Effect of pH on Corrosion of Sintered Stainless Steels Used for Bipolar Plates in Polymer Exchange Membrane Fuel Cells / Wpływ Ph Roztworu Na Szybkosc Korozji Spiekanych Stali Nierdzewnych Stosowanych Na Okładki Ogniw Paliwowych Z Membrana Polimerowa

Abstract

WPŁYW pH ROZTWORU NA SZYBKOŚĆ KOROZJI SPIEKANYCH STALI NIERDZEWNYCH STOSOWANYCH NA OKŁADKI OGNIW PALIWOWYCH Z MEMBRANĄ POLIMEROWĄProton exchange membrane fuel cells (PEMFCs) are numbered among low-temperature cells. Their operating temperature reaches 120• C, whereas their efficiency amounts to ca. 40%. These cells are most often used for the batteries for portable devices, low and high power generators, stationary power plants and car drives. The PEMFCs are composed of the membrane, electrodes at both sides and bipolar plates, also termed interconnectors.The main aim of the present study was to investigate the sintered stainless steels in simulated environments of a PEM fuel cells for bipolar plates. The ferritic (434L) and austenitic (316L) stainless steels were examined. The corrosion properties were examined in 0.1 mol dm −3 Na 2 SO 4 + 2 ppmF − (pH= 1; 3; 5) at 80 • C. Keywords: fuel cell, bipolar plates, corrosion, sintered stainless steel, structural analysis, corrosion resistance Ogniwa paliwowe z membraną protonowymienną są jednym, z niskotemperaturowych ogniw. Ich temperatura pracy wynosi 120• C, a sprawność dochodzi do 40%. Tego typu ogniwa są najczęściej używane jako generatory do urządzeń przenośnych, małych i średnich stacjonarnych elektrowni i do napędu samochodowego. Ogniwa PEMFC (Proton Exchange Membrane Fuel Cell) składają się z membrany, elektrod po obu jej stronach oraz okładek, nazywanych też interkonektorami. Głównym celem niniejszej pracy było zbadanie spiekanych stali nierdzewnych przeznaczonych na okładki, w symulowanych środowiskach ogniw paliwowych PEMFC. Badano stal ferrytyczną (434L) oraz austenityczną (316L). Odporność korozyjna stali badano w 0.1 mol dm −3 Na 2 SO 4 +2 ppmF − (pH= 1; 3; 5) w temperaturze 80• C.

Porous Carbon Materials for Elements in Low-Temperature Fuel Cells

“…3. Figure shows a typical curves (volume vs. pressure curve) of a porous material with a hysteresis loop that is typical for spherical pores (Sintered Graphite) [15,[16][17][18]. The curves obtained for Toray Teflon and Graphite Grade, indicates that the pore shape are plate.…”

“…The significant part of the PEM-FC stack is the bipolar plates, which account for about 80% of total weight [1] and 45% of generator cost [2]. The requirements for a bipolar plate material are good thermal and electric conductivity, chemical stability in anodic and cathodic environ-mental, lightweight, inexpensive and easily manufactured [3,16]. By many authors, the ideal material for bipolar plates is graphite despite its brittleness and lack of mechanical strength or composites based on graphite [4][5][6].…”

Corrosion analysis of graphite sinter as bipolar plates in the low-temperature PEM fuel cell simulated environments

“…As a result of the conducted research, it was observed that transitional processes in which the intermediate product was CO, the reduction of the specific surface of the catalyst caused by gas absorption was indicated, difficulties in diffusion of gases through the diffusion layer (made of carbon materials) of the electrodes were observed [25,26]. The above problems are eliminated by the use of platinum alloys with metals of transition groups in order to bind the carbon monoxide CO deposited on the platinum surface [27][28][29][30].…”

Properties of graphite-stainless steel composite in bipolar plates in simulated anode and cathode environments of PEM fuel cells

“…Products of corrosion of BP materials might poison the catalysts and decrease the efficiency of the fuel cell [39][40][41]. The working electrode was based on composite, the reference electrode was based on a saturated calomel electrode (SCE), and the auxiliary electrode was based on a Pt wire.…”