IP Library Granted Patent US 12,703,920
Granted Patent B2
US 12,703,920 · App. 18/170,006 · Granted Aug 11, 2026

Electrolyzer stack end plate assembly with fluid-isolating insert(s)

Inventors: Matthew Sweetland (Latham, NY); Cortney Mittelsteadt (Latham, NY)
Assignee: Plug Power Inc.
C25B1/04C25B9/73
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Quick Facts
Patent No.
US 12,703,920
App. No.
18/170,006
Filed
Feb 16, 2023
Granted
Aug 11, 2026
Kind
B2
Art Unit
1794
USPC
205/628
Abstract

Electrolyzer systems and end plate assemblies are provided with one or more fluid-isolating inserts. The electrolyzer system includes a stack of electrolyzer cells, a current collector, an end plate assembly, and an isolation plate positioned between the end plate assembly and current collector. The end plate assembly includes at least one fluid channel to allow fluid to pass therethrough, where the fluid channel(s) is in fluid communication with at least one fluid channel through the current collector and isolation plate. The end plate assembly includes an end plate and an fluid-isolating insert residing, at least in part, within a pocket in the end plate. The fluid-isolating insert includes at least one electrically-isolating fluid channel that defines, at least in part, the fluid channel(s) of the end plate assembly, where the fluid-isolating insert increases an effective length of a fluid conduction path between the current collector and the end plate.

Claims (18)

1 . An electrolyzer system comprising:

a stack of at least one electrolyzer cell, the stack further including:

a current collector of the at least one electrolyzer cell;

an end plate assembly;

an isolation plate, the isolation plate being positioned between the end plate assembly and the current collector to electrically isolate the current collector from the end plate assembly; and

wherein the end plate assembly includes at least one fluid channel to allow a fluid to pass through the end plate assembly, the at least one fluid channel being in fluid communication with at least one fluid channel through the current collector and the isolation plate, and wherein the end plate assembly comprises:

an end plate; and

a fluid-isolating insert residing, at least in part, within a pocket in the end plate, the fluid-isolating insert including at least one electrically-isolating fluid channel that defines, at least in part, the at least one fluid channel of the end plate assembly, the fluid-isolating insert increasing an effective length of a fluid conduction path between the current collector and the end plate through the at least one fluid channel of the end plate assembly.

2 . The electrolyzer system of claim 1 , wherein the pocket in the end plate extends into the end plate from a surface of the end plate closest to the isolation plate.

3 . The electrolyzer system of claim 2 , further comprising a seal disposed, in part, within a groove in one of the isolation plate or the fluid-isolating insert at an interface of the isolation plate and fluid-isolating insert within the stack.

4 . The electrolyzer system of claim 3 , wherein a gap exists in the pocket between the fluid-isolating insert and the end plate, and the fluid fills the gap between the fluid-isolating insert and the end plate, which facilitates pressure-balancing opposite sides of the seal.

5 . The electrolyzer system of claim 3 , further comprising a pressure-containment seal disposed between the fluid-isolating insert and the end plate of the end plate assembly.

6 . The electrolyzer system of claim 3 , further comprising a conductive insert disposed between the fluid-isolating insert and the end plate within the pocket, the conductive insert defining, in part, the at least one fluid channel of the end plate assembly.

7 . The electrolyzer system of claim 6 , wherein the conductive insert comprises a platinum material which causes a localized electrolysis reaction at the conductive insert within the at least one fluid channel of the end plate assembly.

8 . The electrolyzer system of claim 6 , wherein a gap exists in the pocket between the fluid-isolating insert and the end plate, and the fluid fills the gap between the fluid-isolating insert and the end plate, which facilitates pressure-balancing opposite sides of the seal.

9 . The electrolyzer system of claim 6 , further comprising a pressure-containment seal disposed between the fluid-isolating insert and the end plate of the end plate assembly.

10 . The electrolyzer system of claim 2 , wherein the end plate assembly includes a plurality of fluid channels and manifold to allow the fluid to pass through the end plate assembly via the manifold of the end plate assembly, the plurality of fluid channels of the end plate assembly being in fluid communication with a plurality of fluid channels through the current collector and the isolation plate, and wherein the fluid-isolating insert includes a plurality of electrically-isolating fluid channels that define, at least in part, the plurality of fluid channels of the end plate assembly, the fluid-isolating insert increasing effective length of fluid conduction paths between the current collector and the end plate through the plurality of fluid channels of the end plate assembly.

11 . The electrolyzer system of claim 2 , wherein the end plate facilitates supplying a clamping force to the electrolyzer stack, and the fluid-isolating insert satisfies pressure containment restrictions within the electrolyzer stack.

Assignments (3)
RELEASE OF SECURITY INTEREST Recorded Nov 25, 2025
From: YA II PN, LTD., IN ITS CAPACITY AS COLLATERAL AGENT
To: PLUG POWER, INC.; PLUG POWER HYDROGEN HOLDINGS, INC.; UNITED HYDROGEN GROUP INC.; PLUG PROJECT HOLDING CO., LLC; PEACHTREE RENEWABLES, LLC; JOULE PROCESSING LLC; APPLIED CRYO TECHNOLOGIES, INC.; ALLOY CUSTOM PRODUCTS, LLC; HYPULSION U.S. HOLDING, INC.
Reel/Frame 073036/0448 →
SECURITY INTEREST Recorded Apr 28, 2025
From: PLUG POWER INC.; APPLIED CRYO TECHNOLOGIES, INC.; PLUG POWER HYDROGEN HOLDINGS, INC.; UNITED HYDROGEN GROUP INC.; ALLOY CUSTOM PRODUCTS, LLC; JOULE PROCESSING LLC; PEACHTREE RENEWABLES, LLC; PLUG PROJECT HOLDING CO., LLC; HYPULSION U.S. HOLDING, INC.
To: YA II PN, LTD., IN ITS CAPACITY AS COLLATERAL AGENT
Reel/Frame 071084/0264 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 16, 2023
From: SWEETLAND, MATTHEW; MITTELSTEADT, CORTNEY
To: PLUG POWER INC.
Reel/Frame 062719/0497 →