A specialist manufactuer has been able to invest in new production capabilities thanks to support from AMRC engineers, as part of a research collaboration project. 

Kent-based H V Wooding, which specialises in precision engineered metal components for the automotive and aerospace sectors, worked with a team at Factory 2050, based at the University of Sheffield’s Advanced Manufacturing Research Centre (AMRC), alongside materials and engineering researchers from the Nuclear AMRC and other parts of the University to improve the quality of its busbars.

Busbars are insulated metal strips which carry high-current power between different parts of an electrical system and are a critical component in electrification, particularly in the battery packs for electric vehicles. Increasing operating voltages offers performance increase, but places greater emphasis on the integrity and reliability of the insulating coating applied to the busbar.

The project, supported by Innovate UK through the Faraday Battery Challenge, aimed to develop a new powder coating process to improve the quality and performance of busbars for the fast-growing electric vehicle market.

Discussing the part the AMRC team played in the project, technical fellow, Lloyd Tinker said: “The team at the University of Sheffield, led by the team at the Nuclear AMRC supported H V Wooding in developing and validating new processes for coating busbars via fluidised powder bed and spray coating. 

“The AMRC team at Factory 2050 generated concepts to implement these coating processes through flexible automation which could cope with the wide variety of components H V Wooding produces.”

Simon Stewart, technical manager at H V Wooding, commented: “We found that customers in the electric and hybrid vehicle market tended to specify their requirements in terms of kilovolt rating and insulation performance, not coating material or application method.

“The existing coating methods were difficult to control, causing a high level of component rejections due to the coating specification and application failing to meet requirements. Speaking with customers, it was clear that a new coating method was needed to produce busbars with a consistent specified performance.”

With the demand for busbars expected to increase significantly as road transport is electrified, an optimised and automated manufacturing process will give H V Wooding a significant competitive advantage in a rapidly expanding international market.

The project focused on epoxy powder coatings, applied by fluidised bed or spray processes. Powder coatings are generally safer than heat-shrink sleeved insulation and offer better thermal and electrical performance which allow for a more compact battery design.

The Nuclear AMRC researchers designed a series of experiments to be carried out at H V Wooding’s production facility, to determine and optimise the key process variables for a variety of coating processes. The researchers also worked with the company to optimise laser cutting and deburring of the metal busbar, as any surface burrs can affect the performance of the coating and define a standardised production process from stock material to final testing.

During the one-year project, the Nuclear AMRC team drew on additional expertise from the University of Sheffield. The AMRC – like the Nuclear AMRC, part of the UK’s High Value Manufacturing Catapult – advised on how the optimised process could be automated and scaled up, and the University’s department of electronic and electrical engineering helped develop a standardised test procedure for quality assurance.

“The results have allowed us to better understand the relationship between the dielectric strength of the busbar and the coating thickness produced by the processes investigated,” says Paul Allen, business development director at H V Wooding. 

“Even before the project finished, we secured new business as a result of the improved control of the busbar coating process. This contract has allowed us to invest in a nickel electroplating production line to enhance our production capacity and capability.”

James Leatherland, the Nuclear AMRC’s programme manager for collaborative R&D projects, said: “H V Wooding has been a great collaborative partner to work with. It’s great to see a project that has had immediate benefits for a UK manufacturer with business wins happening before the project has concluded. 

“We think this project and the investment in the automated manufacturing process will put H V Wooding into a globally competitive position in a growing and important market.”