Electrode for electrochemical cells and composition thereof

Patent metadata

Field	Value
Publication number	US-2018040903-A1
Application number	US-201515527357-A
Country	US
Kind code	A1
Filing date	Dec 17, 2015
Priority date	Dec 19, 2014
Publication date	Feb 8, 2018
Grant date	—

Abstract

The present invention relates to an electrode for use in electrochemical cells and systems, such as rechargeable batteries, having a metal substrate and a catalytic coating applied onto the substrate. The catalytic coating has a mixture of noble metals or noble metal oxides and can be used to improve the energy efficiency of the cell.

First claim

1 . Electrode for use in electrochemical cells comprising:
a metal substrate; a catalytic coating comprising a mixture of noble metals or oxides thereof, wherein said mixture comprises 60-85% ruthenium, 0-25% iridium and 1-15% platinum in mole percentage referred to the elements.

2 . The electrode according to claim 1 wherein said mixture of noble metals or oxides thereof comprises 70-80% ruthenium, 17-25% iridium and 1-5% platinum in mole percentage referred to the elements.

3 . The electrode according to any one of the preceding claims, wherein the loading of ruthenium, iridium and platinum is 5 to 30 g/m 2 referred to the sum of the elements.

4 . The electrode according to any one of the preceding claims, wherein said metal substrate consists of a titanium material.

5 . The electrode according to claim 4 further comprising an intermediate layer containing titanium material applied between said metal substrate and said catalytic coating.

6 . The electrode according to any one of the preceding claims wherein said substrate has an average porosity of 40% to 60%.

7 . The electrode according to claim 4 wherein said titanium material comprises titanium suboxides according to the formula Ti x O y , wherein x is in the range of 2 to 10 and y is in the range of 3 to 19.

8 . Method for the production of an electrode according to any one of claims 2 to 7 comprising the following sequential steps:
applying a precursor solution comprising a mixture of ruthenium, iridium and platinum compounds in one or more coats over said metal substrate;
drying said metal substrate after each coating at a temperature of 80° C. to 150° C.;
thermally treating said dried metal substrate at a temperature of 350° C. to 600° C.

9 . The method according to claim 8 wherein the precursor solution is applied to said metal substrate in 3 to 8 coats.

10 . Process for energy storage comprising the following steps:
circulating a zinc bromide solution within at least one electrochemical cell; performing the electrolysis of said solution within said electrochemical cell; said electrochemical cell being equipped with at least one electrode according to any one of claims 1 to 7 , wherein said electrode alternately evolves and reduces bromine.

11 . The process according to claim 10 further comprising the execution of a periodic electric charge and discharge cycle on said electrochemical cell by means of an external electric circuit.

12 . Flow battery comprising at least one electrode according to any one of claims 1 to 7 .

13 . The flow battery according to claim 12 wherein said flow battery is a zinc/bromine flow battery and said at least one electrode alternately evolves and reduces bromine.

14 . The flow battery according to claim 12 wherein said flow battery is a hydrogen/bromine flow battery and said at least one electrode alternately evolves and reduces bromine.

15 . The flow battery according to claim 12 wherein said flow battery is an organic redox species/bromine flow battery and said at least one electrode alternately evolves and reduces bromine.

Assignees

• Industrie De Nora Spa

Inventors

• Allen Christopher J
• Abraham Sobha
• Hardee Kenneth L

Classifications

• H01M8/20

  Indirect fuel cells, e.g. fuel cells with redox couple being irreversible (H01M8/18 takes precedence) · CPC title

• H01M4/923

  Compounds thereof with non-metallic elements · CPC title

• H01M4/921 Primary

  Alloys or mixtures with metallic elements · CPC title

• H01M4/8842

  Coating using a catalyst salt precursor in solution followed by evaporation and reduction of the precursor · CPC title

• H01M8/0232

  Metals or alloys · CPC title