The main requirement to the materials used to make membranes polymer electrolyte membrane fuel cells (PEM FC) is the combination of high proton conductivity and resistance to the FC operation conditions. Thus, the search for inexpensive and high-performance non-fluorinated or partially fluorinated materials for use as FC membranes is an actual task today, since the use of membranes based on perfluorosulfonate acid has a number of disadvantages limiting their application. The aim of this study

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... the investigation of sulfonated polyimide (SPI) and materials for use as FC membranes. The relevance of research stems from the fact that the use of the SPI will allow to increase the resistance of the membrane to the constantly changing environment in which PEM operates. The objects of research are sulfonated polyimides. SPIs, especially aromatic SPIs, are attractive to researchers, because of the possibility of obtaining a wide variety of chemical structures and also due to their excellent thermal, mechanical properties and high resistance to aggressive media. The results of this study will be methods of obtaining and evaluating the advantages and disadvantages of SPI-based materials. For the first time, special attention will be paid to advanced development based on SPI with the addition of crown-ether fragments. into electrical energy. In an ideal fuel cell, electrolyte and electrodes are not consumed and do not undergo any changes during the operation process -the chemical energy of fuel is converted directly into electricity. The FC device is similar to the device of the galvanic cell. The main part of any fuel cell is the membrane-electrode assembly (MEA), which is a solid electrolyte layer with the applied electrodes. One side of the membrane (similar to liquid electrolyte in the galvanic element) is applied to the cathode and the other anode catalytic layers. Most often, the catalyst of the anode, molecular hydrogen dissociates and loses electrons. Cations of hydrogen are conducted through the membrane to the cathode, but the electrons are given to the external circuit because the membrane does not pass electrons. On the catalyst of the cathode, the oxygen molecule joins with an electron supplied from an external communications and with arrived proton to form water, which is the only product of the reaction. The current collecting at the cathode and anode sides, a supply source of reagents and withdrawal of the reaction products is carried through the porous gas diffusion layers (GDL), is usually made of carbon materials. There are several different types of fuel cells classified according to the type of electrolyte. The type of the electrolyte depends on the most parameters of the FC, such as operating temperature, size, energy output, etc. Fuel cells based on polymer electrolyte (proton-exchange) membrane (PEM) is designed to become compact sources of energy and replace petrol and diesel engines. These systems operate at relatively low temperatures up to 100°C. They quickly go on working power, and are compact, which is advantageous for use in transport. The main, and still not overcome the disadvantage of this type of FC is a weak resistance of the membrane to constantly changing environment in which operate PEM. Membrane PEM FC works in conditions of constantly changing temperatures, high humidity, organic reagent and the formation of peroxides. The main requirement to the materials used to make membranes is the combination of high proton conductivity and resistance to the conditions of the FC. An important criterion is also the low cost of their production. The first electrolytic membrane, which was developed by General Electric in the USA in the late 1960s to FC used in spacecraft of the Gemini, was sulfonated copolymer poly-(styrenedivinylbenzene). This polymer was not sufficiently resistant to oxidation under operating conditions of FC. A major breakthrough in technology proton-conducting membranes for fuel cells was the emergence of perfluorosulfonate acid (PFSA) Nafion -DuPont product obtained in the 1970s and Nafion counterparts from other firms, for example, Flemion ® (Asahi Glass), DowMembrane ® (Dow Chemical) and Aciplex ® (Asahi Chemical). However, the own proton conductivity of such membranes is extremely small, and effectivity proton transfer is determined by the presence of adsorbed atmospheric moisture. Moreover, the market value of the Nafion membranes is 700-800$/m 2 . Despite the fact that PFSA are still excellent materials for membrane fuel cells, yet they have several significant shortcomings that limit their widespread application. These factors stimulate Perspective Non-Fluorinated and Partially Fluorinated Polymers for Low-Temperature PEM FC http://dx.