i.e. an assembly/module comprising various electrodes (at least cathode and anode) that can be inserted together as a single unit. The following example is from an English-language patent application for a "Pressurized electrolyzer stack module" (United States Patent Application 20080083614):

FIG. 3 is perspective view of an electrode insert for the electrochemical cell stack of FIG. 2.

As best shown in FIG. 3, the anode 102 , bipolar plate 106 and cathode 104 are joined together to create an electrode insert 108 . The electrochemical cell structure 100 (FIG. 2) further comprises an electrode frame 110 . The circularly shaped electrode frame 110 comprises an electrolyte inlet 112 , a first electrolyte flow path 114 on a top surface 116 , a second electrolyte flow path 117 on a bottom surface 118 (shown with dotted lines), a seat 120 , an oxygen flow path 122 on a top surface 116 and a hydrogen flow path 124 on a bottom surface 118 (shown with dotted lines). An electrode insert 108 is positioned on a seat 120 .

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