What are the advantages of lithium batteries in performance

Using graphite or petroleum coke and other carbonaceous lithium intercalation compounds instead of metallic lithium as the negative electrode will cause the battery voltage to drop. However, due to their low lithium insertion potential, the voltage loss can be reduced to a minimum. At the same time, choosing an appropriate lithium intercalation compound as the battery's positive electrode and choosing an appropriate electrolyte system (which determines the electrochemical window of the lithium battery) can make the lithium battery have a higher working voltage (-4V), which is much higher than that of the aqueous system battery. . (2) Large specific capacity Although replacing metal lithium with carbonaceous materials will reduce the specific capacity of the material, in fact, in order to ensure the battery has a certain cycle life in metal lithium secondary batteries, the negative metal lithium is usually more than three times excessive Therefore, the actual decrease in the mass specific capacity of the lithium battery is not large, and the volume specific capacity hardly decreases. (3) The higher energy density and higher working voltage and volumetric specific capacity determine the higher energy density of the secondary lithium battery. Compared with the widely used Ni-Cd batteries and Ni-MH batteries, secondary lithium batteries have the highest energy density and still have great potential for development. (4) Good safety performance and long cycle life. The reason why batteries using lithium metal as anode are unsafe is that multiple charge and discharge changes the structure of the positive electrode of the lithium battery, forming porous dendrites. When the temperature rises, it interacts with the electrolyte. A violent exothermic reaction, and dendrites can pierce the diaphragm, causing an internal short circuit. Lithium batteries do not have this problem and are very safe. In order to guard against the presence of metallic lithium in the battery, the voltage must be controlled when charging. For the sake of safety, the lithium battery is equipped with multiple safety devices. During the charging and discharging process of lithium batteries, there is no structural change in the insertion and deintercalation of lithium ions on the cathode and anode (the lattice will expand and contract during the insertion and deintercalation process), and because the lithium intercalation compound is more than metal lithium It is stable and does not form lithium dendrites during charging and discharging, thus clearly improving the safety performance of the battery, and at the same time greatly improving the cycle life. Lithium batteries were excluded as dangerous goods by the Dangerous Goods Transportation Division of the U.S. Department of Transportation and IAIT (International Aviation and Transportation Association) in 1989 and 1990, respectively. (5) Low self-discharge rate Lithium battery adopts non-aqueous electrolyte system, and lithium-intercalated carbon material is thermodynamically unstable in non-aqueous electrolyte system. During the first charge and discharge process, due to the reduction of the electrolyte, a solid electrolyte intermediate (SEI) film is formed on the surface of the carbon negative electrode, allowing lithium ions to pass but not allowing electrons to pass, and making the electrode active materials of different charged states. It is in a relatively stable state, so it has a low self-discharge rate. (6) Clean and pollution-free lithium batteries do not contain toxic substances such as lead, fu, mercury, and because the battery must be well sealed, there is very little in use Gas is released, which does not cause pollution to the environment. The solvent used to dissolve the binder during the manufacturing process can also be completely recovered. Large-scale lithium battery processing companies such as Sony have successively begun the recycling and material recycling of lithium batteries since 1997 (Such as metal drills, etc.). In addition, in 1996, Sony’s lithium battery was certified to meet the IS014001 international environmental standard [71O(7) High current efficiency is different from any previous secondary battery with aqueous solution system. The lithium battery is in normal condition. There will be no gas during the charging and discharging process, and the current efficiency is close to 100%. This property is particularly suitable for battery packs for power storage and conversion. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please Contact to delete the previous article: Which types of lithium battery electrolyte