Anode and/or cathode pan assemblies in an electrochemical cell, and methods to use and manufacture thereof

1. An electrochemical cell, comprising:

an anode pan assembly or a cathode pan assembly, or both, wherein the anode pan assembly or the cathode pan assembly, or both, comprises;

a pan configured to receive an electrolyte flowing through the pan;

one or more ribs positioned vertically inside the pan;

an electrode; and

a plurality of welds that weld the electrode to the one or more ribs, wherein the plurality of welds form a pattern comprising a distributed array of welds distributed across the electrode; and

an ion exchange membrane disposed between the anode pan assembly and the cathode pan assembly;

wherein a number, size, and positions of the plurality of welds are such that an impact of power dissipation on an internal temperature of the electrochemical cell is minimized to reduce membrane damage due to high local temperature.

2. The electrochemical cell of claim 1 , wherein a number of the one or more ribs inside the pan is from about 1 to about 75.

3. The electrochemical cell of claim 1 , wherein a thickness of the one or more ribs is from about 1 mm to about 3 mm; a height of the one or more ribs is from about 10 mm to about 110 mm; and/or a pitch between an adjacent pair of the one or more ribs is from about 40 mm to about 200 mm.

4. The electrochemical cell of claim 1 , wherein each of the one or more ribs comprises one or more notches and one or more ridges.

5. The electrochemical cell of claim 1 , wherein the electrode is a planar electrode or an expanded metal or a mesh.

6. The electrochemical cell of claim 1 , wherein each of the plurality of welds is in a form of a line, a spot, a pattern, or a combination thereof.

7. The electrochemical cell of claim 6 , wherein the number of the plurality of welds per rib in the form of the spots is from about 10 to about 50 welds per rib.

8. The electrochemical cell of claim 6 , wherein a distance between adjacent welds when in the form of spots is from about 25 mm to about 200 mm independently in an x-direction and a y-direction; the number of the plurality of welds per rib in the form of lines is from about 1 to about 75 welds per rib; and/or a distance between adjacent welds when in the form of lines is from about 40 mm to about 200 mm independently in the x-direction and the y-direction.

9. The electrochemical cell of claim 6 , wherein the pattern is selected from the group consisting of dots, an array of dots, dashes, spots, line segments, long lines, oval geometry, rectangular geometry, circular geometry, hexagonal geometry, and combinations thereof.

10. The electrochemical cell of claim 1 , wherein a cross sectional area of each weld is from about 6 mm 2 to about 3300 mm 2 .

11. The electrochemical cell of claim 1 , wherein a ratio of an electrode area relative to a total weld area is from about 15:1 to about 2000:1.

12. The electrochemical cell of claim 1 , wherein a current density through each weld is less than 6 A/mm 2 .

13. The electrochemical cell of claim 1 , wherein the electrochemical cell is a hydrogen gas producing electrochemical cell.

14. The electrochemical cell of claim 1 , wherein the number, size, and position of the plurality of welds are such that local heating of the electrolyte by the plurality of welds is to a temperature of 150° C. or less.

15. The electrochemical cell of claim 1 , wherein the number, size, and position of the plurality of welds are such that current across the electrode area is distributed to avoid local hot spots and/or to avoid large spatial or temporal temperature fluctuations of the electrolyte, or both.

16. A method, comprising:

positioning one or more ribs vertically inside an anode pan or a cathode pan, or both, of an electrochemical cell;

positioning an electrode on top of the one or more ribs;

welding the electrode to the one or more ribs with a plurality of welds, wherein the plurality of welds form a pattern comprising a distributed array of welds distributed across the electrode; and

positioning an ion exchange membrane between the anode pan and the cathode pan;

wherein a number, size, and position of the plurality of welds are such that an impact of power dissipation on an internal temperature of the electrochemical cell is minimized to reduce membrane damage due to high local temperature.

17. The method of claim 16 , wherein positioning the electrode on top of the one or more ribs comprises placing the electrode perpendicularly relative to the one or more ribs.

18. The method of claim 16 , wherein positioning the one or more ribs vertically inside the anode pan or the cathode pan, or both, comprises positioning from about 1 to about 75 ribs vertically inside the anode pan or the cathode pan, or both.

19. The method of claim 16 , wherein welding the electrode to the one or more ribs with the plurality of welds comprises providing each of the plurality of welds in a form of a line, a spot, a pattern, or a combination thereof.

20. The method of claim 16 , further comprising operating the anode pan or the cathode pan under a flow rate of anolyte through the anode pan or of catholyte through the cathode pan, or both, of from about 200 kg/h to about 10,000 kg/h; and operating the electrochemical cell at a current density of from about 300 mA/cm 2 to about 6000 mA/cm 2 .

21. The method of claim 16 , further comprising flowing an electrolyte through the pan and operating the electrochemical cell to generate hydrogen gas, wherein the number, size, and position of the plurality of welds are such that local heating of the electrolyte by the plurality of welds is to a temperature of 150° C. or less.

22. The method of claim 16 , wherein the number, size, and position of the plurality of welds are such that current across the electrode area is distributed to avoid local hot spots and/or to avoid large spatial or temporal temperature fluctuations of the electrolyte, or both.