Donaldson, the international filtration company, has extended its range of battery venting systems with the Dual-Stage Jet, a design that improves EV safety by offering what the firm says is “the industry’s fastest degassing capabilities, while streamlining the installation process for OEMs.”
Fast degassing of a EV battery pack if it goes into thermal runaway is important, preventing the risk of explosion. For every 1kWh of battery capacity, approximately 700 litres of gases are released. With some newer EV models coming to the market with up to 100 kWh batteries, it’s important to understand the potential hazards. Strictly speaking an EV explosion is actually a VCE (a vapour cloud explosion). The gases released are toxic and flammable.
Donaldson’s new product was launched at The Battery Show in Stuttgart, Germany this week.
The DSJ provides pressure equalization and ingress protection under normal operating conditions with a minimum airflow of 97 lit/hr @ 10 mbar. But it can allow gases to escape at rates of approximately 100 lit/sec @ 100 mbar when necessary.
“Customers need even higher degassing rates so we came up with a creative design where the poppet and cap can be jettisoned to instantly produce a much larger opening for gas to escape and help mitigate thermal runaway,” Shane Campbell, product manager for vehicle electrification at Donaldson, told Batteries International.
“The pressure then rapidly decreases inside the pack, greatly reducing the risk of damage to additional cells and giving occupants extra time to escape from the vehicle.
“Another major benefit is that these high-performance vents can reduce the number required on a battery pack by 50%-90%.”
Using Donaldson’s proprietary Tetratex expanded polytetrafluoroethylene (ePTFE) membranes for protection from contaminants, the DSJ enables consistent pressure equalization with a minimum airflow of 97 lit/hr @ 10 mbar during normal operation.
The hydrophobic membrane consists of small, randomly connected fibrils that create a permeable water barrier, providing continuous pressure equalisation, while offering IP67, IP68 and IP69K ingress protection against water, dirt, and other contaminants.
The membrane’s unique oleophobic treatment also helps the filter media repel oils, providing additional protection.
By ensuring that damp air, which could otherwise accumulate inside the battery housing, is expelled, the effective ventilation provided by the new vent helps to prevent potential internal condensation issues reducing the lifespan of enclosures and batteries alike.
