What will happen to the development of lithium batteries in the future

Due to its high energy density and high electrochemical potential, lithium batteries (LIB) have become one of the most popular choices in the world. Since its development in the 1970s, LIB has achieved significant technological innovation, and Sony launched its first rechargeable battery in 1991. Rechargeable batteries rely on electrochemical reactions. Through the movement of ions and electrons in the electrolyte between the anode and cathode electrodes, chemical energy is converted into electrical energy, and vice versa. How the development of lithium batteries will look in the future Figure 1: Schematic diagram of the working principle of lithium batteries (Charge: Charge, Discharge, Electrolyte Separator) In the first charging cycle of LIB, when lithium ions flow through the electrolyte to the anode, Some of them will react with the degradation products of the electrolyte to form insoluble deposits on the anode. These deposits form a solid electrolyte interphase (SEI), which is critical to the long-term operation of the battery. The formation of stable SEI that can conduct ions and insulate electrons determines many performance parameters, so the research on LIB is very attractive. Using NMR to study LIBNMR technology can be used to study the specific structural information (including electronic structure) of a variety of battery systems, such as identifying intermediate products, studying the dynamic characteristics of battery materials, and so on. NMR is particularly suitable for studying the kinetic properties of alkali metal ions, which are the key components of battery materials. Even in a highly disordered system, solid-state NMR can be used to characterize the local structure of LIB materials and clarify the signal transformation of various chemical substances in the material. Lithium has two NMR active isotopes (6Li and 7Li), so it is possible to directly study the kinetic characteristics of lithium and quantitatively decompose the movement of lithium ions. The development of NMR technology helps to improve the understanding of SEI, enabling researchers to separate and quantitatively identify SEI membranes from multiple aspects. For example, using 7Li and 19F magic angle rotation (MAS) NMR technology, it is possible to identify and quantitatively study the change of lithium fluoride (LiF) in the SEI film between the recharged LIB anode and the electrolyte. The 1NMR method can also monitor the growth of dendrites and do quantitative decomposition. The change of Li peak intensity during the cycle of charging and discharging is related to the growth of dendritic structure and the smooth deposition of metal. The study found that it can be determined by in-situ NMR that up to 90% of the lithium deposited during the slow charging of the Li/LiCoO2 battery is dendritic. 2NMR can be used to systematically detect methods of inhibiting dendrite growth such as electrolyte additives, advanced diaphragms, battery pressure, temperature and electrochemical cycling conditions. 3 Coupled with in-situ quantitative monitoring of SEI and new battery materials, NMR has played a key role in promoting the design of innovative LIBs. Is EPR a complementary technology? Measuring the formation of dendrites during battery operation is quite challenging, but continued research on alternative LIB designs and materials is necessary. In addition to NMR, EPR spectroscopy is also very suitable for in-situ study of the evolution of metallic lithium species. EPR spectroscopy has also been used for semi-quantitative testing of deposited lithium metal in LIBs using metallic lithium anodes and LiCoO2 cathodes. EPR imaging technology is being used to study the relationship between the formation and disappearance of free radical oxygen species in new batteries and current, potential, resting time, electrolyte or temperature. Using MRI to obtain spatial information In addition to spectroscopy, MRI is also a powerful non-invasive technology that can provide time discrimination and quantitative information about changes in the electrolyte and electrodes of LIB. Similar to NMR, MRI can test and locate the microstructure of lithium, and also has the magical advantage of providing spatial information, so that it can locate specific structural changes. The advantages of MRI technology in the research of new battery materials and battery design are increasingly recognized. Other uses include LIB capacity decay studies, battery testing after a large number of cycles, high stress and accelerated aging experiments. One of the most cutting-edge researches on LIB in all-solid-state batteries is the transition from liquid electrolyte to solid electrolyte. Considering the possibility of a short circuit in the LIB, the flammability of the liquid electrolyte means a safety hazard. For many years, researchers have been studying the use of solid electrolytes to replace liquid electrolytes, which can not only improve safety, but also provide lithium metal anodes with the potential to resist dendrite formation, thereby increasing energy density. Although the all-solid-state battery is not a new concept, its progress has been hindered so far due to its poor rate performance and cycle performance (perhaps due to the high internal resistance of lithium ion transfer at the solid-solid electrode-electrolyte interface) [4] . 5 Therefore, the study of interface counter-response charge transport is crucial to realize the potential of these batteries, and NMR is the ideal choice in this regard. NMR also helps characterize potential solid electrolyte materials, such as ceramics that rely on ion transport. NMR combined with conductivity measurement can be used to decompose ion kinetic characteristics and help clarify the relationship between local structure and kinetic parameters. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: Analysis of UPS battery safety operation specifications and charging precautions