Flexible Thin Printed Battery and Device and Method of Manufacturing Same
A flat, flexible electrochemical cell is provided. The within invention describes various aspects of the flat, flexible electrochemical cell. A printed anode is provided that obviates the need for a discrete anode current collector, thereby reducing the size of the battery. An advantageous electrolyte is provided that enables the use of a metallic cathode current collector, thereby improving the performance of the battery. Printable gelled electrolytes and separators are provided, enabling the construction of both co-facial and co-planar batteries. Cell contacts are provided that reduce the potential for electrolyte creepage in the flat, flexible electrochemical cells of the within invention.
1 . A thin, flexible battery comprising a positive electrode, a negative electrode, a separator and an electrolyte contained within a sealed housing, wherein:
the housing comprises a flexible, electrically nonconductive substrate;
at least one of the positive electrode and the negative electrode is a printed electrode on a portion of the substrate;
the positive electrode being in physical contact with a positive electrode current collector; and
the positive electrode current collector comprises an electrically conductive metal coated with an electrically conductive film comprising a carbon.
2 . The battery according to claim 1 , wherein the electrically conductive metal comprises silver or aluminum.
3 . The battery according to claim 1 , wherein the film further comprises a binder.
4 . The battery according to claim 3 , wherein the positive electrode current collector is disposed on the substrate and the film comprises an ink and is printed onto the positive electrode current collector.
5 . The battery according to claim 1 , wherein the positive electrode current collector is a metal current collector.
6 . The battery according to claim 1 , wherein the positive electrode current collector is a printed metallic current collector comprising a metallic ink.
7 . The battery according to claim 1 , wherein the electrolyte is an acidic electrolyte.
8 . The battery according to claim 7 , wherein the electrolyte comprises at least one of zinc chloride, ammonium chloride, zinc acetate and ammonium acetate.
9 . The battery according to claim 1 , wherein the electrolyte is an alkaline electrolyte.
10 . The battery according to claim 1 , wherein the separator comprises a paper.
11 . The battery according to claim 1 , wherein the electrolyte comprises a gelled electrolyte.
12 . The battery according to claim 11 , wherein the gelled electrolyte comprises a material selected from the group consisting of a polyethylene glycol based polymer, nonionic or anionic derivatives with natural guar gum, polyethylene oxide, a copolymer comprising acrylic or methacrylic acid and styrene sulphonate, and a non-polymeric thixotropic gelant.
13 . The battery according to claim 12 , wherein the gelant comprises a fumed silica.
14 . The battery according to claim 1 , wherein the battery comprises a gas inhibiting material comprising
a member of the group consisting of cetyltrimethylammonium bromide; a polymer having a phosphate group and chains comprising polyethylene oxide; and combinations thereof.
15 . The battery according to claim 1 , wherein the negative electrode comprises zinc and the positive electrode comprises manganese dioxide.
16 . The battery according to claim 15 , wherein the negative electrode comprises a zinc foil or zinc mesh.
17 . The battery according to claim 15 , wherein the negative electrode comprises a zinc ink, the zinc ink comprises a mixture of a zinc powder and a binder.
18 . The battery according to claim 17 , wherein the zinc ink binder comprises a member of the group consisting of polyethylene oxide and polyvinylpyrrolidone.
19 . The battery according to claim 1 , wherein the positive and negative electrodes are coplanar electrodes.
20 . A carbon zinc battery comprising a positive electrode, a negative electrode, a separator and a positive electrode current collector, wherein the positive electrode current collector comprises a metallic substrate or a metallic ink and a protective carbon coating on the metallic substrate or metallic ink.