How can we achieve longevity of lithium-ion batteries?

First of all, too high and too low power states have the most adverse impact on the life of lithium-ion batteries, and the number of charge and discharge cycles is secondary. In fact, the number of rechargeable cycles marked on most of the electrical appliances or batteries sold is based on 80% discharge as a benchmark test. Experiments have shown that for some laptop lithium-ion batteries, the battery voltage often exceeds the standard voltage by 0.1 volts, that is, from 4.1 volts to 4.2 volts, then the battery life will be halved, and if it is increased by 0.1 volts, the life will be reduced to the original One-third; the long-term low or no power state will make the internal resistance of the battery to the movement of electrons become greater and greater, thus causing the battery capacity to become smaller. NASA has set the battery power consumption on its Hubble Space Telescope at 10% of the total capacity to ensure that the battery can be repeatedly charged and discharged 100,000 times without having to update. Secondly, temperature also has a greater impact on the life of lithium-ion batteries (mobile phones and other small electronic devices can be ignored). The environment below the freezing point may cause the lithium-ion battery to burn out when the electronic product is turned on, and the overheated environment will reduce the battery capacity. Therefore, if the notebook is used for a long time with an external power source and the battery is not removed, the battery will be in the high heat discharged from the notebook for a long time. More importantly, the battery will be in a state of 100% power for a long time and will soon be scrapped (including me This is how I finished playing with my laptop battery). From the above, we can sum up the following points for precautions to ensure the capacity and life of the lithium-ion battery: • Do not charge the lithium-ion battery to 100% full, let alone use up the power. When the situation permits, try to keep the battery power near the half-full state. The smaller the charge and discharge range, the better; Li-ion batteries will appear dendrites during use, and dendrite breakage will not only cause the battery capacity to decrease , The life is discounted, and it may pierce the diaphragm and cause the battery to short-circuit and catch fire, causing safety problems. The research group of Professor Liang Jiajie and Professor Chen Yongsheng of Nankai University and the research group of Jiangsu Normal University Lai Chao proposed a new optimization strategy to solve this problem, and successfully prepared a three-dimensional porous graphene carrier with silver nanowires with a multi-level structure, and loaded metal lithium as Composite anode material. This carrier can inhibit the appearance of lithium dendrites, which can realize ultra-high-speed battery charging, which is expected to greatly extend the life of lithium-ion batteries. In recent years, many countries around the world have made important breakthroughs in the design and synthesis of lithium anode materials. However, it has still not been able to suppress the appearance of dendrites and the volume expansion of electrodes under high current density charging and discharging of lithium metal. Long life, large capacity, fast charge and fast release are still insurmountable. Depositing metallic lithium into a porous current collector with a three-dimensional network structure to construct a metallic lithium composite negative electrode material is currently one of the effective ways to solve the above-mentioned difficulties. Liang Jiajie said. Based on this understanding, the research group first proposed the selection and optimization strategy of ideal metal lithium anode three-dimensional carrier materials to achieve ultra-high current density and ultra-long cycle life. They used the macroscopic three-dimensional network of graphene as the mechanical framework and the two-dimensional network of silver nanowires as the conductive structure. They prepared the three-dimensional silver nanowire graphene graphene with a hierarchical structure through a low-cost coating and cold drying method compatible with industrial production Porous carrier, and supporting metal lithium as a metal lithium composite negative electrode material. After testing, the specific capacity of the metal-lithium composite anode material can reach 2573mAh/g; in the symmetrical battery test, it is the first time to achieve repeated charging and discharging for more than 1000 cycles at a very high current density of 40mAh/cm2, and the overpotential is less than 120 millivolts . It can be seen through electron microscope observation that the multi-level three-dimensional structure carrier can successfully inhibit the growth of lithium dendrites in the metal lithium negative electrode and the volume change of the electrode even under the cycle conditions of extremely high current charge and discharge. 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 post: What is the difference between dry battery and lithium ion battery