Selection and technical research of positive and negative materials for power lithium batteries -Lithium - Ion Battery Equipment
"Higher, faster, stronger" is the familiar spirit of Olympic competition. This motto of the Olympic movement was proposed by Coubertin, the founder of the modern Olympic movement, and elaborates on the Olympic movement's spirit of continuous improvement and never-satisfied struggle.
Switching to the electric vehicle industry, as the power lithium battery at its heart, in terms of battery material selection and technical research, developing new technologies to supply higher energy density and achieve longer cruising range is currently a challenge faced by the industry. Challenges and research hotspots.
According to Fang Kaizheng, an expert at the Power Lithium Battery Research Office of the Beijing Office of my country Automotive Research Center, the increase in the production of new energy vehicles has driven the rise of power lithium battery supporting batteries. In the first three quarters, the total supply of power lithium batteries exceeded 12.1 billion watt-hours. , of which the supporting volume for pure electric vehicles is 11 billion watt-hours, and the supporting volume for plug-in hybrid vehicles is 1.1 billion watt-hours. Riding on the development trend of the power lithium battery industry, industry researchers are also constantly studying the technology research and development path to improve the energy density of power lithium batteries and achieve their development goals of "higher energy density, stronger power, and longer range".(Lithium - Ion Battery Equipment)
Diversification of technical routes
Tan Xinxin, deputy director of the research institute of Hunan Shanshan Energy Technology Co., Ltd., said that as an important raw material supplier in the battery field, Shanshan will consider continuously improving the discharge specific capacity and charge and discharge voltage of battery materials, and will also consider its power. Density and calendar life, including cycling, side reactions, etc.
In terms of material selection, high-nickel ternary materials have become a popular choice in the industry. Because it has greater advantages in specific energy than lithium iron phosphate and low-nickel ternary materials. The company's investment in related technology research and development has also followed suit.
If you want to increase the energy density of the battery, when selecting materials, President Tan Xinxin of Hunan Shanshan Research Institute pointed out: "A high-performance power ternary material does not simply highlight one or two series. , if there is a series that cannot do it, I think it is definitely not a good cathode material."
He also mentioned four related possible technology research and development routes. The first is the most well-known and widely used nickel content improvement route; the second is the medium-nickel high-voltage development route; the third is the high-nickel and high-voltage development route; and the fourth is the high-voltage LCO development route. From the perspective of energy density, as the nickel content increases, the overall energy density of the battery will become higher and higher, and the increase in power will also bring about improvements. At the same time, high-voltage lithium cobalt oxide has a voltage platform and high capacity, and the overall energy density It will also be higher.
However, when everyone is talking about high nickel capacity reaching 300Wh/kg or even 400Wh/kg, Tan Xinxin also mentioned that as far as the current situation is concerned, high-nickel materials, especially materials with a nickel content of more than 80%, will not be as popular in the entire domestic market this year. The proportion of high-energy-density cathode materials is less than 1%. It may take some time to promote and use high-energy-density cathode materials in China, and the entire industry must prevent excessive hype and local overheating.
High nickel content of cathode material
In terms of the development trend of power lithium batteries, there are basically three categories of positive electrode materials. The negative electrode materials are mainly carbon materials. Silicon carbon materials and hot materials are also being studied. Among them, lithium titanate is an important material choice for oxides. .
"Cathode materials will gradually transition to ternary materials," Chen Yanbin, general manager of Dangsheng Technology, believes. Dangsheng Technology has always been at the forefront of the industry in the research and development of high energy density ternary materials. It is a feasible technical route to continuously increase the energy density of batteries by increasing the content of nickel materials. But which specific technical route to take, such as whether to go high nickel or high voltage first, may vary from company to company.
Chen Yanbin explained: "Looking at the overall international trend, the route taken is to increase power consumption first and then develop high voltage."
Nowadays, high-energy-density cathode materials are increasingly becoming the mainstream of development in the battery industry. It is reported that domestic cathode material production companies with leading product technology have begun to research and produce high-nickel ternary materials. Certain types of high-nickel ternary materials , for example, Type 622 and Type 811 have also begun small batch production, and some companies have already carried out experimental applications in downstream companies. Moreover, the capacity ratios of Type 622 and Type 811 can reach 160mAh/g and 180mAh/g respectively, which is improved to a certain extent compared with the current Type 532 and Type 111.
Chen Yanbin also mentioned that high nickel phase is still the preferred direction for high voltage. The ultimate goal of high-nickel materials is type 811, and type 811 materials are also more promising. Dangsheng Technology adopts the high-nickel route for high energy density, and also produces some high-voltage products with medium and high nickel. At the same time, it also improves the life and safety of batteries from aspects such as precursor, sintering, doping, and surface treatment.
To make high-nickel materials, we must solve the problems of life span, storage safety and other aspects, and optimize all aspects of precursor, deliquescence, doping and surface. Regarding whether there is a problem with the life of high nickel, Chen Yanbin also said that the research and development technology of Dangsheng Technology can ensure that the life will not be affected on the basis of increasing the capacity by 20 mAh.
Increase research and development of negative electrode materials
By 2025, how will power lithium batteries achieve high energy density and fast charging? In the field of fast-charging anode materials, Betri has been developing a composite high-energy-density anode material. Through close cooperation between battery manufacturers and vehicle manufacturers, it has achieved a battery energy ratio of 300Wh/kg and a vehicle cruising range of 500 kilometers. , Yan Huiqing, technical director of Beterui, answered this way.
Yan Huiqing also said that Beterui has carried out technological development on four negative electrode materials, namely fast-charging graphite negative electrode materials, fast-charging soft carbon/hard carbon materials, fast-charging silicon series materials, and fast-charging lithium carbonate negative electrode materials.
At present, the batteries developed by domestic battery companies are basically based on lithium iron phosphate batteries, which are widely used in passenger cars, special vehicles, buses, etc. Yan Huiqing said: "To improve the energy density of lithium iron phosphate, we must first make a good negative electrode. We have been continuously developing negative electrode materials and making high-energy-density lithium iron phosphate batteries. From the perspective of the processing of the powder itself, the positive electrode and negative electrode Or ternary materials, which have similar technologies in improving the overall compaction density and capacity of the battery, so we are also developing high-energy-density lithium iron phosphate batteries and working hard to increase the battery capacity and compaction density. Especially the compaction density, so we made spherical lithium iron phosphate. At the same time, we applied high-end anode materials to it to increase the energy density of the entire lithium iron phosphate battery."
In contrast, Lu Xuelong, a senior researcher at the Materials Research Department of the Industrial Technology Research Institute, believes: "In fact, last year, some battery manufacturers began to mention the use of ternary materials as a component. The second option is to use lithium iron phosphate directly as a component. A solution for cathode materials to increase energy density. Other academic research units, such as Harbin Institute of Technology, also have technologies that include lithium vanadium phosphate. The difference is that it seems that for cathode material manufacturers, the solution to lithium vanadium phosphate is not yet effective at this stage. Methods."
Nowadays, the requirements for the cruising range of electric vehicles are getting higher and higher. As for power lithium batteries, if its energy density is now required to be doubled, its technical difficulties exist in many aspects.
Su Jinran, deputy chief engineer of Tianjin Lishen Battery Co., Ltd. (referred to as "Lishen") analyzed that under the current lithium-ion system, it does take some effort to reach 350 Wh/kg. Current NCA, nickel materials, silicon-carbon anode materials and other aspects still need to be discussed. However, the actual use of silicon-carbon anode materials in power lithium batteries still requires overcoming some technical problems, such as its cycle characteristics, expansion characteristics, etc.
Therefore, some in-depth research should be done on some new power lithium battery cathode materials, anode materials and even separator materials. If there are no breakthroughs in these aspects, the improvement of technological level may be limited. Lishen also has a dedicated team doing this work.
From the perspective of battery material system, Xiao Chengwei, director of the 18th Institute of my country Electronics Technology Group Corporation, said that battery negative electrode materials are basically carbon-based, and positive electrode materials will also undergo major changes, including lithium manganate, lithium cobalt oxide and other materials. .
From the perspective of the entire development industry trend, we hope to develop hybrid lithium batteries with increasingly higher industrial energy density through the selection of different material systems to achieve large-scale application in the field of new energy vehicles.
However, Xiao Chengwei analyzed that judging from some of the technology development roadmaps and next-step subsidy policies promulgated by the country, the country is still providing some guidance in the direction of high-specific energy batteries. While various battery companies are trying to increase the energy density of lithium iron phosphate batteries as much as possible, they will also increase their efforts to develop and promote some products of ternary batteries in the next step.
Power lithium battery research and development technology is an important factor affecting the promotion and application of electric vehicles. As one of the important indicators of power lithium battery performance, increasing energy density is only one of the methods. The entire power lithium battery industry must also reduce costs and improve the overall performance of power lithium batteries by increasing power density, service life, and developing new material technologies. performance.
Switching to the electric vehicle industry, as the power lithium battery at its heart, in terms of battery material selection and technical research, developing new technologies to supply higher energy density and achieve longer cruising range is currently a challenge faced by the industry. Challenges and research hotspots.
According to Fang Kaizheng, an expert at the Power Lithium Battery Research Office of the Beijing Office of my country Automotive Research Center, the increase in the production of new energy vehicles has driven the rise of power lithium battery supporting batteries. In the first three quarters, the total supply of power lithium batteries exceeded 12.1 billion watt-hours. , of which the supporting volume for pure electric vehicles is 11 billion watt-hours, and the supporting volume for plug-in hybrid vehicles is 1.1 billion watt-hours. Riding on the development trend of the power lithium battery industry, industry researchers are also constantly studying the technology research and development path to improve the energy density of power lithium batteries and achieve their development goals of "higher energy density, stronger power, and longer range".(Lithium - Ion Battery Equipment)
Diversification of technical routes
Tan Xinxin, deputy director of the research institute of Hunan Shanshan Energy Technology Co., Ltd., said that as an important raw material supplier in the battery field, Shanshan will consider continuously improving the discharge specific capacity and charge and discharge voltage of battery materials, and will also consider its power. Density and calendar life, including cycling, side reactions, etc.
In terms of material selection, high-nickel ternary materials have become a popular choice in the industry. Because it has greater advantages in specific energy than lithium iron phosphate and low-nickel ternary materials. The company's investment in related technology research and development has also followed suit.
If you want to increase the energy density of the battery, when selecting materials, President Tan Xinxin of Hunan Shanshan Research Institute pointed out: "A high-performance power ternary material does not simply highlight one or two series. , if there is a series that cannot do it, I think it is definitely not a good cathode material."
He also mentioned four related possible technology research and development routes. The first is the most well-known and widely used nickel content improvement route; the second is the medium-nickel high-voltage development route; the third is the high-nickel and high-voltage development route; and the fourth is the high-voltage LCO development route. From the perspective of energy density, as the nickel content increases, the overall energy density of the battery will become higher and higher, and the increase in power will also bring about improvements. At the same time, high-voltage lithium cobalt oxide has a voltage platform and high capacity, and the overall energy density It will also be higher.
However, when everyone is talking about high nickel capacity reaching 300Wh/kg or even 400Wh/kg, Tan Xinxin also mentioned that as far as the current situation is concerned, high-nickel materials, especially materials with a nickel content of more than 80%, will not be as popular in the entire domestic market this year. The proportion of high-energy-density cathode materials is less than 1%. It may take some time to promote and use high-energy-density cathode materials in China, and the entire industry must prevent excessive hype and local overheating.
High nickel content of cathode material
In terms of the development trend of power lithium batteries, there are basically three categories of positive electrode materials. The negative electrode materials are mainly carbon materials. Silicon carbon materials and hot materials are also being studied. Among them, lithium titanate is an important material choice for oxides. .
"Cathode materials will gradually transition to ternary materials," Chen Yanbin, general manager of Dangsheng Technology, believes. Dangsheng Technology has always been at the forefront of the industry in the research and development of high energy density ternary materials. It is a feasible technical route to continuously increase the energy density of batteries by increasing the content of nickel materials. But which specific technical route to take, such as whether to go high nickel or high voltage first, may vary from company to company.
Chen Yanbin explained: "Looking at the overall international trend, the route taken is to increase power consumption first and then develop high voltage."
Nowadays, high-energy-density cathode materials are increasingly becoming the mainstream of development in the battery industry. It is reported that domestic cathode material production companies with leading product technology have begun to research and produce high-nickel ternary materials. Certain types of high-nickel ternary materials , for example, Type 622 and Type 811 have also begun small batch production, and some companies have already carried out experimental applications in downstream companies. Moreover, the capacity ratios of Type 622 and Type 811 can reach 160mAh/g and 180mAh/g respectively, which is improved to a certain extent compared with the current Type 532 and Type 111.
Chen Yanbin also mentioned that high nickel phase is still the preferred direction for high voltage. The ultimate goal of high-nickel materials is type 811, and type 811 materials are also more promising. Dangsheng Technology adopts the high-nickel route for high energy density, and also produces some high-voltage products with medium and high nickel. At the same time, it also improves the life and safety of batteries from aspects such as precursor, sintering, doping, and surface treatment.
To make high-nickel materials, we must solve the problems of life span, storage safety and other aspects, and optimize all aspects of precursor, deliquescence, doping and surface. Regarding whether there is a problem with the life of high nickel, Chen Yanbin also said that the research and development technology of Dangsheng Technology can ensure that the life will not be affected on the basis of increasing the capacity by 20 mAh.
Increase research and development of negative electrode materials
By 2025, how will power lithium batteries achieve high energy density and fast charging? In the field of fast-charging anode materials, Betri has been developing a composite high-energy-density anode material. Through close cooperation between battery manufacturers and vehicle manufacturers, it has achieved a battery energy ratio of 300Wh/kg and a vehicle cruising range of 500 kilometers. , Yan Huiqing, technical director of Beterui, answered this way.
Yan Huiqing also said that Beterui has carried out technological development on four negative electrode materials, namely fast-charging graphite negative electrode materials, fast-charging soft carbon/hard carbon materials, fast-charging silicon series materials, and fast-charging lithium carbonate negative electrode materials.
At present, the batteries developed by domestic battery companies are basically based on lithium iron phosphate batteries, which are widely used in passenger cars, special vehicles, buses, etc. Yan Huiqing said: "To improve the energy density of lithium iron phosphate, we must first make a good negative electrode. We have been continuously developing negative electrode materials and making high-energy-density lithium iron phosphate batteries. From the perspective of the processing of the powder itself, the positive electrode and negative electrode Or ternary materials, which have similar technologies in improving the overall compaction density and capacity of the battery, so we are also developing high-energy-density lithium iron phosphate batteries and working hard to increase the battery capacity and compaction density. Especially the compaction density, so we made spherical lithium iron phosphate. At the same time, we applied high-end anode materials to it to increase the energy density of the entire lithium iron phosphate battery."
In contrast, Lu Xuelong, a senior researcher at the Materials Research Department of the Industrial Technology Research Institute, believes: "In fact, last year, some battery manufacturers began to mention the use of ternary materials as a component. The second option is to use lithium iron phosphate directly as a component. A solution for cathode materials to increase energy density. Other academic research units, such as Harbin Institute of Technology, also have technologies that include lithium vanadium phosphate. The difference is that it seems that for cathode material manufacturers, the solution to lithium vanadium phosphate is not yet effective at this stage. Methods."
Nowadays, the requirements for the cruising range of electric vehicles are getting higher and higher. As for power lithium batteries, if its energy density is now required to be doubled, its technical difficulties exist in many aspects.
Su Jinran, deputy chief engineer of Tianjin Lishen Battery Co., Ltd. (referred to as "Lishen") analyzed that under the current lithium-ion system, it does take some effort to reach 350 Wh/kg. Current NCA, nickel materials, silicon-carbon anode materials and other aspects still need to be discussed. However, the actual use of silicon-carbon anode materials in power lithium batteries still requires overcoming some technical problems, such as its cycle characteristics, expansion characteristics, etc.
Therefore, some in-depth research should be done on some new power lithium battery cathode materials, anode materials and even separator materials. If there are no breakthroughs in these aspects, the improvement of technological level may be limited. Lishen also has a dedicated team doing this work.
From the perspective of battery material system, Xiao Chengwei, director of the 18th Institute of my country Electronics Technology Group Corporation, said that battery negative electrode materials are basically carbon-based, and positive electrode materials will also undergo major changes, including lithium manganate, lithium cobalt oxide and other materials. .
From the perspective of the entire development industry trend, we hope to develop hybrid lithium batteries with increasingly higher industrial energy density through the selection of different material systems to achieve large-scale application in the field of new energy vehicles.
However, Xiao Chengwei analyzed that judging from some of the technology development roadmaps and next-step subsidy policies promulgated by the country, the country is still providing some guidance in the direction of high-specific energy batteries. While various battery companies are trying to increase the energy density of lithium iron phosphate batteries as much as possible, they will also increase their efforts to develop and promote some products of ternary batteries in the next step.
Power lithium battery research and development technology is an important factor affecting the promotion and application of electric vehicles. As one of the important indicators of power lithium battery performance, increasing energy density is only one of the methods. The entire power lithium battery industry must also reduce costs and improve the overall performance of power lithium batteries by increasing power density, service life, and developing new material technologies. performance.
