Temperature Dependence of Open Circuit and Decomposition Potentials

16 TEMPERATURE DEPENDENCE OF OPEN CIRCUIT AND DECOMPOSITION POTENTIALS 

Note that the temperature dependence of the standard OCP and DP is very important for estimating the efficiency of the electrochemical systans vs. efficiency of a heat engine. For example, the theoretical (thermodynamic) efficiency of Hj/Oj fuel cell decreases when temperature increases, and the theoretical efficiency of C/O2 fuel cell does not significantly change over a wide temperature range. In contrast, the thermodynamic efficiency of a heat engine always increases when temperature increases. The efficiency of fuel and electrolytic cells will be considered later in Chapter 8. 

FIGURE 4.3 Temperature dependence of the standard OCP for Hj/Oj, C/Oj, and H2/CI2 fuel (galvanic) cells. The calcnlations were carried out using the data from [Chapter 10, Table 10.4]. 

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