Lighter, Cheaper Thermoplastic CNG Tanks for Automotive & Commercial Vehicle Markets

Project Information

Polaris

Grant agreement ID: 820567

DOI 10.3030/820567

Closed project

EC signature date 4 July 2018

Start date 1 August 2018

End date 31 October 2020

Funded under

• Horizon 2020 Framework Programme

Total cost € 2 481 062,50

EU contribution € 1 736 743,75

Coordinated by

NETCOMPOSITES LIMITED
United Kingdom

Periodic Reporting for period 2 - Polaris (Lighter, Cheaper Thermoplastic CNG Tanks for Automotive & Commercial Vehicle Markets)

Reporting period: 2019-08-01 to 2020-10-31

Summary of the context and overall objectives of the project

Problem/issue being addressed
CNG (Compressed Natural Gas) tanks are used in 1.3 million vehicles in Europe (24 million worldwide) and are typically made from a metal or polymer liner, over-wound with a carbon/epoxy thermoset composite. However, carbon/epoxy composites are not ideal. This wet winding process results in inconsistencies in the epoxy matrix and misalignment of the carbon fibre, giving up to 10% variation in tank burst pressure. More material is therefore added to compensate, increasing cost and weight, and the process is slow.
One alternative is to manufacture carbon/polyamide thermoplastic tapes, and subsequently heat and apply them to the liner in a high-speed winding process. This process has the potential to overcome the variation in wet-wound epoxies, but material manufacturers have not previously been able to make tapes of high enough quality, and vessel manufacturers have not been able to wind them efficiently.
To overcome this problem, Coventive Composites has developed an improved impregnation process to make carbon/polyamide tape with lower voids and less variability in performance. In parallel, MFTech has developed a robotic winding process to double production speed, so that Plastic Omnium can efficiently manufacture CNG tanks with carbon/polyamide thermoplastic tapes.
This new thermoplastic tape, robotic equipment and winding process allows the production of higher quality pressure vessels, reducing variation in tank burst pressure. This enables less material to be used, saving both cost and weight. Plastic Omnium’s testing has shown that these pressure vessels can meet (and exceed) the targets set by their customers, reducing weight by 10% and reducing cost by 20%.

Why is it important for society?
By developing a new generation of CNG tanks, this project supports the aim of the European Alternative Fuels Strategy:
• Reduce oil dependence
• Reduce GHG emissions
• Improve the air quality
• Enhance the competitiveness of European industry
The strategy document established a coherent policy on alternative fuels. CNG forms an integral part of this strategy.

Overall objectives
The tape, winding process and pressure vessels have so far been demonstrated on a prototype scale, and the specific objectives of this project address 3 key barriers to commercialisation:
• Optimise and upscale the tape process to meet cost, processability and property requirements.
• Enhance the vessel-winding process to meet performance, weight and productivity needs.
• Upscale the manufacture of carbon/polyamide CNG tanks, to enable economic production.
This project will advance the development to TRL 8, meeting customers’ cost and weight targets.

Conclusion of the action
By the end of the final period, the key results can be summarised as follows:

1. Refined formulations of the thermoplastic tapes, which have been validated through the production and testing of CNG tanks manufactured by MFTech and tested by Plastic Omnium.

2. The development and implementation of an upscaled tape production process by Coventive Composites that is capable of manufacturing the PA6-carbon fibre tapes with the required quality and production volumes to support post-project exploitation.

3. The development and implementation of an upscaled CNG tank production process by MFTech, which is capable of manufacturing the thermoplastic tanks at the required rate and quality to meet the commercial requirements of Plastic Omnium.

4. The preparation of a robust business plan to support the post-project commercialisation needs of the project partners.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

From the outset, the programme of work was underpinned by a commercialisation plan in order to provide a strong market and customer focus for the research and development activity. This plan encompassed a broad range of aspects including market intelligence, the supply chain, sales and marketing strategies and distribution/logistics. It had a significant ongoing input into the development of the thermoplastic tapes, their method of manufacturing, and the manufacture of the tanks and their testing.

Based on the findings of the commercialisation plan, a range of tape formulations were tested and refined with a view to meeting customers’ requirements. By the end of the project, a preferred formulation had been identified and has now been standardised within Coventive Composites’ own internal New Product Development procedure.

Having optimised the tape formulation and its method of impregnation, the next step was to implement a modified upscaled process for producing tapes of the required specification, quality and volumes. Each aspect of the production process was examined and refined. This included improved approaches to material handling, control of polymer content, polymer impregnation strategy, online quality control and product presentation/packaging.

Investigations took place to refine the best way to lay the tapes and the equipment requirements for this operation. The process was simulated by Plastic Omnium to provide the optimum laying strategy and various heating sources were evaluated. By the end of the project MFTech had produced a machine capable of manufacturing CNG tanks at the required rate and quality.

Finally, in order to demonstrate and validate the performance of the CNG tanks, MFTech manufactured tanks for Plastic Omnium to evaluate to ISO standard 11439. These tanks were extensively evaluated by Plastic Omnium and they were able to report that the tanks passed the tests performed.

Furthermore, a robust costing model developed by Plastic Omnium has demonstrated that the thermoplastic approach is cost-competitive with the tanks currently made via the thermoset route.


With regard to the protection of the knowledge generated within the project the main focus has been to follow the “trade secrets” route. However, a couple of patents were applied for in relation to the tapes being developed by Coventive Composites.

Due to the impact of COVID-19, the process of meeting potential customers and our generic approach to them in order to elicit their feedback had to change. The release of non-confidential information through traditional channels such as trade presentations, workshops, exhibitions and fairs was significantly impacted by COVID-19 during 2020. Although involvement in some virtual events was possible, the majority of this work was done via “one-to-one” web meetings. The partners’ dissemination activities within the project have been closely focused on business-to-business interactions, primarily via “one-to-one” web meetings due to the impact of Covid-19. The aim has been to build the future sales pipeline to support post-project commercial exploitation activities.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The results achieved are all in line with the expected impacts for the project. Specifically, the materials and processes developed will enable Plastic Omnium to have CNG tanks fit for purpose. With these changes they will improve their economic (cheaper processing), environmental (lighter parts) and social (safer working practices with less solvents) performance as part of a business improvement.

These new materials are also highly relevant to a number of other markets and applications where fibre reinforced thermoplastic tapes can replace thermosets and metals, including rail, maritime, offshore and construction.

Carbon fibre polymer tape

Extract of tape manufacturing line at Coventive

Plastic Omnium - tanks for testing

Tank manufacturing line at MFTech