New energy vehicle batteries are lithium batteries. We found that as a high-power battery, lithium-ion batteries have outstanding advantages:
1) High specific power. The average operating voltage of lithium-ion batteries is 3.6 V, which is three times the operating voltage of nickel-cadmium and nickel-metal hydride batteries. The battery can release higher power per unit weight;
2) High specific energy. The specific energy of lithium-ion batteries can currently reach 140 Wh/kg, which is much higher than that of nickel-metal hydride and lead-acid batteries. It can store more energy per unit weight;
3) Long lifespan. At present, the lifespan of lithium-ion batteries has reached more than 1,000 times, and can reach tens of thousands of times at low depth of discharge. Performance;
4) Small autodcharge. The monthly self-discharge rate of lithium-ion batteries is only 6-8%, which is lower than that of nickel-cadmium batteries (25-30%) and nickel-metal hydride batteries (30- 40%);
5) No memory effect. It can be charged at any time as needed without reducing battery performance;
6) No pollution to the environment. There are no harmful substances in lithium-ion batteries.
The lithium battery industry chain structure is optimistic about key components such as cathode materials, separators and electrolytes. The purchase cost of lithium battery parts is composed as follows: the purchase cost of positive electrode materials (including aluminum casing) accounts for about 30% of the total cost, the purchase cost of materials of negative electrode (including copper foil) accounts for about 20%, and the separator materials account for approx.iron 20% of the total cost. , the electrolyte accounts for about 20% of the purchase cost, and structural parts such as the battery case account for about 10% of the battery cost.
Cathode material: Cathode material has a great influence on the performance of the battery and is one of the key components of the battery. Lithium iron phosphate material is a developed lithium-ion battery material. As a vehicle electric energy storage device, safety performance requires special attention. Although lithium cobalt oxide batteries and ternary material batteries have the advantages of being lighter and smaller in size, they are not suitable for use as power batteries in electric vehicles. From the current performance comparison of various lithium-ion batteries, we can see that lithium-ion batteriesm-iron-phosphate are the lithium-ion batteries currently used in the industrial application of electric vehicles. Therefore, companies that master the technology of large-scale production of lithium iron phosphate and lithium iron phosphate batteries will occupy a leading position in the future competition in the electric vehicle industry.
Anode materials: Among the anode materials of lithium ion batteries, graphite type carbon anode materials have always been the main type of anode materials cards their wide sources and prices down. In addition to graphitized mesophase carbon microspheres and low-end artificial graphite which occupy a small part of the market, modified natural graphite is increasingly the subject of patents. In recent years, lithium titanate materials have gradually begun to be used as negative electrodes.
Electrolyte: The electrolyte plays a role in the conduction of electrons between the positive and negative electrodes of the battery. The main raw material of the electrolyte is lithium hexafluorophosphate, which accounts for more than 50% of the cost of the electrolyte, and the gross profit margin reaches 75%. The lithium and fluorine in lithium hexafluorophosphate are both rare resources. my country has restricted the export of fluorspar and will definitely restrict the export of hydrofluoric acid in the future. China\'s lithium and fluorine resources are among the best. It has the resource base to develop materials related to lithium batteries and has cost advantages. It will surely occupy an important position in the field of lithium battery materials in the future. It is worth looking forward to.
Separator: In the structure of the lithium battery, the separator is one of the componentss key internals. The popular description of the separator is a layer of porous plastic film. It is a high value-added material that has the highest technical barriers among lithium battery materials, accounting for approximately 1/3 of the battery cost. The performance of the separator determines the interface structure, internal resistance, etc. of the battery, which directly affects the battery capacity, cycle performance, safety performance and other characteristics. Excellent separators play an important role in improving the overall performance of the battery.
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