Experts discuss the technical route selection and manufacturing process  selection of lithium batteries. Can the large cylinder break through?

　　"By the end of this year, the penetration rate of new energy vehicles in my  country will reach 35%." Wang Chuanfu, president of BYD, said at the 2022 China  Electric Vehicle Hundred People's Conference.

　　Wang Chuanfu's views have also been echoed. Changan Automobile believes  that 80% of Chinese fuel vehicle brands will "shut down and turn around" in the  next 3-5 years. Ouyang Minggao, an academician of the Chinese Academy of  Sciences, also said that in 2022, the sales of traditional fuel vehicles will  basically be close to the peak, while new energy vehicles will enter a period of  rapid growth.

　　On the one hand, the accelerated development of the new energy vehicle  industry has an obvious substitution effect on fuel vehicles; on the other hand,  supply chain constraints are still the bottleneck restricting its further  expansion. The tight battery supply situation is not expected to change this  year. The current tight supply of upstream raw materials for power batteries is  mainly due to the long expansion cycle of mineral resources, the room for  improvement in mining technology, and the impact of overseas mineral production  capacity.

　　Compared with ternary lithium batteries that require rare metals such as  cobalt and nickel, the cost of lithium iron phosphate batteries is lower. Its  market share has gradually surpassed the ternary lithium battery. The data shows  that China's lithium-ion battery cathode material shipments were 1.094 million  tons, of which lithium iron phosphate cathode materials shipped 455,000 tons and  ternary lithium cathode materials shipped 42.2 tons. Lithium iron phosphate  material has surpassed ternary materials for five consecutive years, becoming  the sub-industry with the largest shipments and the fastest growth rate in the  cathode material segment.

　　In the past, when the cruising range of an electric vehicle was 200  kilometers, the energy density was the most important indicator; but when the  cruising range reached 500 kilometers, it was the same as a tank of fuel for a  fuel vehicle, and the battery energy density was no longer the most important.  Important metrics can become safety, cost, cycle life, etc.

　　The blade battery launched by BYD achieves that the energy density of the  package body is comparable to that of the ternary battery, and the cycle life  and safety factor are stronger, bringing lithium iron phosphate back to the  right path of the industry. Lithium iron phosphate does not contain rare metals,  which better matches the affordability of social resources.

　　SES Power believes that cost is an inescapable proposition. We use lithium  iron phosphate square aluminum shell lithium batteries of 12V100Ah, 12V200Ah,  24V100Ah, 24V200Ah, 36V100Ah, 48V50Ah, 48V100Ah, and the home energy storage  system HESS (3KW inverter output), It was welcomed for its excellent value for  money.

　　For the choice of battery route, the technical route of lithium battery  manufacturers has again differentiated. Stimulated by Tesla's sales, the number  of fans of 4680 large cylindrical batteries is increasing, and the CATL is  launching Kirin batteries to fight back.

　　Safety and economy are the current focus of power batteries. The square  ternary battery is prone to spontaneous combustion due to its high nickel  content. The price of soft-pack ternary batteries with excellent performance is  more expensive than other battery systems. Compared with the two, the large  cylindrical battery has a stable structure in the whole life cycle. During the  battery life cycle, the 46-series large cylindrical battery will not cause  internal stress due to expansion, resulting in changes in the internal structure  of the battery, and will also become the main power source for future high-end  and mid-range vehicles.

　　According to the puncture experiment of EVE Lithium Energy on the large  cylindrical battery, when the puncture experiment was carried out on 6 46 series  batteries, the batteries quickly extinguished after they caught fire. "When the  internal pressure exceeds a certain value, the battery cell will open the valve  to directionally release the main heat enthalpy inside the battery to avoid heat  diffusion between the batteries. The battery has a Vent (vent), which can  quickly release the battery pressure. " Explained the developers.

　　In addition to EVE Lithium Energy, Panasonic Electric and BAK Battery are  also optimistic about the prospects of large cylindrical cells. According to the  data, BAK's large cylindrical battery cells will be mass-produced in 2024, when  the energy density will reach 285Wh/kg.

　　In the face of the menacing large cylindrical batteries, CATL launched the  Kirin battery: under the same chemical system and the same battery pack size,  the 3.0 version CTP power is 13% higher than the 4680 system energy density.

　　According to the information disclosed by CATL, when the Kirin battery  adopts the iron phosphate system, the system energy density is expected to be  160Wh/kg-290Wh/L; when the ternary system is used, the system energy density is  expected to be 250Wh/kg-450Wh/L.

　　Of course, cylindrical batteries also have certain advantages in terms of  power rate output. SES Power's lithium iron phosphate battery capable of rate  discharge at -40℃ is a cylindrical lithium battery with a model of 26650.

　　Against the background of soaring crude oil prices, the substitution effect  of new energy vehicles is also accelerating, which is also an opportunity for  the development of lithium battery manufacturers and new energy vehicle  manufacturers. The technical routes of lithium iron phosphate and ternary  lithium are gradually differentiated. Based on energy density, cost, and safety  considerations, the market share of lithium iron phosphate batteries has  gradually dominated. At this stage, compared with prismatic batteries and pouch  batteries, the market size of large cylindrical batteries is limited, and which  packaging route is dominant also needs to be tested by the market.