Abstract
Elevated temperature is one of the biggest causes of degradation in lithium-ion batteries. In this study the effects of different cooling configurations were compared to the absence of a cooling solution for the common 18650 lithium-ion battery cells. The batteries were exercised through three hundred cycles of high current charge and discharge operations. There were three different test conditions for the 18650 batteries: no cooling, radially cooled, and axially cooled. The reduction in cell capacity was compared between each battery after testing and is the primary datapoint of interest. Temperature differentials were also recorded for each test. Internal battery construction greatly affects the effectiveness of axial cooling while radial cooling generally reduces battery cell temperature more consistently across the 18650 cells. Radially cooling due to the much larger surface area available for heat transfer maximizes temperature reduction under high stress situations and results in the lowest capacity loss. The effects of self-heating in lithium-ion batteries greatly reinforces the need for active thermal management in energy storage and electric vehicle applications to prolong cell life.