Non-contact battery charging equipment using a soft magnetic plate

• US 6,008,622 A
• Filed: 09/28/1998
• Issued: 12/28/1999
• Est. Priority Date: 09/29/1997
• Status: Expired due to Term

• Current Assignee: NEC Energy Devices, Ltd. (Envision Group /TX/)
• Original Assignee: NEC Mobile Energy Corporation (NEC Corporation)
• Inventors: Nakawatase, Norio
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): TOATLEY, GREGORY J
• Application Number:
  US09/161,439
• Time in Patent Office: 456 Days
• Field of Search: 320/108
• US Class Current: 320/108
• 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: 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

Abstract

The invention provides a non-contact charging equipment having high transmission efficiency and used to supply electric power on non-contact basis by electromagnetic induction, whereby it comprises a plurality of coils on a planar magnetically soft material on each of power transmitting and power receiving sides, whereby the coils on the power transmitting side and the power receiving side are arranged at opposed positions and with a spacing so that magnetic fluxes generated by adjacent coils are directed in reverse directions, the magnetically soft material in planar shape on the power receiving side is arranged directly or via an insulating member on a battery can, and heat generated on the power receiving side is radiated by the battery can.

Claims

1. A non-contact charging equipment for supplying electric power on non-contact basis by electromagnetic induction, comprising a plurality of coils on a planar magnetically soft material on each of power transmitting and power receiving sides, whereby the coils on the power transmitting side and the power receiving side are arranged at opposed positions and with a spacing so that magnetic fluxes generated by adjacent coils are directed in reverse directions, the magnetically soft material in planar shape on the power receiving side is arranged directly or via an insulating member on a battery can, and heat generated on the power receiving side is radiated by the battery can.

2. A non-contact charging equipment according to claim 1, wherein said equipment is arranged in a battery pack.

3. A non-contact charging equipment according to claim 1, wherein said magnetically soft material is a magnetically soft ferrite plate.

4. A non-contact charging equipment according to claim 2, wherein said magnetically soft material is a magnetically soft ferrite plate.

5. A non-contact charging equipment according to claim 3, wherein thickness of the magnetically soft ferrite plate on the power receiving side is 0.1 to 5.0 mm.

6. A non-contact charging equipment according to claim 4, wherein thickness of the magnetically soft ferrite plate on the power receiving side is 0.1 to 5.0 mm.

7. A non-contact charging equipment according to claim 1, wherein the battery to be charged is a lithium ion battery.