The Prädifa Technology Division of Parker Hannifin, the worldwide leader in the field of motion and control technology, has introduced CliPHvent, a new generation of vent valves for EV battery housings. In the event of pressure differences between the interior of a housing and the environment, as well as when sudden overpressure occurs inside a housing, CliPHvent ensures controlled pressure compensation or fast venting. This is particularly important in case of a thermal event in the traction batteries of electric vehicles.
Image Credit: Parker Hannifin
Protection Against Sudden Pressure Increase Caused by Overheating
A “thermal event” or “thermal runaway” describes the sudden and rapid heating of a single or several battery cells due to a defect such as mechanical damage, an electrical short circuit, or overload. Especially in the powerful batteries supplying the propulsion energy in electric vehicles, thermal runaway causes huge amounts of gas to form inside the housing, which leads to an uncontrolled and rapid rise in pressure and may have serious consequences up to and including the complete destruction of the traction battery and even the whole vehicle. CliPHvent vent valves from Parker Prädifa have been specifically developed to prevent that.
By enabling fast venting via the integrated seal, they protect the battery housing, resulting in higher safety for the traction battery. In the case of thermal runaway in a single battery cell, a domino effect, i.e., the spreading to adjacent cells followed by rapid propagation across the entire traction battery and its complete destruction, can be prevented.
Compensation of Minor Pressure Differences, Protection Against Ambient Influences, Easy Installation
Minor pressure differences between the interior of the housing and the environment due to air pressure or temperature changes are compensated via a membrane. In addition, Parker aspire® membranes are water- and oil-repellent. As a result, CliPHvent vent valves provide reliable protection against ingress of external liquids and dirt.
The special, compact design of CliPHvent vent valves enables easy snap installation without the use of tools, on the battery housing or inside a bore.