Influence of current collecting tab design on thermal and electrochemical performance of cylindrical Lithium-ion cells during high current discharge

Lithium-ion cells with high-power design are particularly interesting due to their ability to deal with high current loads. In the present study, modified commercial 26650-type high-power Lithium-ion cells with LiFePO4 cathodes and graphite anodes are investigated regarding their thermal and electrochemical performance during discharge with currents up to 10 C (=25 A). The investigated cells contain four current collecting tabs for both, anode and cathode. The 26650 cells are modified by inserting a temperature sensor into the cylindrical hole of the jelly roll and regarding their number of tabs at the positive connection. This way, model cells are created to investigate the influence of the current collecting tab design via operando measurements. The dependence of the maximum temperatures and radial temperature gradients in the cell as well as the rate capability is investigated quantitatively. (C) 2015 Elsevier Ltd. All rights reserved.