China Energy Storage Network News: Recently, the Shenyang National (Joint) Laboratory of Materials Science, Institute of Metal Research, Chinese Academy of Sciences, has prepared a graphene foam with a three-dimensional connected network structure in the early stage, and used the material as a highly conductive flexible current collector. And prepared a flexible lithium-ion battery that can be quickly charged and discharged. Related research results were recently published online in the Proceedings of the National Academy of Sciences of the United States.
Thinning and flexibility are important development trends of portable electronic products, and energy storage devices are the core components of portable electronic products. Therefore, whether high-performance flexible energy storage devices, such as flexible lithium-ion batteries, can be developed for a wide range of flexible electronic products One of the key issues of the application. Studies have found that the high conductivity and good flexibility of graphene are one of the ideal candidate materials for flexible energy storage devices.
Researchers in the laboratory used the three-dimensional connected graphene network as the current collector, replacing the metal current collector commonly used in batteries, and through the developed in-situ hydrothermal synthesis method, the active material was directly grown on the graphene three-dimensional connected network structure. For example, lithium iron phosphate and lithium titanate have successfully achieved good contact between the active material and the graphene current collector without the use of binders and conductive additives, which has promoted the transmission of electrons and improved the electrode material's performance during bending. stability.
In the end, the researchers used lithium iron phosphate/graphene and lithium titanate/graphene composite materials as the positive and negative electrodes, respectively, and used flexible silica gel as the package to assemble a fully flexible lithium-ion battery. Experiments show that when the flexible lithium-ion battery is bent, its charge and discharge characteristics remain unchanged, and can be charged within 6 minutes (reaching 90% of the initial capacity), and the capacity retention rate is 96% after 100 cycles.
Industry experts believe that this research provides a new idea for the design and preparation of high-performance flexible lithium-ion batteries. The fast-charging flexible lithium-ion battery has a simple preparation process and has potential practical application value.
The research was funded by related projects of the National Natural Science Foundation of China, the Ministry of Science and Technology and the Chinese Academy of Sciences.
