Why graphene battery has become the most concerned battery?

What is the latest development of graphene batteries? Graphene batteries have been attracting attention from users since they were invented, and they are important and popular batteries for future mobile phone batteries and new energy electric vehicles. However, graphene batteries have recently cooled down. What kind of things? The following are the latest developments in graphene batteries. Graphene battery 1. Why graphene battery has become the most concerned battery (1) Combining the advantages of lithium batteries and supercapacitors, it has the characteristics of high power density and high energy storage density. The energy density is 160 watts/kg, and the power density is 100 kilowatts/kg. (2) The theoretical capacity of a single-layer graphite material is more than twice that of graphite (ie >744mAh/g). (3) Each carbon atom in graphene is sp2 hybridized, contributing a remaining p orbital electron to form a large bond. Electrons can move freely, so that graphene has good conductivity. (4) Electrons are not easily dispersed when transported in graphene, and their mobility is as high as 200,000 cm2/(V*s), which is about 140 times that of electrons in silicon. Its electrical conductivity is as high as 104S/m, which is the best electrical conductivity material at room temperature. (5) Through chemical modification, the conductivity of graphene can be controlled, and various graphene-based derivatives can be obtained at the same time. (6) Under certain conditions, double-layer graphene also has insulating properties. Graphene is the strongest and hardest crystal structure of all known materials. Its tensile strength and elastic modulus are 125GPa and 1.1tpa respectively. The strength limit of graphene is 42N/m2. (7) The room temperature thermal conductivity of graphene is about 5300W/m-k, which is higher than carbon nanotubes and diamond, and is more than 10 times the room temperature thermal conductivity of copper. The theoretical specific surface area of u200bu200bgraphene can reach 2630m2/g. 2. Reasons for outgassing of graphene batteries (1) Recent studies have found that if humans accidentally ingest graphene, it can penetrate human cells and destroy the substances in them. In other words, it may be toxic. (2) The price of traditional conductive carbon/graphite is low and sold per ton, while the price of graphene is too high. The price of one kilogram is not something that ordinary companies can afford. A few years ago, the price of graphene was as high as 5,000 yuan per gram, much higher than the price of gold, and ordinary consumers could not afford it. 3. What is the development direction of graphene batteries. The development of graphene preparation technology (1) The preparation of graphene microspheres In 1859, Brody prepared a graphene oxide solution, that is, graphene acid at that time. In 1958, Hummers developed this method, and it is now an important method for the chemical preparation of graphene. Other methods: such as micro-mechanical dissolution method, chemical synthesis method, etc. (2) Preparation of large-area graphene film In 2006, Berger et al. rearranged graphene for the first time by heating silicon carbide to exude carbon atoms (0001). In 2008, Coraux et al. used C and Ha as raw materials to prepare graphene on the surface of Ir(111) by CVD. In 2009, Kim et al. used C and Ha as raw materials to epitaxially grow graphene on the Ni(111) surface. In 2012, Cheng Huiming, Ren Wencai and others prepared hexagonal single crystal graphene of about 1mm2 on precious metals, which achieved lossless transfer. Other methods: Graphene, such as electrostatic self-assembly method and spin-coating method, is widely used in lithium batteries as an active material with excellent performance, but it is only a matter of time. The key to the application of graphene in lithium batteries is how to reduce the cost of graphene. The unresolved theoretical problem is the interaction of graphene with electrolyte and electrode materials. What can be concerned is the composite process of graphene and cathode material, how to improve the uniformity and adsorption performance of the composite material. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: What is the important difference between polymer batteries and lithium batteries?