Impedance hodographs for the test langatate electrochemical cells grown in different atmospheres and having different current conducting coatings: (a) Ar + (2%) O2, Au ((1) T = 20 °C; (2) 50; (3) 100; (4) 150; (5) 200; (6) 250; (7) 300; (8) 350; (9) 400; (10) 450); (b) Ar + O2, Ir ((1) T = 20 °C; (2) 100; (3) 150; (4) 200; (5) 250; (6) 300; (7) 350; (8) 400; (9) 450); (c) Ar, Au(Ti) ((1) T = 20 °C; (2) 50; (3) 100; (4) 150; (5) 200; (6) 230; (7) 400; (8) 450); (d) Ar, Ir ((1) T = 20 °C; (2) 50; (3) 100; (4) 150; (5) 200; (6) 250; (7) 300; (8) 350; (9) 400).