Graphene is a two-dimensional material, that is to say made of a single layer of atom. Stacking these layers gives graphite, one of the natural forms of carbon. Synthesized in 2004 at the University of Manchester (it earned its “discoverers” the Nobel Prize in physics in 2010), it has long been considered a physical anomaly, a 2D material is supposed to be unstable.
Graphene has unusual properties:
Equipped with the same principle of construction as carbon, which one of the natural forms is the diamond, it is extremely solid . From graphene, MIT researchers have succeeded in creating a 3D assembly ten times stronger than steel, but as light as plastic.
Composed of a single layer of atom, it is also extremely light . This property offers particularly interesting prospects in the field of aeronautics, where the weight of embedded elements has a direct impact on energy consumption.
It is an excellent thermal conductor , with a transmission rate 30 times higher than silicon, a material previously used the most in the electronics industry.
It is perfectly waterproof and allows to consider new uses combined with its conductive properties in humid environments.
It is deformable and transparent , and could probably give rise to a new generation of flexible screens – although the first versions of flexible screens marketed still use plastic – and to new generations of transparent screens, exploitable in particular in the field of the automobile
Almost 15 years after its first synthesis, it finds relatively few applications in our daily lives. The processes of synthesis of graphene on an industrial scale are not yet sufficiently profitable not satisfactory, some mechanical exfoliation too deteriorating the mechanical properties of the material to legitimize its use compared to other materials already well mastered, as silicon.
In 2018, the European Commission has launched the largest research program ever carried out in Europe, injecting 1 billion euros of budget over the next 10 years. Objective: to create a Graphene Valley that supports the growth of industrial uses of graphene, with the key to a significant economic windfall.
Applications in the energy field
The applications of graphene are numerous in the field of energy, taking advantage of the conductive properties of the material.
In a sector that affects us daily, we mentioned the announcement of the manufacturer Huawei who introduced the first mobile phone equipped with a graphene-based cooling system that allows to conduct heat in an evaporation chamber with the largest efficiency, and thus less stress components to improve their service life.
The start-up Earthdas is working on lithium batteries whose anodes contain graphene and can accelerate the speed of loads in huge proportions. We are talking about a recharge 12 times faster compared to a conventional lithium-ion battery and a complete charge in minutes for a phone.
The addition of graphene to lithium-ion batteries, replacing silicon, is also expected to extend battery life thanks to graphene’s resistance to temperature variations. In the case of applications related to lithium-ion batteries, graphene therefore essentially reinforces the capabilities of a traditional battery to increase performance and longevity.
You can already find a model of external graphene batteries at Execujet, which offers a model of 6000 mAh with a charging time of 20 minutes.
The ultracapacitors (or “super capacitors”) are also the subject of research to improve their life and drastically reduce their load times. Unlike conventional batteries that produce energy through a chemical reaction, supercapacitors store energy in the form of an electrostatic field. A conventional supercapacitor charges (and discharges) much faster than a battery, but stores much less energy.
The use of graphene could make it possible to combine the speed of loading of supercondos with a much larger storage capacity. The French company Nawa Technologies is working on supercapacitors made of carbon nanotubes – rolled graphene sheets – which will ultimately allow cleaner energy (no chemical components) and more sustainable, especially in the transport sector. The company is already testing the electric racing cars of the Formula E Championship to test these products in extreme conditions.