Effect of thickness on the maximum potential drop of current collectors

TL;DR

This paper investigates how the thickness of current collectors influences the maximum potential drop in high-power electrochemical energy storage devices, highlighting the importance of optimizing thickness to reduce resistance.

Contribution

It introduces an electrical model that quantifies the impact of current collector thickness on potential drop, emphasizing the critical threshold around 500 micrometers.

Findings

Maximum potential drop remains constant above 500 μm thickness.

Potential drop increases sharply as thickness decreases below 500 μm.

Material and tab position also affect the potential drop.

Abstract

The basic principle for achieving high-power capability on an electrochemical energy storage cell is minimizing the overall resistance. The resistance due to current collecting systems has not received sufficient attention in the past, presumably because it was not considered of significance for low-power batteries and supercapacitors. However, the necessity of high-power cells has reduced other sources of the inner resistance, and the current collector potential drop has become more important. Moreover, the miniaturization of energy storage devices could increase the ohmic loses in current collectors. In this work, we have developed an electrical model to assess the effect of the current collector thickness on the maximum potential drop. We have found that the thickness of current collectors is a critical parameter that can increase the maximum potential drop drastically. Indeed, the maximum potential drop of current collectors remains almost constant for thicknesses greater than 500 lm, but below this value, there is an inverse relationship between the maximum potential drop and the thickness. We have also analyzed the effect of the material and tab position in the maximum potential drop.