Fabrication of graphene and its application as nanocomposite material for lithium ion batteries

As the man’s life has significantly impressed with electronic mobile devices recently, the electronic industries have strived to prepare smaller, thinner and lower weight products. The giant electronic companies, therefore, compete in developing more efficient hardware such as batteries used inside the small metallic or polymeric frame. One of the most important materials in the production lines is the lithium-based batteries which is so famous for its ability in recharging as many times as a user needs. However, this is not an indication of being long lasted, as many of the electronic devices are frequently being used for a long time. The performance, chemistry, safety and above all cost of the lithium ion batteries should be considered when the design of the compounds are at the top concern of the engineers. To increase the efficiency of the batteries a combination of graphene and nanomaterials is recently introduced and it has shown to have enormous technological effect in enhancing the durability of the batteries. However, due to its vast amount of properties, these materials can be thought of as preparing the cathode electrode in the lithium-ion battery. Graphene is a free-standing 2D crystal with one-atom thickness of carbon atom. Those carbon atoms are sp2-hybridized atoms arranged in six-membered rings in a honeycombed network which is also considered as the fundamental foundation for fullerenes, carbon nanotubes, and graphite [1]. As a kind of carbon materials, graphene has attracted increasing attention in a variety of fields because of its large specific surface area, good flexibility, superior chemical/thermal stability, and extraordinary electrical, and thermal, mechanical properties. With so many advantages, it is desirable to utilize the unique properties of graphene in composites through the incorporation with all kinds of functional materials [2–3]. One of the most important applications of graphene-based composites is electrode material for lithium ion batteries [4-6]. In this paper, the various approaches to 13th Annual Electrochemistry Seminar of Iran Materials and Energy Research Center (MERC), 22- 23 Nov, 2017 142 characterize graphene as a composite material and the process of preparing it for the lithium-ion batteries as well as their electrical properties are discussed. We used the hummer method for synthesis of graphene as it’s been discussed by prior literatures. The methods of compositing were different like sol-gel, mechanical mixing, deposition, spray drying and coating.