Why are graphite products widely used in the field of lithium batteries?

Graphite is a material with a unique structure and properties, possessing excellent conductivity, chemical stability, and thermal stability, making it widely used in the field of lithium batteries. The following will provide a detailed introduction to the reasons for the application of graphite products in the field of lithium batteries.

Firstly, graphite plays an important role as a negative electrode material in lithium-ion batteries. Lithium ion batteries have been widely used in electric vehicles, mobile phones, electronic devices, and other fields due to their high energy density, high open circuit voltage, and long cycle life. As a negative electrode material, graphite can effectively store and release lithium ions in lithium-ion batteries, and is one of the core components of lithium-ion batteries. The layered structure and open channel structure of graphite enable reversible insertion and extraction reactions of lithium ions inside graphite, thereby achieving the storage and release of lithium ions. Moreover, graphite has high electrical conductivity and good mechanical properties, which can withstand the volume and stress changes during the insertion and extraction of lithium ions. Therefore, graphite plays a crucial role in storing and releasing lithium ions as a negative electrode material in lithium-ion batteries.

Secondly, graphite products also play an important role in the electrolyte of lithium-ion batteries. Electrolyte is an important component of lithium-ion batteries, which can provide a conduction channel for lithium ions, allowing them to be embedded from the negative electrode material into the positive electrode material. Graphite products have a large specific surface area and abundant surface functional groups, which can increase the contact area between the electrolyte and graphite, promote the adsorption and desorption of lithium ions on the graphite surface, and improve the transmission rate of lithium ions. In addition, the functional groups on the surface of graphite can also form coordination bonds with solvents and salts in the electrolyte, improving the stability of the electrolyte and the transport performance of lithium ions. Therefore, adding graphite products to the electrolyte of lithium-ion batteries can improve the conductivity of lithium ions and the cycle life of the battery.

In addition, graphite products also have important applications in the separator of lithium-ion batteries. As a key component in lithium-ion batteries, the separator can prevent direct contact between the positive and negative electrode materials while allowing for the transfer of lithium ions. Graphite products can be used for the preparation of modified membranes. By spraying a graphite conductive layer on the surface of the membrane, the conductivity of the membrane can be increased and the lithium ion conductivity can be improved. In addition, the graphite conductive layer can absorb and disperse local heat, serving as a protective membrane and reducing the risk of thermal runaway. Therefore, the application of graphite products in the modification of separators in lithium-ion batteries can improve the safety and cycle life of the battery.

In addition, graphite products can also be used for the modification of positive electrode materials for lithium-ion batteries. The positive electrode material of lithium-ion batteries is usually a composite material composed of lithium salt and conductive and insulating agents that are resistant to high temperature and high pressure. Due to its unique structure and properties, graphite can be applied in the preparation of modified positive electrode materials. By adding an appropriate amount of graphite powder to the positive electrode material, the conductivity of the positive electrode material can be increased, and the overall conductivity of the electrode can be improved, thereby increasing the charging and discharging rate and energy density of the battery. In addition, graphite can improve the chemical and thermal stability of positive electrode materials, and suppress the structural degradation of positive electrode materials during charge and discharge processes