Analysis of the structure, principle and characteristics of lithium iron phosphate battery

Lithium iron phosphate electrode materials are critically used in various lithium batteries. Since 1996, NTT in Japan first revealed the olivine structure positive electrode material of AyMPO4 (A is an alkali metal, M is a combination of CoFe: LiFeCOPO4), 1997 The research group of Texas State University in the United States also reported on the reversible migration of LiFePO4 in and out of lithium in the United States. The United States and Japan coincidentally published the olivine structure (LiMPO4), which made the material receive great attention. Caused extensive research and rapid development. Compared with traditional lithium ion secondary battery cathode materials, spinel structured LiMn2O4 and layered structured LiCoO2, LiMPO4 has a wider source of raw materials, is cheaper and has no environmental pollution. The rechargeable battery of the lithium iron phosphate battery is a lithium battery with a lithium iron phosphate battery as the cathode material. Lithium phosphate lithium battery is a positive potential of a rechargeable battery packaged with aluminum platinum and a rechargeable battery, with a polymer membrane in the middle, which separates the positive and negative potentials, but lithium batteries can be based on, but electronic devices cannot. The negative potential of a rechargeable battery composed of carbon (high purity graphite) is connected by the negative cascade of copper and the rechargeable battery. The upper and lower middle parts of the rechargeable battery are the electrolyte solution of the rechargeable battery, which is sealed by a plastic casing. The lithium battery in the battery transfers to the negative phase according to the polymer film. The lithium battery should be 10-3210-3s/cm, the conductivity is high, the transfer number of the lithium battery should be close to 1, and the potential difference range is wide. With the processing of important domestic raw materials, the cost of lithium battery electrolytes has been further reduced, and Korean and Japanese companies have also begun to move their manufacturing plants to my country. First of all, it is necessary to prepare lithium battery electrolyte, and the industrial prospect of electrolyte is very broad. Lithium battery electrolyte is also a level that cannot be ignored. Lithium battery electrolyte accounts for 15% of the cost of lithium batteries. It plays a particularly important role in specific energy, power, wide-temperature use, cycle life, and safety factor. Lithium iron phosphate battery is a lithium battery with lithium iron phosphate battery as the cathode material. Lithium iron phosphate battery is a positive potential of a rechargeable battery packaged with aluminum platinum and a rechargeable battery, with a polymer membrane in the middle, which separates the positive and negative potentials, but lithium batteries can be based on, but electronic devices cannot. The negative potential of a rechargeable battery composed of carbon (high purity graphite) is connected by the negative cascade of copper and the rechargeable battery. The upper and lower middle parts of the rechargeable battery are the electrolyte solution of the rechargeable battery, which is sealed by a plastic casing. The lithium battery in the battery transfers to the negative phase according to the polymer film. Principles and characteristics of lithium iron phosphate batteries The battery generally includes: positive electrode, negative electrode, electrolyte, separator, positive lead, negative lead, center terminal, insulating material, safety valve, sealing ring, PTC (positive temperature control terminal), battery case, etc. Among them, the difference in the positive electrode material, the negative electrode material, the electrolyte and the separator or the difference in the process have a decisive influence on the performance and price of the battery. Lithium batteries are commonly referred to as batteries with various lithium-containing materials as the cathode material. The current lithium battery cathode materials on the market are lithium cobalt oxide (LiCoO2) and lithium manganese oxide (LiMn2O4). In addition, there are a few that use nickel. Lithium oxide (LiNiO2) and binary/ternary polymers are used as cathode materials for lithium batteries. Lithium iron phosphate battery is a lithium battery that uses lithium iron phosphate (LiFePO4, LFP for short) as the positive electrode of the battery. Its internal structure is shown in Figure 1: On the left is LiFePO4 with olivine structure as the positive electrode of the battery, which is connected to the positive electrode of the battery by aluminum foil , In the middle is a polymer separator, which separates the positive and negative electrodes, but lithium ions Li+ can pass but electrons e- cannot pass. On the right is the battery negative electrode composed of carbon (graphite), which is connected to the battery negative electrode by copper foil. Between the upper and lower ends of the battery is the electrolyte of the battery, and the battery is hermetically sealed by a metal shell, an aluminum-plastic composite film or a plastic shell. The working principle of the LiFePO4 battery is: when the battery is charged, the lithium ions in the positive electrode material are released, pass through the electrolyte, pass through the diaphragm and enter the negative electrode material; when the battery is discharged, the lithium ions are released from the negative electrode and pass through the electrolyte. Go through the separator and return to the positive electrode material. (Note: Lithium battery is named because lithium ion moves back and forth during charging and discharging, so lithium battery is also called rocking chair battery) 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 one Article: What are the influencing factors of the internal resistance of lithium iron phosphate batteries