Application of graphene in lithium batteries

Graphene is a single layer of carbon atoms, a sheet-like continuous hexagonal two-dimensional material composed of sp2 hybrid orbitals. It is the world's thinnest, highest strength and hardness, almost completely transparent crystalline material known in the world. It only absorbs 2.3% of visible light, and its strength under ideal conditions is about 100 times that of ordinary steel. The thermal conductivity at room temperature is as high as 5300W/(m·K), which is equivalent to the upper limit of the thermal conductivity of carbon nanotubes of 5800W/(m·K), and its electron mobility at room temperature is above 15000cm2/(V·s), which is high Compared with ordinary carbon nanotubes and more than 10 times higher than silicon crystals, its resistivity is about 10-6Ω·m, which is lower than copper and silver. It is the smallest resistivity material in the world, and its theoretical specific surface area can reach 2630m2/g. Graphene's high electrical conductivity, thermal conductivity, low resistivity, high strength and hardness, as well as the double-sided open structure characteristics that can be easily synthesized with other materials, will hopefully greatly improve the performance of existing lithium-ion batteries. According to the research progress of many graphene lithium-ion batteries, it can be found that graphene has the potential to improve the performance of lithium-ion batteries. The composite of graphene and lithium ion battery cathode material can increase the specific surface area of u200bu200bthe electrode material, improve the conductivity, and increase the effective capacity of the material. Compounding with metal oxides can increase the conductivity of the material. Due to the structural characteristics of graphene itself, the volume expansion of metal oxides during charging and discharging can be avoided, thereby increasing the stability of the material and improving the charging and discharging life of the material. At this stage, the quality of graphene itself is difficult to achieve defect-free and 100% single-layer rate, resulting in the performance of graphene lithium-ion batteries that cannot reach the expected performance. However, under the trend of continuous development of graphene preparation technology, the quality of graphene has been greatly improved compared with before, and we can expect that the performance of graphene batteries in the future will have a greater performance improvement. In recent years, the market prospects for emerging electronic products such as wearable devices and wireless Bluetooth speakers are promising. With the progress of intelligence, the market demand for 3C lithium batteries is expected to continue to grow. For lithium battery companies, they should grasp the market development trend, fully tap the market demand for emerging electronic products, and develop high-safety, high-rate 3C lithium-ion batteries.