Donaldson – The science and technology behind venting for battery packs

One of the most critical components in modern electronic equipment, ranging from the horn through to the battery pack of an electric vehicle is the venting.

Well designed venting systems extend component and battery life cycles by providing protection against contaminants. For batteries, the venting system must also be capable of providing immediate pressure relief if the battery is subjected to thermal runaway.

Venting is also important on the production line of electric batteries and components. One of the global leaders in filtration technology is Donaldson, which exhibited its comprehensive range of clean air solutions specifically designed to meet and enhance the unique manufacturing requirements of electric and hybrid vehicle technologies at The Battery Show Europe in Stuttgart, Germany.

From the safe handling of explosive and hazardous dust to meeting the ISO 8573-1 standards for CO₂-free compressed air, Donaldson offers a diverse array of capabilities to cater to its customers’ needs.

Automotive Industries (AI) sat down with Paul Gossez – Global Application Engineering Director Vehicle Electrification & Medical Devices Life Sciences and Thibaut Quarre – Equipment Sales Manager Europe-Middle East-North Africa for Donaldson Industrial Air Filtration Torit DCE at The Battery Show Europe.

AI: What are the key considerations when it comes to battery vent design.

Gossez: There are many factors which need to be considered, but the main consideration is pressure equalization. The vent has to ensure that the pressure is continuously equalized between the internals of the battery pack and the environment to prevent pressure build-up in the pack. At the same time the vent must prevent ingress from outside contaminants, including dust, oil, and water.

We also have to consider emergency degassing in case of a thermal runaway event. In addition, we need to consider the full temperature range for the application in which the vent is expected to be used.

Those are the main factors. There are many others, which is why it is so important that we are consulted very early in the development process to allow our customers to really leverage our expertise in their designs. We help them to understand the exact functionality of the product and what it is able to do for them.

AI: What venting solutions were you showcasing at the Battery Show Europe?

Gossez: The company showcased four different products – our Dual-Stage Burst Battery Vent, with an optimized cap as well as the Dual-Stage Flex Battery Vent, designed to enhance the protection, lifespan, and reliability of automotive battery packs in electric and hybrid vehicles. We also showcased powertrain venting solutions for the electrical drive modules and ePTFE membranes for fuel cell applications.

AI: How does the Dual-Stage Flex Battery Vent enhance battery pack protection?

Gossez: Basically, the pressure equalization is provided by a high efficiency membrane which is placed within a vent to ensure continuous equalization of the pressure between the external environment and the internals of the battery pack.

The membrane is mounted on a specifically designed umbrella, which increases the outgoing air flow when it senses that pressure is building up in the pack due to a thermal runaway event. The same umbrella closes off when the internal pressure decreases, ensuring the battery pack if fully sealed again external contaminants.

AI: How can Donaldson Clean Air Solutions help safeguarding the quality and integrity of manufacturing operations?

Quarre: In addition to providing solutions for batteries when they are in operation, we need to consider the manufacturing stage. That is where Donaldson operates as well, by providing what we call “clean air”.

Each stage of the battery manufacturing process generates a set of contaminants, either particles or fumes – or both. Our specialty is that we understand the processes and can provide a solution to capture dust and other contaminants before they affect the purity of the battery cell and impact its lifetime.

So, we remove the contaminants. We filter the air to a very high level of purity to safeguard the integrity of the battery manufacturing process, as well as minimize the emissions that escape into the environment.

AI: What is unique about the manufacturing requirements of electric and hybrid vehicle technologies?

Quarre: Each stage of manufacturing emits a range of dust and particles, and the composition differs according to the technology. Firstly, there are different raw materials that are mixed together for the battery. Then, you weld and coat. Each operation generates some contaminant.

Specific solutions are required for each stage and the nature of the contaminant. Donaldson has a range of solutions for each step in the manufacturing process, going from a high dust load to very small particle filtration. The filtration systems can be adapted to minimize the risks from the dust and gases generated by the manufacturing processes.

Whether you need to protect workers’ health or deal with the risk of dust explosions, we have the solution in our product range.

AI: How do you address individual manufacturing challenges facing different OEMs?

Quarre: We start with our standard range of products and get to understand the customer application. For that we have a team of application engineers and a laboratory that can analyze the characteristics of the dust or contaminant. Using this information, we are able to design the right solution.

And we can deliver a full turnkey solution to the customer’s site. Once operational, we are able to maintain and service the system. So, we offer a  really comprehensive solution by integrating the design, installation, and servicing.

Maintenance is either scheduled through online monitoring of the system or through predictive scheduling that determines what maintenance needs to be done at which stage of the life of the system.

AI: What is next for Donaldson?

Gossez: The Battery Show Europe has highlighted how much is going on in the development of batteries. We will stay abreast of all the trends in manufacturing and technology to ensure that we can provide the best and most appropriate venting solutions for those new applications.

Quarre: Donaldson is a technology-driven company.  Today, the focus is on developing solutions that maintain long-term filtration performance by providing customers with solutions to monitor the system and schedule filtration system maintenance.

The aim is to provide effective filtration during production time without interruption or loss of efficiency.