Amorphous lithium will promote the development of new high-performance batteries
researchers have begun to study the deposition kinetics of lithium in the battery cycle. By changing different parameters, they found that it is relatively easy to convert lithium into amorphous, which is superior at the electromechanical levelThe higher the amorphous degree of
metal, the better its electrochemical performance in the battery. However, the synonym of lithium in the battery industry mainly appears in the form of crystal - leading to many problems in its behavior in lithium-ion batteries
the production of amorphous metals is particularly challenging. However, a group of battery materials researchers recently discovered a way to make amorphous metals (including lithium) in batteries, which is more or less accidental. A team from the Idaho National Laboratory and the University of San Diego studied the atomic level of lithium-ion batteries a few minutes before charging
the electrochemical reversibility of lithium was discussed in "glass lithium metal anode of high performance rechargeable lithium battery" recently published in nature materials. This reversibility determines that the form of lithium contributes its due pneumatic and electrical properties to improving the localization rate of materials in civil aircraft industry. Therefore, a better understanding of this process can promote the development of high-performance batteries
when the battery circulates, its lithium ion is deposited on the anode. The first stage of the process is called nucleation, in which the first part of the metal ions form a starting point from which the remaining crystalline metal particles grow. Using a low-temperature transmission electron microscope, the team successfully visualized the initial deposition of lithium metal on the anode for the first time. When lithium is deposited in crystal form, the main nucleation determines the way in which the remaining lithium grows around it. The researchers call this process "lithium embryo growth"
according to an article in the journal Nature materials, "based on the interaction between atoms during initial nucleation (for example, atomic bulk density, mass transfer and energy transfer), the nanostructure of lithium nuclei can change from disorder to order, and finally form the final microstructure and affect the performance."
when lithium is too crystalline, the charge is inconsistent, which then leads to dendritic formation - growth of irregularly shaped crystals. Such dendrites greatly shorten the battery life. Shirley Meng, a pioneering cryomicroscope researcher at the University of California, San Diego, said: "the ability of low-temperature imaging to discover new phenomena in material science has been demonstrated in this work. Real teamwork enables us to interpret experimental data confidently because computational models help explain complexity."
to the researchers' surprise, their experiment allowed them to observe pure amorphous metal elements for the first time. The slow charging rate also provides favorable conditions for the growth of amorphous lithium
previously, researchers assumed that a slower charging rate would lead to a slower deposition rate, giving lithium ions more time to find an orderly structure for arrangement, thus forming unfavorable crystalline lithium
in addition to adjusting the charge current to achieve a slower deposition rate, researchers also used different electrolytes. In the "baseline" electrolyte, about 48% of lithium is amorphous
however, 76% of the electrolytes appeared in amorphous form when using the advanced electrolytes described by the researchers. In both cases, the rest form a crystal structure
research shows that glassy metal deposits can be produced by changing the time and space constraints of material and energy transfer in different ways. These strategies include methods to reduce current density, design of advanced electrolyte composition, and use of 3D current collectors
the researchers said: "these strategies can change the bulk microstructure of lithium metal electrode and obtain larger and more uniform lithium deposition, so as to improve the cycle performance."
the researchers concluded: "in addition to metallic glass and energy storage, these new amorphous active metals will open up new opportunities in various application fields, including biomedicine, nanotechnology and MEMS."
according to the micro lithium battery team, the investigation team also found other metals that may be of interest to the battery industry. They include sodium, potassium, manganese and zinc. Amorphous metals do not produce dendritic crystals, so they can not only improve the oil output and performance of the oil return pipe of the electrochemical oil delivery valve, but also significantly improve the service life of the battery广州产后一年斑秃严重怎么办
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