Lithium-ion battery has the risk of internal short circuit due to the influence of many factors such as material system and manufacturing process. Although lithium-ion batteries have been strictly aging and self-discharge screening at the factory, due to process failure and other unpredictable use factors, there is still a certain probability of failure leading to internal short circuit during use. For the power battery, the lithium-ion battery pack has as many as hundreds or even tens of thousands of batteries, greatly amplifying the probability of the battery pack occurring short. Due to the great energy contained in the power battery pack, the occurrence of internal short circuit is easy to induce vicious accidents, resulting in casualties and property losses. TE's PPTC and HPP-TA family of products provide a possible solution to prevent the occurrence of a serious accident in the event of an internal short circuit in the power battery.
    For the parallel lithium-ion power battery module, when one or several batteries have a short time, other batteries in the battery module will discharge it, and the energy of the battery pack will make the temperature of the short battery rise rapidly, which is easy to induce thermal runaway, and eventually lead to the battery fire and explosion. As shown in Diagram 1