Electrochemical Cell With A Catalytic Electrode And Process For Making The Electrode And The Cell

Abstract

A process for making a catalytic electrode containing a transition metal nano-catalyst without using spray or thermal decomposition, and a process for making an electrochemical cell with a catalytic electrode. The nano-catalyst is a particulate material that includes particles that are at least partially oxidized, preferably to include at least oxide shells, before mixing with an activated carbon and binder in a liquid medium to adhere particles of the nano-catalyst to internal and external surfaces of the particles of activated carbon. Oxidation of the nano-catalyst particles allows the mixing of the nano-catalyst, activated carbon and binder in air rather than an inert gas atmosphere and can avoid the use of potentially dangerous liquid media such as highly volatile alcohols.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application claims the benefit of U.S. Provisional Application No. 60 / 877,251, filed Dec. 27, 2006.BACKGROUND[0002]This invention relates to a catalytic electrode, particularly an electrode with a nano-catalytic material, an electrochemical cell containing the catalytic electrode, and processes for making the catalytic electrode and the electrochemical cell.[0003]There is a wide variety of electrochemical cells that have catalytic electrodes. Examples include, but are not limited to, fuel cells, metal-air battery cells, gas (e.g., hydrogen) generating cells, and electrochemical sensor cells. Examples of such cells are found in U.S. Pat. Nos. 5,242,565; 5,308,711; 5,378,562; 5,567,538; 5,707,499; 6,060,196; 6,461,761; 6,602,629; 6,911,278; 7,001,689 and 7,001,865; and in International Patent Publication No. WO 00 / 36677.[0004]An advantage of cells with catalytic electrodes is that they can use one or more active materials that are not ...

AI Technical Summary

Benefits of technology

[0008]Some disclosed embodiments provide a process for manufacturing a catalytic electrode and / or an electrochemical cell using the catalytic electrode in an easy, economical and safe manner. Some embodiments eliminate the need for mixing in an inert atmosphere the components of the catalytic material or the resultant catalytic composition used to make the active layer of the electrode. Some embodiments eliminate the use of liquids that are highly volatile, flammable and / or explosive, that may pose potential health risks to workers, or that may pose a risk to the environment.

[0009]Some embodiments provide a catalytic electrode with a nano-catalyst material that has improved electrical properties and that will work well in an electrochemical cell when operated at high power.

[0010]Some embodiments provide an electrochemical cell that has good leakage resistance and improved performance (e.g., greater energy density, improved discharge capacity, and higher power on discharge) than cells made according to the prior art and is also stable during periods of storage and non-use.

Problems solved by technology

This places restrictions on and adds cost to the manufacturing process that can be undesirable, especially for large scale, high speed manufacturing.

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