Innovative Graphene-Aluminium Composite Developed

4 May 2021

Tirupati Graphite plc ('Tirupati' or the 'Company')

Development of Ground-Breaking Graphene-Aluminium Composite

Tirupati Graphite plc, the fully integrated, revenue generating, specialist graphite producer and graphene and advanced materials developer, is pleased to announce that Tirupati Graphene and Mintech Research Centre ('TGMRC'), its graphene and technology development unit, has developed a ground-breaking graphene-aluminium composite (the 'Al-Gr Composite' or the 'Composite'), which exhibits significantly higher conductivity and strength properties over aluminium and comparable to copper.  The Company has now engaged with potential end users including a FTSE 100 company for its potential use replacing copper in thermal, power and propulsion systems, which provides significant advantages owing to reduced weight.

OVERVIEW

The Al-Gr Composite successfully combines graphene with aluminium resulting in enhanced thermal and electrical conductivity and improved mechanical properties retaining aluminium's light weight:

·    Micro-hardness increased >300% over aluminium, which is 50% higher than copper

·    Thermal conductivity increased to >200% over aluminium, which is better than copper values

·    Electrical conductivity increased to >150% over aluminium, which is >95% that of copper; the Company aims to increase this with further optimisation

·    The composite is almost free from oxidation and carbide forms of aluminium, a critical achievement breaking the key technological barrier in development of the Composite

Al-Gr Composite has the potential to be used across various electrical and thermal conductivity applications with its significant advantage of weight reduction - wires and cables in motors for electric vehicles, aerospace, space, and satellite technologies, among others.

·    Copper is generally the material of choice for an array of electrical and thermal conductivity applications owing to its superior conductivity and other properties, but it is circa 3.2 times denser (i.e. heavier) than aluminium and circa 5 times as expensive.

Working with various leading industrial end-users to conduct the next stage of product testing, trial development, and scale-up with commercialisation focused engagements.

·    Leading FTSE 100 engineering company exploring the Composite's potential use in power and propulsion systems to reduce weight and thereby reduce the carbon footprint and emissions from current technologies and processes. 

·    Next steps include manufacturing a few kilo grams of the Composite for extensive application and product specific tests, both internal and external, as well as to establish large scale, end-product manufacturing processes.

·    Further development work will be undertaken to alloy the Composite with other metal additives to improve specific application related properties for advanced applications in structural materials for space, aerospace and land and sea mobility.

Shishir Poddar, CEO of Tirupati Graphite, said, "The message is clear across the world: a dramatic change in how we live is needed to combat climate change.  As part of this, stimulating innovation of low-carbon technologies including the creation of better materials is fundamental.  This was highlighted in a recent Insight from McKinsey, which said that 'New materials could deliver order-of-magnitude improvements in emissions performance' and that 'graphene, a material consisting of a one-atom-thick layer of carbon, can make batteries and solar cells significantly more efficient.' 

"We are deeply engaged in some of these innovations, looking to create disruptive new age materials, as demonstrated by the development of this ground-breaking Al-Gr Composite.  We are delighted that this achievement has caught the attention of several major companies globally, including a world leading FTSE 100 engineering group, with whom we are now working with to further develop our Al-Gr Composite and explore commercialisation opportunities.

"We believe that this material has transformational potential and could be a key contributor to emissions reduction as it evolves. We will continue to update the market on our progress as we achieve further milestones in our efforts towards developing and commercialising the Composite and other advanced materials and their applications." 

DETAILS

Tirupati continues to advance its operations across its portfolio including TGMRC in India, which is focussed on manufacturing zero-chemical graphene, developing graphene-enhanced advanced materials and applications, and providing environmentally friendly technologies for the mineral processing industry.  

TGMRC has developed a graphene-aluminium composite ('Al-Gr Composite') that retains aluminium's key properties including its light weight, whilst adding properties from graphene including increased thermal conductivity, electrical conductivity, and improved mechanical properties; the properties that generally make copper a preferred material in electrical and thermal conductivity-based applications.  Notably, the Al-Gr Composite has shown superior thermal conductivity and >95% of copper's electrical conductivity to date, which the Company anticipates can be increased with further optimisation of the material.

Aluminium and copper are the two primary metals used in thermal and electrical applications. Aluminium as a material is light weight, is corrosion resistant, has good formability making it easy to shape and mould, is highly recyclable, and is largely available. Copper is, however, often the material of choice for an array of electrical and thermal conductivity applications, generally owing to its superior conductivity properties over aluminium.  However, copper is circa 3.2 times heavier (higher density) than aluminium and over circa 5 times as expensive ordinarily.

The Al-Gr Composite developed by TGMRC, with its high conductivity properties and improved mechanical strength, has strong potential to substitute or displace the use of copper across various high-tech, weight sensitive, electrical and thermal conductivity applications, including in wires and cables in motors for electric vehicles, aerospace, space and satellite technologies, and in heat exchangers, heat sinks and similar thermal conductivity applications such as solar water heaters.

Importantly, the proprietary manufacturing process which has been developed by Tirupati is commercially scalable, tested and has already been used to manufacture batches of over two hundred grams of the pioneering Al-Gr Composite. The table below depicts the best achieved results obtained during the optimisation phase as measured by TGMRC:

Significant achievements and material properties of the Al-Gr Composite are as follows:

Physical Properties

·    Micro-hardness increased >300% over aluminium, which is 50% higher than copper

·    Thermal conductivity increased to >200% over aluminium, which is better than copper values

·    Electrical conductivity increased to >150% over aluminium, which is >95% of that of copper; the Company aims to increase this with further optimisation of the Composite

Structural Properties

·    XRD (X-Ray Diffraction used for identification of crystalline materials and analysis of unit cell dimension), along with micro-Raman (which uses a laser light to enable the analysis of very small regions) and TEM (Transmission Electron Microscopy) studies have confirmed composite formation between aluminium and graphene.

·    The Composite was found almost free from oxidation and carbide forms of aluminium, which is a critical achievement and is viewed as a technological breakthrough for R&D on similar composite materials.

·    The density of the Al-Gr Composite was found to be higher than of pure aluminium, suggesting that the graphene particles may have occupied intra-molecular spaces in the aluminium lattice, a significant indicator of the bonding of the two materials in the composite.

Interpreting the differentiating causes of these significant improvements

·    Tirupati's Reduced Graphene Oxide ('rGO') is produced with a zero-chemical process, hence has minimal heteroatomic contamination leading to better compatibility and surface interaction with other material matrices like metals, polymers etc.

·    Tirupati's rGO has a very high BET ('Brunauer-Emmett-Teller') surface area, which may have led to better dispersion and impregnation in intramolecular spaces.

·    Homogenous composite is formed, with Tirupati's rGO uniformly distributed throughout the volume of the composite, a depiction of the perfection of process developed.

Metal Matrix Composites ('MMC') with graphene have extensive prospects for and a wide range of possible technological applications based on their physical, electrical, mechanical, and thermal properties. Factors such as weight percentage, volume fraction, size, shape, and orientation can have a significant impact on the nature of the final composite material and its usefulness/effectiveness in various application arenas. The successful development of the Al-Gr Composite opens the doors for the Company to work on other forms of advanced and MMC materials as well.

The Next Steps

The Company is working with various leading industrial end users to conduct the next stage of product testing, trial development, scale up and commercialisation focused engagements.  These include a leading FTSE 100 engineering company, which is exploring the Composite's potential use in power and propulsion systems to reduce weight and thereby reduce the carbon footprint and emissions. As it looks to enlarge its sphere of engagement across segments of possible applications, the Company is also advancing engagements with other end-users. 

Accordingly, the Company will be manufacturing a few kilo grams of the Composite for extensive application and product specific tests as well as detailed studies to establish large scale, end-product manufacturing processes such as for moulding, extrusion, wire drawing and polymer coating for wires and cables.

Additionally, further optimisation work will be undertaken as well as work to alloy the Composite with other metal additives to improve specific application related properties for advanced applications in structural materials for space, aerospace and land and sea mobility.

Earlier in the year (see RNS dated 20 January 2021), the Company announced that it had further optimised the material properties of its zero-chemical graphene products to consistently achieve a specific surface area of 1100 - 1200 m²/g from 400 - 500 m²/g, demonstrating new standards of quality for its graphene.

This announcement contains inside information for the purposes of Article 7 of EU Regulation 596/2014. Upon the publication of this announcement, this inside information is now considered to be in the public domain.

** ENDS **

For further information, please visit https://www.tirupatigraphite.co.uk/ or contact:

Notes

Tirupati Graphite Plc is a revenue-generating, multi-asset, multi-jurisdictional, fully integrated producer and developer of high-grade natural flake graphite, speciality graphite and graphene and graphene enhanced advanced materials.  With a unique set of properties, graphite has diverse applications with multiple growth streams and graphene forms the new generation of 2D and advanced materials. The Company places a special emphasis on "green" applications, including renewable energy and energy efficiency, energy storage, thermal management and advanced materials development, and is committed to ensuring its operations are sustainable as well.

The Company's operations include primary mining and processing in Madagascar, where the Company operates two key projects, Sahamamy and Vatomina; 3,000 tpa of high-quality flake graphite concentrate with up to 96% purity is currently being produced and sold to customers globally, additional 9,000 tpa capacity expected to be commissioned in Q2 2021, and this is planned to increase to 84,000 tpa by 2024 as per the Company's modular medium-term development plan.

In India, through Tirupati Speciality Graphite Private Limited ('TSG'), with whom the Company has a binding acquisition agreement subject to regulatory approvals, Tirupati is developing a suite of speciality graphite for use in hi-tech applications like lithium-ion batteries, fire retardants, thermal management and composites. Its current operations include the 1,200 tpa Patalganga Project, which was commissioned in July 2019 to manufacture and sell CARBOFLAMEX®, a trademarked fire-retardant expandable graphite product. TSG is further developing 30,000 tpa specialty graphite project in two equal size modules and has developed unique green processing technologies for manufacturing these advanced materials.

TSG has also established and continues to develop the Tirupati Graphene and Mintech Research Centre, a state-of-the-art R&D centre focussed on manufacturing graphene, developing its applications and advanced materials using graphene, and further providing environmentally friendly technologies consultancy for mineral processing.