Revised theory of entropy and reversible energy flow in galvanic cells

According to the conventional theory, a reversible amount of heat is created or consumed in a reversible working galvanic cell. This heat is induced by the reaction entropy and occurs during current flow. The reaction entropy describes the change of the open circuit voltage due to a temperature change of the cell. The cells new equilibrium voltage is described by the Nernst equation. In this article, it is shown that such reversible heat is not in line with the second law of thermodynamics. Thus, a new theory was developed according to which the reversible heat does not exist. Instead, it is shown that the temperature changes in galvanic systems like lithium ion batteries result from a change of the total heat capacity in dependence of its state of charge, while the total heat remains constant. This change in heat capacity is generated through the internal particle transport. Overall, this leads to a general theory for the converted reversible energy and its power in galvanic cells.

Automated summary

This article challenges the conventional theory regarding reversible heat in working galvanic cells, proposing a new theory that reversible heat does not exist. Instead, it suggests that temperature changes in electrochemical systems are caused by variations in heat capacity depending on the state of charge. It concludes that the change in heat capacity is generated through internal particle transport, leading to a general theory for reversible energy and power conversion in galvanic cells.