged with a solar battery, a constant-current output type switching regulator is interposed between the solar battery and the capacitor.

Claims

1. A method of charging an electric double layer capacitor, comprising the step of:

charging said electric double layer capacitor from a constant-current power supply.

6. A method of charging an electric double layer capacitor as set forth in claim 1, wherein said electric double layer capacitor is overcharged so that it is charged up to a preset voltage exceeding a working voltage of said capacitor.

7. A method of charging an electric double layer capacitor as set forth in claim 6, wherein said capacitor is overcharged by a constant current supplied from said constant-current power supply.

8. A method of charging an electric double layer capacitor as set forth in claim 6, wherein said capacitor is overcharged by a power supply other than said constant-current power supply.

9. A method of charging an electric double layer capacitor as set forth in any one of claims 6 to 8, wherein said capacitor is overcharged by an amount of electricity substantially corresponding to an amount of electricity injected during relaxation charging of said electric double layer capacitor.

2. An apparatus for charging an electric double layer capacitor, comprising:

a current controlled output type switching DC power supply which charges said electric double layer capacitor.

3. An apparatus for charging an electric double layer capacitor, comprising:

an electric power storage device to store electric energy from an external power line; and

a DC/DC converter for converting output electric power from said electric power storage device into a substantially constant-current output, said storage device supplying said substantially constant-current output to said electric double layer capacitor which acts as a load.

4. An apparatus for charging an electric double layer capacitor as set forth in claim 3, wherein said electric power storage device is controlled by a timer or a remote control signal and acting to store electric power during a predetermined period of time.

5. An apparatus for charging an electric double layer capacitor as set forth in claim 3 or 4, wherein said DC/DC converter is a switching constant-current converter.

10. A method of charging an electric double layer capacitor with a solar battery, comprising the steps of:

preparing said solar battery; and

placing a constant-current output switching regulator between said solar battery and said electric double layer capacitor to charge said capacitor with electric power from said solar battery.

11. A method of charging an electric double layer capacitor with a solar battery as set forth in claim 10, wherein constant output current from said switching regulator is so controlled as to approach a current value at which said solar battery produces its maximum output.