On the possible influence of the Fermi–Dirac statistics on the potential and entropy of galvanic cells

Abstract

The open circuit voltage of galvanic cells is temperature dependent and the effect responsible for this dependency is its entropy. While it is well known that the Nernst equation plays an important role in describing this temperature dependency of the open-circuit voltage, this paper displays another effect. Measurements of the entropy for lithium-ion batteries show a significant temperature dependency, which cannot be explained by the linear Nernst equation. But this temperature dependency can be described by the free electron potential adapting via Fermi–Dirac statistics. This approach results in a quadratic temperature dependence of the measured potentials, which in the here shown cases for commercial lithium ion cells, could explain the measured effect.