What is the difference between the square, cylindrical and soft packs of lithium iron batteries?

Square lithium battery usually refers to aluminum shell or steel shell square battery. The popularity of square battery is very high in China. With the rise of automobile power lithium-ion batteries in recent years, the contradiction between automobile mileage and battery capacity has become increasingly prominent. Lithium-ion battery manufacturers mostly use aluminum shell prismatic batteries with higher battery energy density, because the structure of prismatic batteries is relatively simple, unlike cylindrical batteries that use high-strength stainless steel as the shell and accessories with explosion-proof safety valves, so The overall accessory should be light in weight and relatively high in energy density. Square batteries have two different processes: winding and lamination. Cylindrical battery Cylindrical battery is mainly steel-shell cylindrical lithium iron phosphate battery. This battery is characterized by high capacity, high output voltage, good charge and discharge cycle performance, stable output voltage, large current discharge, stable electrochemical performance, It is safe to use, wide operating temperature range, and environmentally friendly. It is widely used in solar lamps, lawn lamps, back-up energy, power tools, toy models. The structure of a typical cylindrical battery includes: a positive electrode cover, a safety valve, a PTC element, a current cut-off mechanism, a gasket, a positive electrode, a negative electrode, a separator, and a casing. Soft pack battery The soft pack battery is a liquid lithium battery covered with a polymer shell. The biggest difference from other batteries is the soft packaging material (aluminum-plastic composite film), which is also the most critical and technically difficult soft pack lithium battery. material. The packaging material and structure of the soft pack battery make it have many advantages. Advantages and disadvantages of square, cylindrical and soft-packed iron-lithium batteries ●Advantages of cylindrical iron-lithium batteries: Cylindrical iron-lithium batteries are the earliest mature industrialized lithium battery products. After more than 20 years of development, cylindrical lithium batteries are now processed The technology is mature, the processing efficiency is high, and the cost is relatively low, so the cost of PACK is relatively low. The yield of lithium batteries is higher than that of square lithium batteries and soft-pack lithium batteries, and its consistency and safety are also excellent. Disadvantages: Because the cylindrical iron-lithium battery is generally packaged in a steel shell, although the safety is relatively high, the weight will also be heavier, which will also make the specific energy of the lithium battery pack relatively low. ●Advantages of prismatic lithium iron batteries: the packaging shells of prismatic lithium iron batteries are mostly made of aluminum alloy and stainless steel. The inside of the battery adopts a winding or laminated process, and the protection of the battery core is better than that of the soft pack lithium battery. Compared with the cylindrical lithium battery, the safety of the battery cell is also greatly improved. Disadvantages: Because the square lithium iron battery pack can be customized according to the size of the product, it will also make the market have many different types of square lithium batteries. Too many different types of lithium batteries will make it difficult to unify the process, making the automation level not high, the monomers are quite different, and there may also be groups of square lithium battery packs that are far less than the life of a single lithium battery. ●Advantages of soft-packed lithium iron batteries: The soft-packed lithium iron batteries use polymer electrolytes and soft packaging materials, which are the most critical and technically difficult materials in soft-packed lithium batteries. The soft packaging material means that the soft pack lithium battery can also be customized according to the requirements of customers. Soft pack lithium batteries are not explosive like square lithium batteries and cylindrical lithium batteries, and they are lighter than other batteries. Disadvantages: Although the shape of the soft-packed iron-lithium battery can be customized according to the needs of customers, the existing soft-packed batteries have fewer models and cannot meet the needs of the market, and the cost of developing new models is relatively high. In addition to the high development cost, the material cost of soft-pack lithium batteries is higher than that of cylindrical and square batteries. The cost issue is the focus of soft-pack lithium battery companies to break through in the future. 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: What are the charging methods for car lithium batteries?