During charge/discharge, there is overpotential (relative to the Cell open-circuit voltage) in the end of the process. This is due to ion diffusion and the gradient of potential in particles. The overpotential effect is greater for an electrode material with lower ion diffusion rate. Cell diffusion voltage is caused by the same physical process, but it's more salient at the end of the charge or discharge process than during the cell state-of-charge — Cell open-circuit voltage dependency plateau.

Overpotential also depends on the Cell internal resistance.

The overpotential at the end of discharge is 0.06 V for LTO anode and 0.03 V for graphite anode.

Overpotential is usually included in the cell min/max voltage specifications of a cell.

The ion diffusion in the electrolyte also contributes to the overall overpotential during a discharge or charge process.

Overpotential is a symptom of the energy losses in the battery cell: extra work needs to be done during charging (because voltage is higher) and less work could be done against load during discharge (because voltage is lower).

Because overpotential is higher at the end of charge and discharge, it's more efficient to cycle battery only within the potential "plateau".

Overpotential at the end of charge/discharge process shouldn't be confused with Cell voltage hysteresis: the difference in charge and discharge potential, caused by other factors, such as polarisation of electrode material, and the difference in the intercalation energies.

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Related:

References

Comparison of Lithium-Ion Anode Materials Using an Experimentally Verified Physics-Based Electrochemical Model

Understanding electrochemical potentials of cathode materials in rechargeable batteries