Kovalyuk Z. D. UkraineChernivtsi Institute of Problems of Materials Science of I. N. Frantsevich NAN of Ukraine, Chernovitsky Branch Author's articles Properties of bismuth selenide as a cathode material for lithium power sources Impedance spectroscopy studies of Li/Bi2Se3 <1%Cu> system A carbonic material of vegetal raw materials for supercapacitor electrodes Pyrolized carbon electrode material for supercapacitors obtained from organic raw materials of vegetable nature