An overvoltage phenomenon was investigated that occurs during partial charge-discharge experiments for LiFePO_4 as electrode material showing a plateau-like behavior. The temperature was varied in order to determine the influence on the voltage change (overvoltage). This overvoltage effect was recently reported by another group and discussed in light of a many-particle model. However these measurements were carried out only at room temperature. Hence temperature influence was supposed to be worth of consideration. Indeed, an increased overvoltage was observed at lower temperature, while an opposite effect was obtained at higher temperature. Increasing the number of partial charge-discharge cycles leads to an interference of single voltage bumps, but the overvoltage seems to saturate at a given voltage level.
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