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Enhanced Energy Efficiency and Comfort by Smart Light Transmittance Control

Final Report Summary - EELICON (Enhanced Energy Efficiency and Comfort by Smart Light Transmittance Control)

Executive Summary:
Electrochromism is the phenomenon whereby a reversible colour change takes place upon redox reactions on passage of electrical current after the application of an appropriate voltage. The proposed SME-targeted collaborative project EELICON is concerned with an innovative switchable light transmittance technology based on electrochromic materials previously developed in projects co-funded by the EU Framework Programmes. The core of this development is a conductive polymer nanocomposite coating with outstanding electro-optical properties that can change its optical absorption properties within seconds with a high optical contrast. In liaison with compatible counter electrodes and polymer electrolytes, the material is well suited for the high-throughput production of mechanically flexible and light-weight electrochromic (EC) film devices with low energy consumption and fast response, opening the possibility to retrofit existing windows with a dimmable plastic film.
As it was revealed by life cycle assessment (LCA) studies the new EC technology – due to its inherently low embodied primary energy – is environmentally friendly and can result in considerable energy savings when attached to or included in appliance doors, aircraft cabin windows, and automotive sunroofs (key applications). As opposed to state-of-the-art liquid crystal films, EC films maintain their transparency throughout the switching process. This unique property profile was recently considered a breakthrough in overcoming common limitations of state-of-the-art smart window technology – the devices can be used in a multitude of applications where the control of visible light transmittance is required for reasons of safety, comfort and energy saving.

The development had been driven to the pilot-line production stage, the underlying nanotechnology-based processes largely understood, and corresponding intellectual property had been protected in European patents and patent applications. However, the decisive step from research to innovation, i.e. the use of the newly developed materials and materials technologies by the industry could not yet be accomplished. The development had hence arrived at the so-called Valley-of-Death for the following reasons:
- Process automation was strongly required.
- Scattered laboratory sites hampered the progress.
- No suitable producer could be identified.
- A high technical risk was associated with the multi-nanolayer technology pursued.
- Small sale numbers were anticipated for the initial market introduction period.
- Other more speculative reasons (undercapitalisation, lack of suitable human resources, etc.).

EELICON was supposed to tackle these drawbacks by overcoming equipment limitations, using process automation, and establishing a high-throughput prototype production for flexible and retrofit-enabling light modulation films in Europe. This ambitious task has been approached by:
- joining efforts of European and overseas players
- to integrate nanotechnology, materials, and production know-how.
- and utilisation of cost-effective processing options (cost target 200 €/m2)

The development has been driven by the integration of specific expertise of six European SMEs.
Project Context and Objectives:
EELICON is concerned with an innovative switchable light transmittance technology, the core of which are mechanically flexible and lightweight electrochromic (EC) film devices. These are based on a novel combination of EC and electrolyte materials creating a unique property profile far beyond the current state-of-the art, opening the possibility to retrofit existing windows with an electrically dimmable plastic film. According to life cycle assessment studies, considerable energy savings may result when such films are included in appliance doors, automotive sunroofs, and architectural glazing, and the comfort is significantly enhanced.

Although the development has been driven to the pilot-line stage, the decisive step from research to innovation has not yet been accomplished for a number of technical and economic reasons. To overcome this gap, EELICON is tackling existing drawbacks by removing equipment limitations and automating processes, thereby establishing a high-throughput prototype production for a cost-effective EC film technology in Europe (cost target 200 €/m2). The project comprises twelve inter-linked work packages (WP), nine of which were relevant in the final period.

The project spans pilot-line, validation, and prototyping phases (incl. business planning). The scientific and technical objectives including all management and market-oriented activities were planned to be accomplished in these three development steps:

- Pilot-line phase – develop existing IP covered results (months 1-12) -

Setting up modular a roll-to-roll coating and lamination pilot line with a working width of 500 mm including process validation. Running in organic synthesis pilot plant for precursor production.

Development of process automation technology for edge preparation, cutting, bus bar printing, and sealing, supposed to be accomplished as far as possible by robotics.

Preparation of 1st generation EELICON devices (technical benchmarking), including:
- Use of IP covered research results to produce device electrodes (half-cells) and full devices.
- Use of R&D centre and dry room facilities.
- Employment of economically viable and environmentally friendly industrial coating processes.
- Feedback loops from technical benchmarking (results from application testing).

Preliminary life cycle costing (LCC) and comprehensive market evaluation.

Technical accomplishments: optical homogeneity below visual perception level, response times, power consumption, and cycle-life according to individual requirement specifications.

Launch of a project website.

Literature studies.

- Validation phase, up-scaling and system integration (months 13-24) -

Preparation of 2nd generation EELICON devices, including:
- Integration of the process automation technology developed.
- Technology validation by extensive application and environmental testing. Evaluation of the influence of moisture and dust levels on the electro-optical performance and cycle-life.
- In-line quality control tool development.
- Optical contrast enhancement to comply with aircraft and automotive requirements (< 10 % transmittance in darkened state). Further development of associated metrology and standardisation.
- Development of a comprehensive protection concept: Exploration and evaluation of edge and areal sealing options to prevent moisture and oxygen contamination; Employment of UV protecting layers and/or additives to fulfil individual light stability requirements. Protection needs will strongly depend on the respective situation or location in the system.

System integration and microelectronic control according to the respective target applications, incl.:
- Equipment of test units or vehicles for key applications → racing car sunshades, electric car sunroofs and smart windows for vehicles, switchable domestic appliance doors.
- Application and field testing.
- Long-term cycling under ambient conditions (target cycle life of the devices: 10exp5 cycles, thermal operation range -25 to 80 °C).
- Response time towards 30-60 s for target size (Tier 2).

Midterm assessment: critical progress review, careful evaluation of results. Midterm milestone: Demonstration of successful process automation and bus bar printing/deposition.

- Prototype and evaluation phase (months 25-42) -

Technology transfer between partners – bringing the process steps to the prototyping stage → development of prototypes, using patent-pending technologies. Targeted level of moisture <20 ppm H2O.

Preparation of prototypes, including:
-3rd (final) generation fully operative dimmable EC film demonstrators 50 x 100 cm2 in size.
- Meeting essential market and consumer requirements for the targeted key applications in terms of colour, colouration depth, cycle life, operating temperature range, response time, and durability (comprehensive characterisation included).
- Life cycle assessment (LCA) and costing (LCC) according to ISO 14040ff to confirm energy saving potential and cost-effectiveness of the technology. Work out unique selling points for future producers.
- Prototype sampling to potential customers and end users

Exploration of potential use for applications with highly demanding size and stability requirements, but larger energy saving potential (e.g. architecture, glass façades, buildings).

Investigate whether the low cost target of the production flow can be obtained, including material supply chain, etc.

Exploration of economic perspectives and potential for growth and jobs, including a detailed market and competitor analysis.

Regulatory survey specific for electrochromic windows.

SME scouting

Business planning and business case development with the SMEs involved, including:
- Preparation of technical scenarios to help create new business opportunities and improve products and production;
- Scouting for additional IP in case of missing pieces of knowledge → search for EU patents on technical aspects necessary for the achievement of the project objectives.
Project Results:
Generally, a large amount of work has been performed for application and environmental testing and huge progress made in overcoming problems ‘from lab to fab’. One focus was laid on determining the durability of EELICON devices under different conditions and application scenarios (end-user evaluation). The technology shows remarkable robustness. In thermal load and thermal cycling application tests real degradation was observed not below temperatures of 75 °C. Transmittance levels and memory (‘drift’) are particularly favorable. Outdoor exposure (of double glazed units featuring the EELICON film) resulted in a gradual loss in mobile charge that is anticipated to be self-healing by intermittent resting periods or electrical rejuvenating measures. The current property profile qualifies the EELICON film for use as switchable sunroof and window retrofits, even at sub-zero temperatures.

The deliverable reports D7.1 - Moisture & oxygen protection concept and D7.3 -Technology with optimized response and contrast describe effective approaches to stabilize and optimize the technology with regard to different application scenarios. Work performed on the optimization of polymerization conditions has opened the way to a promising spin-off result: The creation of stable dispersions rather than monomer solutions to be polymerized by the tricky and multi-step approach of chemical oxidative in-situ polymerization.

The transfer of the IPR-protected knowledge behind the EELICON technology into prototype production and, hence, process loop closure was finally successful. Considerable progress was made in overcoming batch processing, establishing an inert R2R lamination module, and operating it to yield semi-finished, fully R2R-processed laminates of the target size (500 x 1000 mm2) supposed to be integrated into full prototypes for end user evaluation. This also comprised the production of large batches of chemical precursors as well as pre-contacted webs and electrochromic electrode roll material. The work performed is reported to large parts in three interrelated deliverable reports, i.e. D9.1 – Technology transfer accomplished, D9.2 - Prototype production established, D9.3 - Back-end assembly accomplished.

The strategic approach chosen (Convergent Synthesis Approach) and the modular Click&Coat™ equipment used enabled the consortium to optimize each process individually for high web speeds and high yields to approach market cost targets.

The converging technology transfer efforts also enabled the consideration of prototype designs for applications other than smart windows. EELICON’s high contrast EC films are appropriate to develop visual indicators to be in integrated in smart objects/smart labels for applications in the field of IoT, packaging or distributed healthcare. The automation of bus bar deposition by printing techniques offers substantial cost saving potential and the possibility to create devices with free-form geometries interesting for applications such as motorsport visors, complex-shaped windows or printed displays.

Life cycle assessment and costing results are described in the Deliverable reports D10.2 – RoHS compliance report, D10.3 – LCC report and D10.4 – Recycling concept. Excellent progress has been made towards updating the most important impact factors of manufacturing EC windows based on EELICON technology, including costing and recycling considerations. The results are generally looked upon and interpreted from different application scenarios and provide a sound basis for future development activities. From condensing all technical information, a permanent mobile application in a warm location will have the highest competitiveness and sustainability potential.
Regarding dissemination, exploitation and scouting focus was laid on elaborating on business plan recommendations accompanied by the evaluation of talks with external interested parties that could profit from the EELICON solution. Needs analysis, interviews and business planning considerations are described in Deliverable reports D11.4 - Needs assessment accomplished, D11.7 - Business plans and D12.4 - Business plan recommendations.

Substantial efforts have been made in understanding and describing the market situation and needs. A TRL of 5-6 has been confirmed. Concerning the project’s target prototype unit production costs of 200 €/m2, a preliminary business case study performed yielded a total cost of goods sold (CoGS) for the first year of production of around 1.1 M€ with a 334 €/m², expected to drop to over four-fold to 78 €/m² by year 6.
Potential Impact:
It is expected that the EELICON technology can be developed to address the main market needs and comply with price constraints and customer requirement specifications. Relevant IP is available for exploitation. The project fully complies with the objectives of NMP Activity 4.4 – Integration and call NMP.2013.4.0-3 - From research to innovation: Previously obtained research results are used by industry, the European paradox is relieved, and the valley of death is overcome by following three pillars of development. The project is characterized by strong industrial/SME participation. Eight out of 13 partners are industrials, six of which being SMEs with leading roles, which is an excellent pre-requisite to achieve the set goals.
Due to the huge potential market size and (already existing) high demand for self-tinting solutions on these markets, it makes sense to focus on architectural and automotive applications. Critical technical requirements here are lifetime, transition times between transmittance levels and (partially) color tone. Those have to be focused on and may need to be improved for a successful market entry.
Finding a partner or client with the financial muscles and tenure to push the EELICON technology is key, as it may require a novel manufacturing setup and following investments. Ideally, this will be a production partner with know-how in both plastic film and glazing such as Tier 1 or Tier 2 suppliers to vehicle manufacturers. Unit cost (m2 of EELICON film) is the most important non-technical factor, though considered less important with regard to premium applications such as luxury vehicles. Time is of essence as the dimmable window market is changing fast.

To enable future success of the EELICON solution, the definition of value chain set-ups is highly relevant and a factor of competitive advantage. Once the right partners for production and distribution are found a tremendous potential impact can be identifed.

The successful innovation will create new businesses for flexible EC films and windows in Europe. Besides, uses for EELICON films beyond the primary smart windows markets in existing consumer application customer markets were identified. The need for color changing films is growing thanks in part to several “smart product” developments within consumer goods companies, plus through the need for natural human interfaces in ambient intelligence related developments. The new production is therefore explicitly not meant to replace existing ones, but to generally increase the level of employment in EC technology business and complement the existing portfolio by a low-cost flexible EC product.
List of Websites:

Contact: Dr. Uwe Posset,
Expert Group Manager Electrochromic Systems
Fraunhofer R&D Center for Electromobility (FZEB)
Phone +49-(0)931-4100-638, Fax -570
Fraunhofer ISC
Neunerplatz 2, D-97082 Wuerzburg, Germany