Contactless rechargeable secondary battery and contactless battery charger

• US 9,438,066 B2
• Filed: 07/20/2012
• Issued: 09/06/2016
• Est. Priority Date: 08/09/2011
• Status: Active Grant

• Current Assignee: FDK Corporation (Fujitsu Limited)
• Original Assignee: FDK Corporation (Fujitsu Limited)
• Inventors: Toga, Yutaka, Tsuchiya, Katsuki, Suzuki, Tetsuya, Yoshihashi, Hidetaka, Teraoka, Hirohito
• Primary Examiner(s): Ngo, Brian
• Application Number:
  US14/236,060
• Publication Number:
  US 20140176067A1
• Time in Patent Office: 1,509 Days
• Field of Search: 320/106, 320/107, 320/108, 320/115, 320/154
• US Class Current: 1/1
• CPC Class Codes: H01F 27/2804 Printed windings
• CPC Class Codes: H01F 27/36 Electric or magnetic shields or screens movable for varying inductance H01F21/10
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H01M 10/46 Accumulators structurally combined with charging apparatus circuits for charging H02J7/00
• CPC Class Codes: H02J 50/005 Mechanical details of housing or structure aiming to accommodate the power transfer means, e.g. mechanical integration of coils, antennas or transducers into emitting or receiving devices
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/70 involving the reduction of electric, magnetic or electromagnetic leakage fields
• CPC Class Codes: H02J 7/0045 concerning the insertion or the connection of the batteries
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A contactless rechargeable alkaline secondary battery includes an alkaline secondary battery; a power receiver circuit having receiver coils and a resonance capacitor and adapted to receive AC power via magnetic field resonance, the resonance capacitor connected with the receiver coils L1 to L4; a rectifier circuit adapted to rectify the AC power; a current limiter circuit adapted to limit a charging current flowing from the rectifier circuit to the alkaline secondary battery; and an outer casing configured to be cylindrical in shape, adapted to house the alkaline secondary battery, and provided with a positive terminal and a negative terminal, the positive terminal being connected with a positive pole of the alkaline secondary battery and the negative terminal being connected with a negative pole of the alkaline secondary battery, wherein the power receiver coils are shaped like a sheet of an electric wire wound along a plane.

Claims

1. A contactless rechargeable secondary battery comprising:

a secondary battery;

a power receiver circuit provided with a power receiver coil and a resonance capacitor and adapted to receive AC power of resonance frequency via magnetic field resonance, the resonance capacitor being connected in parallel with the power receiver coil;

a rectifier circuit adapted to rectify the AC power received by the power receiver circuit;

a current limiter circuit adapted to limit a charging current flowing from the rectifier circuit to the secondary battery; and

an outer casing configured to be cylindrical in shape, adapted to house the secondary battery, and provided with a positive terminal and a negative terminal, the positive terminal being connected with a positive pole of the secondary battery and the negative terminal being connected with a negative pole of the secondary battery, wherein the power receiver coil is shaped like a sheet, that extends from the negative pole to the positive pole, by being made up of an electric wire wound along a plane and is installed along an inner surface of the outer casing.

2. The contactless rechargeable secondary battery according to claim 1, further comprising a magnetic layer installed between the secondary battery and the power receiver coil.

3. The contactless rechargeable secondary battery according to claim 1, further comprising an insulating layer installed between the secondary battery and the power receiver coil.

4. The contactless rechargeable secondary battery according to claim 1, further comprising an insulating layer installed between the power receiver coil and the inner surface of the outer casing.

11. The contactless rechargeable secondary battery according to claim 1, wherein a center of gravity is eccentric to an axis of the outer casing.

12. The contactless rechargeable secondary battery according to claim 1, wherein the rectifier circuit is a half-wave rectifier circuit.

13. The contactless rechargeable secondary battery according to claim 1, wherein the current limiter circuit includes a constant current circuit.

14. The contactless rechargeable secondary battery according to claim 1, wherein a quality factor of the resonance of the power receiver circuit is 100 or less.

15. The contactless rechargeable secondary battery according to claim 1, wherein the power receiver circuit has a plurality of the power receiver coils which are installed next to one another in a circumferential direction of the outer casing.

16. The contactless rechargeable secondary battery according to claim 15, wherein the power receiver circuit is configured such that the resonance capacitor is connected in parallel with the plurality of power receiver coils connected in series.

17. The contactless rechargeable secondary battery according to claim 15, wherein the power receiver circuit includes a plurality of resonance circuits in which the power receiver coil and the resonance capacitor are connected in parallel;

a plurality of the rectifier circuits are installed for the plurality of resonance circuits, respectively; and

outputs from the plurality of rectifier circuits are connected in parallel with one another.

18. The contactless rechargeable secondary battery according to claim 17, wherein the plurality of resonance circuits include a resonance circuit in which the power receiver coil is wound in a normal direction and a resonance circuit in which the power receiver coil is wound in a reverse direction.

19. The contactless rechargeable secondary battery according to claim 17, wherein the plurality of resonance circuits differ in resonance frequency from the resonance circuits adjacent to the power receiver coil.

20. The contactless rechargeable secondary battery according to claim 15, wherein the power receiver circuit includes a plurality of resonance circuits in which the power receiver coil and the resonance capacitor are connected in parallel;

and the plurality of resonance circuits include a first resonance circuit connected to the rectifier circuit and second resonance circuits connected to the rectifier circuit via other resonance circuits by magnetic coupling between the resonance circuits.

21. The contactless rechargeable secondary battery according to claim 20, wherein the resonance frequency of the second resonance circuits differs from the resonance frequency of the first resonance circuit within a range of a full width at half maximum of the resonance frequency of the first resonance circuit.

5. A contactless rechargeable secondary battery, comprising:

a secondary battery;

a power receiver circuit provided with a power receiver coil and a resonance capacitor and adapted to receive AC power of resonance frequency via magnetic field resonance, the resonance capacitor being connected in parallel with the power receiver coil;

a rectifier circuit adapted to rectify the AC power received by the power receiver circuit;

a current limiter circuit adapted to limit a charging current flowing from the rectifier circuit to the secondary battery; and

an outer casing configured to be cylindrical in shape, adapted to house the secondary battery, and provided with a positive terminal and a negative terminal, the positive terminal being connected with a positive pole of the secondary battery and the negative terminal being connected with a negative pole of the secondary battery, wherein the power receiver coil is shaped like a sheet by being made up of an electric wire wound along a plane and is installed along an outer surface, that extends from the negative pole to the positive pole, of the outer casing.

6. The contactless rechargeable secondary battery according to claim 5, further comprising a magnetic layer installed between the outer surface of the outer casing and the power receiver coil.

7. The contactless rechargeable secondary battery according to claim 5, further comprising an insulating layer installed between the outer surface of the outer casing and the power receiver coil.

8. The contactless rechargeable secondary battery according to claim 5, further comprising an insulating layer adapted to cover an outer side of the power receiver coil.

9. A contactless rechargeable secondary battery, comprising:

a secondary battery cylindrical in shape;

an insulating layer adapted to cover an outer surface of the secondary battery;

a power receiver circuit provided with a power receiver coil and a resonance capacitor and adapted to receive AC power of resonance frequency via magnetic field resonance, the power receiver coil being shaped like a sheet by being made up of an electric wire wound along a plane, that extends from a negative pole to a positive pole, and the resonance capacitor being connected in parallel with the power receiver coil;

a rectifier circuit adapted to rectify the AC power received by the power receiver circuit; and

a current limiter circuit adapted to limit a charging current flowing from the rectifier circuit to the secondary battery, wherein the power receiver circuit, the rectifier circuit, and the current limiter circuit are installed between the outer surface of the secondary battery and the insulating layer.

10. The contactless rechargeable secondary battery according to claim 9, further comprising a magnetic layer installed between the outer surface of the secondary battery and the power receiver coil.

22. A contactless battery charger, comprising:

a power supply circuit adapted to output AC power of resonance frequency;

a power transmission circuit provided with a power transmission coil and a resonance capacitor and adapted to transmit the AC power of the resonance frequency via magnetic field resonance, the resonance capacitor being connected in parallel with the power transmission coil;

a shielding structure adapted to provide a shield to prevent external leakage of electromagnetic waves emitted from the power transmission circuit;

a switch adapted to open and close a route of AC power supply from the power supply circuit to the power transmission circuit by engaging with the shielding structure such that the AC power is supplied from the power supply circuit to the power transmission circuit with a shield against the electromagnetic waves from the power transmission circuit being provided by the shielding structure; and

a placement surface on which a contactless rechargeable secondary battery is placed in order for the power transmission coil to emit electromagnetic waves, wherein the power transmission coil is installed parallel to the placement surface, and is shaped like a sheet by being made up of an electric wire wound along a plane.

23. The contactless battery charger according to claim 22, further comprising a magnetic layer installed between the power transmission coil and the power supply circuit.

24. The contactless battery charger according to claim 22, further comprising a control device adapted to control the power supply circuit such that electric power is transmitted intermittently from the power transmission circuit.

25. The contactless battery charger according to claim 22, wherein the shielding structure includes a shielding cover openably and closably supported and adapted to cover the placement surface when closed;

and the switch opens with the shielding cover closed and with surroundings of the placement surface being shielded.

26. The contactless battery charger according to claim 22, wherein the shielding structure includes an insertable/withdrawable tray whose inside bottom surface serves as the placement surface;

and the switch opens with the tray being inserted into a predetermined position, shielding surroundings of the inside bottom surface of the tray.