Spiral-wound galvanic cell

• US 5,021,306 A
• Filed: 11/15/1989
• Issued: 06/04/1991
• Est. Priority Date: 01/30/1989
• Status: Expired due to Fees

• Current Assignee: Varta Batterie AG (Michael Tojner, PhD, LLD)
• Original Assignee: Varta Batterie AG (Michael Tojner, PhD, LLD)
• Inventors: Kramer, Peter, Sauer, Hans
• Primary Examiner(s): Skapars, Anthony
• Application Number:
  US07/436,650
• Time in Patent Office: 566 Days
• Field of Search: 429/94, 429/178, 429/121
• US Class Current: 429/94
• CPC Class Codes: H01M 50/50 Current conducting connections for cells or batteries
• CPC Class Codes: H01M 6/10 with wound or folded electrodes

Abstract

A spiral-wound galvanic cell is based upon a lithium system with a nonaqueous electrolyte, and includes a positive electrode, the carrier of which is clamped within the slit of a simple metal splint which serves as the winding mandrel and current collector. Contact with the metal splint is established by a leaf spring associated with the housing cover, which then serves as the positive terminal post for the cell. A high specific contact pressure is developed at this connection by providing the leaf spring with a punched hole which rests on thicker top portions of the metal splint. A small metal plate pressed through the lithium electrode and its separator establishes electrical contact between the lithium electrode and the interior wall of the housing vessel, which then serves as the negative cell pole.

Claims

1. A galvanic cell comprising a spiral-shaped electrode body which is formed from windings of band-shaped positive and negative electrodes with the imposition of a band-shaped separator, a current collector which serves as a winding mandrel and which is electrically connected with a first of said electrodes, wherein said current collector is a metal needle having a slit clamped to carrier portions of said first electrode, a metal housing for receiving the spiral-shaped electrode body and which is electrically connected with a second one of said electrodes, a cover which seals the opening of the housing and which serves as a terminal post for the electrode which is electrically connected to the current collector, and a contact for bridging the cover and the current collector, wherein said contact takes the form of a leaf spring attached to interior portions of the cover and which rests upon the current collector under elastic tension.

2. The galvanic cell of claim 1 wherein the current collector is a metal splint having a closed top end which is shaped into an eye.

3. The galvanic cell of claim 2 wherein the leaf spring includes an aperture having a diameter which is smaller than the eye of the metal splint, so that the aperture of the leaf spring rests against the eye of the metal splint under high specific contact pressure.

4. The galvanic cell of claim 1 wherein the leaf spring includes means for positioning the current collector within said galvanic cell.

5. The galvanic cell of claim 4 wherein said positioning means is an aperture formed in the leaf spring for engaging end portions of the current collector.

6. A galvanic cell comprising a spiral-shaped electrode body which is formed from windings of band-shaped positive and negative electrodes with the imposition of a bandshaped separator, a current collector which serves as a winding mandrel and which is electrically connected with a first of said electrodes, wherein said current collector is a metal needle having a slit clamped to carrier portions of said first electrode, a metal housing for receiving the spiral-shaped electrode body and which is electrically connected with a second one of said electrodes, a cover which seals the opening of the housing and which serves as a terminal post for the electrode which is electrically connected to the current collector, and a flexible contact for bridging the cover and the current collector having means for positioning the current collector within the galvanic cell, wherein said contact takes the form of a leaf spring attached to interior portions of the cover and which rests upon the current collector under elastic tension.

7. The galvanic cell of claim 6 wherein the current collector is a metal splint having a closed top end which is shaped into an eye.

8. The galvanic cell of claim 7 wherein the positioning means is an aperture formed in the leaf spring and having a diameter which is smaller than the eye of the metal splint, so that the aperture of the leaf spring rests against the eye of the metal splint under high specific contact pressure.