Solid polymer electrolyte General Electric

Nuttall, L. J., "Water Electrolysis Using Solid Polymer Electrolytes", General Electric Co., Presented at the Institute of Gas Technology s "Hydrogen for Energy Distribution Symposium", July 24-28, 1978. 

The PEFC was first developed for the Gemini space vehicle by General Electric, USA. In this fuel cell type, the electrolyte is an ion-exchange membrane, specifically, a fluorinated sulfonic acid polymer or other similar solid polymer. In general, the polymer consists of a polytetrafluoroethylene (Teflon) backbone with a perfluorinated side chain that is terminated with a sulfonic acid group, which is an outstanding proton conductor. Hydration of the membrane yields dissociation and solvation of the proton of the acid group, since the solvated protons are mobile within the polymer. Subsequently, the only liquid necessary for the operation of this fuel cell type is water [7,8],... 

Two cases were examined for the production of water electrolysis. Data were taken from Reference (1) and adjusted to mid-1979 levels in accordance with Table 1. The costs of "current technology" electrolysis were averaged in Reference (1) from information provided by Lurgi, Electrolyser Corp., General Electric, and Teledyne Isotopes. An advanced electrolyzer design, based upon the General Electric Solid Polymer Electrolyte (SPE) design, was also addressed as the second case. 

Russell, J.H., Sedlak, Dr. J.M., General Electric Company, Direct Energy Conversion Programs, Economic Comparison of Hydrogen Production Using Solid Polymer Electrolyte Technology for Sulfur Cycle Water Decomposition and Water Electrolysis, EPRI Research Project 1086-3, Final Report, December 1978. 

The idea of using an ion-conductive polymeric membrane as a gas-electron barrier in a fuel cell was first conceived by William T. Grubb, Jr. (General Electric Company) in 1955. - In his classic patent, Grubb described the use of Amber-plex C-1, a cation exchange polymer membrane from Rohm and Haas, to build a prototype H2-air PEM fuel cell (known in those days as a solid-polymer electrolyte fuel cell). Today, the most widely used membrane electrolyte is DuPont s Nation... 

The concept of using an ion-exchange membrane as an electrolyte in electrochemical cells was first introduced by Grubb in 1959. Since then, extensive research and development programs have been undertaken by the General Electric Company and others,resulting in the present solid polymer electrolyte (SPE) cells in which Nafion serves as the sole electrolyte as well as separator. High voltaic efficiency can be achieved in SPE cells because of the minimum contact resistance between electrode and separator. 

The development of solid polymer electrolyte cells is being actively conducted at General Electric Co. (13) and at Brown Boveri Research Center, Baden, Switzerland (14). As the name implies, the solid polymer electrolyte technology uses a solid polymer sheet as the sole electrolyte in the cells. It also acts as the cell separator. The majority of the present applications use Nafion with a thickness of 10-12 mils (13). Selected physical and chemical properties of Nafion 120 membranes are given in Table I. The membrane is equilibrated in water to approximately 30% water content prior to fabrication into a cell assembly. The hydrated membrane is highly conductive to hydrogen ions. It has excellent mechanical strength, and it is very stable in many corrosive cell environments. 

McElroy, J.F., (General Electric Company), Status of Solid Polymer Electrolyte Fuel Cell Technology, G.E. Direct Energy Conversion Program, Rep. (undated). 

In the 1960s, the use of solid-state polymer electrolytes instead of the liquid electrolytes normally used in alkaline electrolysis led to the development of novel concepts for water electrolysis. The US company General Electric was the first to realize solid polymer electrolyte water electrolysis (SPE) with the aid of the solid polymer electrolyte membrane (Nafion ) developed by DuPont [16]. At the same time, ABB [17, 18] in Switzerland and Fuji Electric [19] in Japan also developed PEM electrolyzers with single electrode areas of up to 2500 cm. These... 

A particular approach adopted by General Electric In U.S.A. is the solid polymer electrolyte (SPE) cell in which the porous cloth-type separator is replaced by a polymeric ion exchange membrane which is conductive to cations (Figure 5). The particular membrane employed, NAFION, is a perfluorsulphonlc acid pol3nner which is extremely stable in both acid alkaline solution. Appropriate electrocatalysts are coated on each face of the polymer sheet and these are contacted by a metal mesh current collector. Further research is aimed at reducing the cost and improving the electrical efficiency of the system to make it competitive with conventional electrolyzers. 

Fig. 5. Schematic of General Electric solid polymer electrolyte cell.

During these programs, PME fuel cells and electrolyzers were developed. These first solid membranes were made of sodium polystyrene sulfonate, and would be replaced by Nafion, which was discovered by DuPont in the same decade. Thus, it was in 1966 that the very first solid-polymer electrolyte (SPE) electrolyzer was built by General Electric (GE) for Project GEMINI to produce oxygen on board the spacecraft. 

DeNora and General Electric are developing an electrolyzer with a solid polymer electrolyte (SPE) based on Nafion [196]. In addition to a voltage savings of 20%, it is hoped that completely chloride-ffee hydrogen gas can be produced. 

Solid polymer acid electrolytes were first developed for fuel cell applications in the late 1950 s by the General Electric Company (GE), which initiated a program to develop membrane cells and electrolyzers. The first membranes developed by GE for fuel cell applications were made by the condensation of phenolsulfonic acid and formaldehyde. These membranes were found to be brittle, prone to cracking when dried, and rapidly hydrolyzed... 

The polymer electrolyte membrane fuel cell (PEMFC) also known as proton exchange membrane fuel cell, polymer electrolyte fuel cell (PEFC) and solid polymer fuel cell (SPFC) was first developed by General Electric in the USA in the 1960 s for use by NASA in their initial space applications. The electrolyte is an ion conducting polymer membrane, described in more details in Section 2.2. Anode and cathode are bonded to either side of the membrane. This assembly is normally called membrane electrode assembly (MEA) or EMA which is placed between the two flow field plates (bipolar plates) (Section 2.5) to form what is known as stack . The basic operation of the PEMFC is the same as that of an acid electrolyte cell as the mobile ions in the polymer are or proton. 

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