Electrical energy storage devices with separator between electrodes and methods for fabricating the devices
View Patent ↗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.