Battery pack rechargeable by magnetic induction effect

• US 20080061735A1
• Filed: 09/05/2007
• Published: 03/13/2008
• Est. Priority Date: 09/07/2006
• Status: Active Grant

• Current Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Matsuda, Takuya, Inoue, Yasushi, Toya, Shoichi
• Granted Patent: US 8,115,447 B2
• Time in Patent Office: Days
• US Class Current: 320/108
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H02J 50/10 using inductive coupling
• 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 battery pack rechargeable by a magnetic induction effect incorporates a secondary coil electromagnetically coupled to a primary coil of a battery charger and a secondary battery rechargeable by electric power induced to the secondary coil. The secondary battery is in a form of a thin battery having a larger width than a thickness, and two opposing surfaces of the secondary battery are composed of a first flat surface and a second flat surface. The secondary coil is in a form of a planar coil with a wire material being spirally coiled in the plane. In the battery pack, the secondary coil in the form of the planar coil is fixedly layered on the first flat surface of the thin battery.

Claims

1. A battery pack rechargeable by a magnetic induction effect, the battery pack comprising:

a secondary coil electromagnetically coupled to a primary coil incorporated in a battery charger; and

a secondary battery rechargeable by electric power induced to the secondary coil,

wherein the secondary battery is in a form of a thin battery having a larger width than a thickness, and two opposing surfaces composed of a first flat surface and a second flat surface,

wherein the secondary coil is in a form of a planar coil with a wire material being spirally coiled in the plane, and

wherein the secondary coil in the form of the planar coil is fixedly layered on the first flat surface of the thin battery.

2. The battery pack rechargeable by a magnetic induction effect as recited in claim 1, wherein the wire material for the secondary coil is in a spirally coiled form of a planar coil with a plurality of insulated metallic wires being placed in parallel with respect to the first flat surface, a surface of each wire being insulated with an insulating coating, and wherein the parallel plurality of metallic wires spirally coiled are disposed in an electrically parallel connection.

3. The battery pack rechargeable by a magnetic induction effect as recited in claim 1, wherein the wire material for the secondary coil is the insulated metallic wire, a surface of which is insulated with the insulation coating, wherein the insulated metallic wire, in its cross section, has a larger width being parallel with respect to the first flat surface of the thin battery than a thickness being orthogonal to the first flat surface.

4. The battery pack rechargeable by a magnetic induction effect as recited in claim 1, wherein the insulated metallic wire for the secondary coil is rectangular in a cross section of the wire.

5. The battery pack rechargeable by a magnetic induction effect as recited in claim 1, wherein the secondary coil is in a form of planar coil with the wire material being spirally coiled on a planar surface, and is integrated by using an adhesive material or a painting material.

6. The battery pack rechargeable by a magnetic induction effect as recited in claim 1, wherein the secondary coil is in a plurality of tiers of flatly coiled wire materials.

7. The battery pack rechargeable by a magnetic induction effect as recited in claim 1, wherein the secondary coil is fixedly layered via the electromagnetic shield coating to the first flat surface of the thin battery.

8. The battery pack rechargeable by a magnetic induction effect as recited in claim 7, wherein the electromagnetic shield coating is fixed to the first flat surface of the thin battery by means of an adhesive layer.

9. The battery pack rechargeable by a magnetic induction effect as recited in claim 7, wherein the electromagnetic shield coating is in a sheet form of amorphous metal.

10. The battery pack rechargeable by a magnetic induction effect as recited in claim 1, further comprising a rectangular frame casing for covering a periphery of the flat surface of the thin battery, a circuit board disposed between the frame casing and the thin battery, a circuit board holder for placing the circuit board in position, and a spacer for covering the first flat surface of the thin battery.

11. The battery pack rechargeable by a magnetic induction effect as recited in claim 10, wherein the frame casing is disposed outside the thin battery, the circuit board is placed in position between the frame casing and the thin battery by means of the circuit board holder, and the spacer is layered on the first flat surface of the thin battery, with the secondary coil in the form of the planar coil being disposed on the spacer, so that an exterior side surface of the secondary coil may be made flush or coplanar with a peripheral surface of the spacer, and thus the exterior side surface of the battery assembly being covered by a plastic film.

12. The battery pack rechargeable by a magnetic induction effect as recited in claim 10, wherein the spacer has a fitting-in recess for fitting the secondary coil therein, the fitting-in recess being provided with a lower step portion for disposing a central outgoing wire to be drawn out of a center portion of the secondary coil.

13. The battery pack rechargeable by a magnetic induction effect as recited in claim 10, wherein the circuit board holder is provided with the integrally formed spacer for covering the first flat surface of the thin battery.

14. The battery pack rechargeable by a magnetic induction effect as recited in claim 10, wherein the spacer is provided with a fitting-in recess on a surface of the spacer, for fitting the secondary coil thereon.

15. The battery pack rechargeable by a magnetic induction effect as recited in claim 10, wherein the spacer is provided with a fitting-in hole, extended through both faces of the spacer, for fitting the secondary coil therein.

16. The battery pack rechargeable by a magnetic induction effect as recited in claim 1, wherein the thin battery is a lithium-ion battery.

17. The battery pack rechargeable by a magnetic induction effect as recited in claim 1, wherein the thin battery is a lithium polymer battery.