Analysis on the operating principle of lithium batteries

Analyze the working principle of lithium batteriesThe working principle of lithium batteries: The lithium atom data of the positive electrode is generally relatively simple and backward. When charging, the lithium atom of the positive electrode becomes lithium ions, and then through the transmission of the electrolyte, through the gap of the central pore structure, The negative electrode is stored in graphite. During the discharge process, lithium ions are released from the negative electrode, transported by the electrolyte, and return to the positive electrode data through the gap. This is the charging and discharging process of the lithium battery. It swings from side to side like a person sitting on a rocking chair. Lithium batteries were introduced into my country in the late 1990s. After more than two decades of development, in the secondary battery (non-disposable battery) market, lithium batteries are still a niche group related to lead-acid batteries and nickel-chromium-nickel metal hydride batteries. According to the survey, the current market share is about 20-30%. Advantages of lithium batteries. For example, the operating voltage of a lithium battery can reach between 3.5v and 3.8v, and a lithium battery developed in the laboratory can reach up to 5V. In addition, lithium batteries are better in capacity and energy density. The above two characteristics are generally more than twice as good as traditional nickel-chromium-nickel metal hydride batteries. Lithium batteries are also more environmentally friendly. Generally speaking, lithium batteries are mainly composed of three parts: positive electrode, negative electrode and electrolyte. The research on positive electrode materials in our country is relatively early, and the industrial development is relatively early. Generally commercial: manganese series materials with lithium manganate layered structure, spinel and olivine structure, and lithium iron phosphate series. Only graphite is a commercially available negative. Unlike traditional secondary batteries, the electrolyte of lithium batteries is an organic electrolyte. This liquid electrolyte composed of organic matter is flammable with respect to water-based electrolytes, which is a serious safety hazard. The demand pointed out that the current common commercial electrolytic salt is a material called lithium hexafluorophosphate. One of the characteristics of this substance is that when the ambient temperature reaches 60 degrees Celsius, it will decompose, and this temperature is easily reached when using the mobile phone daily. Lithium hexafluorophosphate will also release gaseous substances during the decomposition process, which poses a great safety hazard. In addition to the above three blocks, another more important component of lithium batteries is the gap. The gap is generally composed of a plastic film made of PP or PE material, and its important purpose is to isolate the positive and negative electrodes of the battery to prevent short circuits. It should be pointed out that in order to ensure a smooth lithium ion charging and discharging process, an absolutely uniform pore size distribution structure is required. The manufacturing process requirements are very high, and there is no gap in the early domestic processing capacity. Here, the technological level of the barrier also plays an important role in battery safety. According to the working principle of lithium ions, it is known that lithium ions are transmitted back and forth in the electrolyte. First, the viscosity of the electrolyte is required not to be too large. If it is too large, it will form transmission resistance and cause local overheating. Secondly, it should be ensured to meet the gap of Xiaochang, and have a certain strength, the gap cannot hinder the lithium ion channel, nor can it be damaged through several charging and discharging processes or pore size increase. This is an important condition to ensure the safety of lithium batteries. Disclaimer: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: Analysis of the service life of laptop batteries