Expanded graphite material as well as preparation method and application thereof

• Main Authors: ZHONG SHICHANG, DONG SIXIAO, ZHAO WENWEN, ZHANG HUI
• Format: Patent
• Language: Chinese; English
• Published: 28.05.2024
• Subjects: BASIC ELECTRIC ELEMENTS; CHEMISTRY; COMPOUNDS THEREOF; ELECTRICITY; INORGANIC CHEMISTRY; METALLURGY; NON-METALLIC ELEMENTS; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

The invention relates to the field of secondary batteries, in particular to an expanded graphite material and a preparation method and application thereof, and the expanded graphite material comprises an inner core and a hard carbon shell coating the outer surface of the inner core; the inner core is expanded graphite with a layered structure, and a hard carbon layer is mingled between adjacent layers of the expanded graphite; the distance between adjacent layers of the expanded graphite is larger than or equal to the radius of sodium ions. Compared with a negative electrode material for a sodium ion battery, the expanded graphite material provided by the invention takes graphite as an active main body, the carbon yield is higher, the expanded graphite of which the lamellar structure can be controlled is adopted as a basis, a hard carbon layer is mingled between adjacent layers of the expanded graphite, and the distance between the adjacent layers of the expanded graphite is greater than or equal to the radiu