Electrical energy storage devices with separator between electrodes and methods for fabricating the devices
Films of active electrode material, such as films made from carbon and fibrillized polymer, are attached to a porous separator. Outer surfaces of the films (i.e., surfaces opposite those adjoining the separator) are then covered with current collectors. The 5 resulting stack is usable in fabrication of electrical energy storage devices. The stack can be shaped as needed, connected to terminals, and immersed in an electrolytic solution to provide a double layer capacitor.
1. A double layer capacitor product comprising:
a first layer of electrode material comprising a first surface and a second surface;
a second layer of electrode material comprising a third surface and a fourth surface;
a porous separator disposed between the first layer and the second layer so as to adjoin and be attached to the first surface and the third surface;
a first current collector attached on the second surface; and
a second current collector attached on the fourth surface;
wherein
the separator is attached to the first surface before the first current collector is attached to the second surface; and wherein
the separator is attached to the third surface before the second current collector is attached to the fourth surface.
2. The double layer capacitor product of claim 1 wherein the electrode material comprises dry activated carbon particles, dry polymer and dry conduction promoter particles that are processed into the electrode material in a dry process.
3. The double layer capacitor product of claim 1 wherein the electrode material is self-supporting.
4. The double layer capacitor product of claim 1 wherein the separator is attached to the first and third surface before either current collector is attached to a surface.
5. The double layer capacitor product of claim 4 , wherein the separator is attached to the first and third surface in the same process step.
6. The double layer capacitor product of claim 1 wherein the separator and attached electrode films are laminated together before the current collector is attached to either surface.
7. The double layer capacitor product of claim 1 wherein there is a layer of adhesive between the first surface and separator and the third surface and the separator.
8. The double layer capacitor product of claim 1 wherein there is a layer of adhesive between the first current collector and the second surface and a layer of adhesive between the second current collector and the fourth surface.