Delo Adhesives Help the Auto Industry Keep It Together

A bevy of modern automotive components require crucial adhesives from Delo.

Dan Carney, Senior Editor

April 23, 2024

2 Min Read
How an LED light is bonded together.
How an LED light is bonded together.Delo

Bavarian commercial adhesives manufacturer Delo is successfully pressing its way into the automotive market with glues that are used in modern components such as electric vehicle battery packs and LED automotive lighting. Delo works with companies like Mercedes-Benz, Samsung, Bosch, and Foxconn in the auto industry.

Bosch uses the company’s Delo-Duopox TC8686 structural adhesive to glue 48-volt battery packs together for mild-hybrid vehicles.

An ordinary adhesive might work fine holding a battery pack together, but it could also insulate the battery cells from the housing, trapping heat inside the battery. Delo’s adhesive has a thermal conductivity of 1.0 W/(m·K), so it transfers battery cell heat to the housing, where it can be dissipated.

This lets Bosch simplify the production of its batteries by combining structural bonding and thermal management system mounting in one step instead of having to manually fix battery cells and then use gap fillers for heat dissipation. A degree of flexibility compensates for the different thermal expansion behaviors of cell and housing material during operation.

Delo says that it developed this product specifically for Bosch with industry-standard UL 94 V-0 flame retardance and tolerance of the battery’s wide temperature range of –40 °C to +180 °C. The company cites the adhesive’s tensile shear strength, which on aluminum is 18 N/mm². By optimizing it for manufacturing processes with good visibility to cameras, the adhesive is easy to for automated systems to detect. This lets Bosch apply the adhesive precisely for high quality assurance.

Related:Bonding Over Adhesives

In LED automotive lighting, Delo has developed Photobond OB4189 to be resistant to yellowing, as shown by life cycle simulations of 500 hours at 140 °C. The modified acrylate is solvent-free and developed for a temperature application range of -40 °C to +120 °C. It has a compressive shear strength of 30 MPa on polycarbonate and 25 MPa on PMMA.

delo_news_header_esc_48v_automotive_battery_system_01.jpg

It can be cured with UV light (365 nm) and visible light (400 nm). The typical exposure time at 400 nm with a layer thickness of 100 μm is 5 seconds. This enables high-precision active alignment processes for optical components and low cycle times in automated production.

Because of its high aspect ratio, this adhesive is particularly suitable for bonding microlens arrays, such as those found in LED headlights and projection systems.

Microlenses are often made of optically pure adhesive polymers to create microlens arrays fixed to a housing. Delo says that the adhesive retains its shape after dispensing and does not flow, which is important for bonding microlens arrays.

Related:Bosch Targets Fuel Cell Platinum for Recycling

About the Author

Dan Carney

Senior Editor, Design News

Dan’s coverage of the auto industry over three decades has taken him to the racetracks, automotive engineering centers, vehicle simulators, wind tunnels, and crash-test labs of the world.

A member of the North American Car, Truck, and Utility of the Year jury, Dan also contributes car reviews to Popular Science magazine, serves on the International Engine of the Year jury, and has judged the collegiate Formula SAE competition.

Dan is a winner of the International Motor Press Association's Ken Purdy Award for automotive writing, as well as the National Motorsports Press Association's award for magazine writing and the Washington Automotive Press Association's Golden Quill award.

AstonMartinVanquish_©AndyMorgan_025_copy_2.JPG

He has held a Sports Car Club of America racing license since 1991, is an SCCA National race winner, two-time SCCA Runoffs competitor in Formula F, and an Old Dominion Region Driver of the Year award winner. Co-drove a Ford Focus 1.0-liter EcoBoost to 16 Federation Internationale de l’Automobile-accredited world speed records over distances from just under 1km to over 4,104km at the CERAM test circuit in Mortefontaine, France.

He was also a longtime contributor to the Society of Automotive Engineers' Automotive Engineering International magazine.

He specializes in analyzing technical developments, particularly in the areas of motorsports, efficiency, and safety.

He has been published in The New York Times, NBC News, Motor Trend, Popular Mechanics, The Washington Post, Hagerty, AutoTrader.com, Maxim, RaceCar Engineering, AutoWeek, Virginia Living, and others.

Dan has authored books on the Honda S2000 and Dodge Viper sports cars and contributed automotive content to the consumer finance book, Fight For Your Money.

He is a member and past president of the Washington Automotive Press Association and is a member of the Society of Automotive Engineers

Sign up for Design News newsletters

You May Also Like