30 amp screw in resettable fuse_mini cooper fuse box factory

20 2024-08

　　Short circuit protection solution for lithium-ion battery packs

　　Lithium ion batteries are at risk of internal short circuits due to various factors such as material systems and manufacturing processes. Although lithium-ion batteries undergo strict aging and self discharge screening before leaving the factory, there is still a certain probability of failure due to process failures and other unpredictable usage factors, leading to internal short circuits during use. For power batteries, there are hundreds or even tens of thousands of lithium-ion batteries in the battery pack, greatly increasing the probability of internal short circuiting in the battery pack. Due to the enormous energy contained within the power battery pack, the occurrence of internal short circuits can easily trigger malignant accidents, resulting in casualties and property losses. TE's PPTC and MHP-TA series products provide a possible solution to prevent malignant accidents in the event of an internal short circuit in the power battery.

　　For parallel lithium-ion power battery modules, when one or several batteries experience a short period of time, other batteries in the battery module will discharge them, and the energy of the battery pack will cause the temperature of the short battery to rise rapidly, which can easily lead to thermal runaway and ultimately cause the battery to catch fire and explode.

　　Conventional temperature detection can inform the IC to cut off the main circuit when the battery is heating up, but it cannot prevent continuous discharge inside the parallel battery module. Moreover, due to the cutting off of the main circuit, all energy in the battery module is concentrated in the internally short circuited battery, which increases the probability of thermal runaway.

　　The ideal solution is to cut off the connection circuit between a certain battery and other batteries in the module when it is found to have an internal short and temperature rise. Assembling TE PPTC or MHP-TA series products on a single battery can effectively block the connection between the internal short-circuit battery and other batteries in the module when an internal short circuit occurs, preventing the occurrence of malignant accidents. For power battery packs with a large number of individual cells, there is a high requirement for consistency in the internal resistance of the batteries and devices during assembly. However, MHP-TA, due to its internal bimetallic structure, has excellent consistency in device resistance, which can greatly meet the requirements for battery internal resistance.