US 6,190,426 B1Granted

Methods of preparing prismatic cells

AssigneeMoltech Corporation

InventorsWilliam C. Thibault, Eric V. Kanto, Yordan M. Gernov, Christopher S. Dodds, Terje A. Skotheim

Life of this patent

Estimating the term…

Loading patent…

Abstract

The present invention pertains to methods of preparing prismatic cells which comprise the steps of winding lithium metal anode, separator, and cathode layers on a rounded mandrel having a large circumference relative to the external dimensions of the prismatic cell stack and of compressing the multilayer rounded cell stack into a prismatic shape and then filling the prismatic subassembly with electrolyte to form a prismatic ell stack, or alternatively of winding into such a rounded cell stack and filling with electrolyte and then compressing into a prismatic cell stack, prior to enclosing the prismatic cell stack in a barrier material film and sealing to form the casing of the prismatic cell. The present invention also pertains to electric current producing cells prepared according to such methods.

Claims103

Dependent claims

A method of preparing a multilayer electric current producing cell, said cell comprising a casing and a prismatic cell stack, said prismatic cell stack having an external length dimension, an external width dimension, an external thickness dimension, two substantially parallel flat surfaces, and outside permeable surfaces;

which method comprises, in order, the steps of:
(a) providing a laminar combination of:
(i) an anode comprising an anode active layer, which layer comprises an anode active material comprising lithium;
(ii) a solid composite cathode comprising a cathode active layer, which layer comprises a cathode active material, said cathode active layer having a first surface and a second opposite surface, said solid composite cathode further comprising a non-permeable current collector in contact with said first surface of said cathode active layer;
and,
(iii) a separator interposed between said anode and said solid composite cathode, and in contact with said second surface of said cathode active layer;
wherein said anode active layer and said cathode active layer are positioned in a face-to-face relationship;
(b) winding said combination on a mandrel having a cross-section of a rounded shape and having a circumference selected from the lengths consisting of:
(i) 140 to 200 per cent of the difference between said external length dimension and said external thickness dimension of said prismatic cell stack;
and,
(ii) 140 to 200 per cent of the difference between said external width dimension and said external thickness dimension of said prismatic cell stack;
said winding forming a rounded anode-separator-solid composite cathode subassembly having a jellyroll configuration and a rounded shape;
(c) removing said mandrel from said rounded subassembly;
(d) compressing said rounded subassembly in a press to form a prismatic subassembly having two substantially parallel flat surfaces;
(e) removing said prismatic subassembly from said press;
(f) contacting said prismatic subassembly with a source of a liquid nonaqueous lithium salt electrolyte to form said prismatic cell stack, wherein said electrolyte substantially fills porous areas within said prismatic cell stack;
(g) removing said prismatic cell stack from contact with said source of electrolyte;
(h) enclosing said prismatic cell stack in a barrier material film;
and,
(i) sealing said film to form said casing.

17 more elements

which method comprises, in order, the steps of:
(a) providing a laminar combination of:
(i) an anode comprising an anode active layer, which layer comprises an anode active material comprising lithium;
(ii) a solid composite cathode comprising a cathode active layer, which layer comprises a cathode active material, said cathode active layer having a first surface and a second opposite surface, said solid composite cathode further comprising a non-permeable current collector in contact with said first surface of said cathode active layer;
and,
(iii) a separator interposed between said anode and said solid composite cathode, and in contact with said second surface of said cathode active layer,
wherein said anode active layer and said cathode active layer are positioned in a face-to-face relationship;
(b) winding said combination on a mandrel having a cross-section of a rounded shape and having a circumference selected from the lengths consisting of:
(i) 140 to 200 per cent of the difference between said external length dimension and said external thickness dimension of said prismatic cell stack;
and,
(ii) 140 to 200 per cent of the difference between said external width dimension and said external thickness dimension of said prismatic cell stack;
said winding forming a rounded anode-separator-solid composite cathode subassembly having a jellyroll configuration and a rounded shape;
(c) removing said mandrel from said rounded subassembly;
(d) contacting said rounded subassembly with a source of liquid nonaqueous lithium salt electrolyte to form a rounded cell stack, wherein said electrolyte substantially fills porous areas within said rounded cell stack;
(e) compressing said rounded cell stack in a press to form said prismatic cell stack, wherein said electrolyte substantially fills porous areas within said prismatic cell stack;
(f) removing said prismatic cell stack from said press;
(g) enclosing said prismatic cell stack in a barrier material film;
and,
(h) sealing said film to form said casing.

16 more elements

Dependencies are inferred from the claim text.