Major breakthrough! In the future, battery life will therefore be found to **increase**

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At the beginning of the 21st century, rechargeable devices powered by lithium batteries were widely used in various fields, including mobile devices and new energy vehicles, bringing tremendous value to humanity. However, during the development process, the significant volume change of the anode material itself during lithium ion insertion can lead to a series of material collapse and amorphization phenomena. Significant progress has been made regarding the issue of battery structure collapse, but for years, scientists have been at a loss as to how to address battery amorphization. A turning point came with the application of sodium ions; due to their lower cost and greater availability, they are set to become the preferred alternative to lithium batteries in the future. However, the volume change that occurs during the charging and discharging process of sodium ions is much greater compared to that of lithium batteries. Not long ago, scientists at Fudan University in China made breakthrough progress in the study of reversible crystalline phase transitions in anode materials for sodium-ion batteries. The researchers used a series of polyphenyl metal molecules containing metal centers as a single reaction source; by leveraging the π-π stacking effect of the benzene rings, these polyphenyl molecules were decomposed and deposited in situ on the tube walls within closed vacuum quartz tubes, through a temperature-controlled process. This resulted in binary metal/carbon nanocomposite films in which metal or alloy nanoparticles (Sb, Bi, Sn, Ge, Sb89Bi11) with diameters of less than 5 nanometers were uniformly dispersed within a graphitized carbon framework. The prepared composite membrane exhibits excellent processability and conductivity comparable to that of graphite, allowing it to be used directly as an electrode material for sodium-ion batteries without the need for conductive agents. Therefore, the electrode active material can rapidly return from an amorphous state to a crystalline state after each charge-discharge cycle. This unusual reversible crystalline phase transition ensures extremely high cycle stability and high power performance for the electrodes; even after 5,000 cycles at high current densities of 5C and 7.5C, the battery’s capacity shows almost no degradation, and the structure of the electrode material remains intact. The article is sourced from Mofan Network