Design and development of a battery internal short circuit testmachine

The use of lithium-based batteries, due to their high energy density, has become popular for power sources in portable electronic devices. Safety concerns over lithium cell applications have arisen due to their lower abuse tolerance compared to standard battery designs. Internal short circuits present one of the more dangerous abuse situations since there is a great potential of thermal runaway leading to fire and explosion. Field failures and recalls associated with internal short circuits demonstrate the risks of lithium batteries. Understanding the response of lithium cells under internal short circuit conditions is of great importance to ensure the safe development of lithium battery application. In this work, an internal short circuit test machine was designed to conduct nail penetration tests of lithium chemistry cells. The test machine successfully provides the required force to allow for multi-cell penetration. The test machine also provides accurate control of the penetrating nail's position and velocity. This testing will support the development of models to simulate the mechanism of internal short circuits of lithium cells.