Multi-stack electrolyzer module
The present invention relates to modular packages of individual electrolyzer stack units arranged to overcome prior art limitations related to power supply costs, as-manufactured stack unit performance variation, operating stack unit performance variation, and operational reliability. The electrolyzer stack module comprises an even number of individual stack units wired in series-parallel and arranged to minimize variation between branches of series-connected stack pairs.
1 . A method of assembling an electrolyzer module comprising providing a plurality of stack units;
testing each of the plurality of stack units to determine one or more performance parameters of said stack units;
ranking each of the plurality of stack units by one or more of the performance parameters measured;
determining branch pairing by pairing the best performing stack unit remaining with the worst performing stack unit remaining until all stacks have been assigned to a pair;
assembling the electrolyzer module by electrically connecting the paired stack units in series to form a plurality of branches, and electrically connecting the plurality of branches in parallel.
2 . The method of claim 1 , wherein the stack units are arranged in stack branches and stack banks in such a way to minimize electrical impedance variation between the branches.
3 . The method of claim 1 , wherein the one or more performance parameters are selected from the group consisting of a voltage at an applied current, a current at an applied voltage, and a hydrogen production rate at an applied current.
4 . The method of claim 1 , wherein each of the plurality of stack units has a mass of less than or equal to 2,000 kilograms.
5 . The method of claim 1 , wherein each of the plurality of stack units has a power consumption of between 250 kilowatts and 5 megawatts.
6 . The method of claim 1 , wherein the total number of stack units is less than or equal to 48.
7 . The method of claim 1 , wherein the plurality of stack units are arranged within a standard ISO container of 40 feet or less in length.
8 . The method of claim 1 , wherein the total number of stack units is an even number, and wherein the paired stack units form branches with two (2) stack units per branch.
9 . The method of claim 8 , wherein the stack units in a first stack bank are installed upside down relative to the stack units in a second stack bank.
10 . The method of claim 1 , wherein testing each of the plurality of stack units comprises measuring a voltage at an applied current density.
11 . The method of claim 1 , wherein testing each of the plurality of stack units comprises measuring a current density at an applied voltage.
12 . The method of claim 1 , wherein testing each of the plurality of stack units comprises measuring a hydrogen production rate at an applied current.
13 . The method of claim 1 , wherein the method further comprises periodically repeating the steps of determining one or more operating performance parameters, determining new branch pairings, and rearranging the plurality of stack units during operation of the electrolyzer module.
14 . The method of claim 1 , wherein the performance parameters are measured using end-of-line quality control testing.