Recently, news that CATL plans to mass-produce NCM811 power batteries next year has put a new round of technology competition in the power battery industry before people's eyes. Earlier, BYD also stated in an unofficial public statement that its NCM811 power battery will be put into use in the second half of 2019.

　　Recently, news that CATL plans to mass-produce NCM811 power batteries next year has put a new round of technology competition in the power battery industry before people's eyes. Earlier, BYD also stated in an unofficial public statement that its NCM811 power battery will be put into use in the second half of 2019.

　　NCM811, a ternary lithium battery with a nickel-cobalt-manganese content ratio of 80%:10%:10% in the cathode material, represents the route with the highest energy density and highest technological content in the current power battery field.

　　However, in the current context, the two major power battery leaders have both announced that they will launch NCM811, but the core intention is not to fight to the death at this time.

　　Two years later, after the decline of domestic new energy vehicles and the liberalization of the power battery industry, foreign-funded batteries that are leading in technology and industrial layout will truly make a comeback. By then, there may be a more tragic Three Kingdoms Killing of power batteries. The most effective way for domestic power battery companies to respond is to respond to challenges with advanced technology.

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　　High-nickel material system becomes the only way for power batteries

　　If in 2017, power battery companies still had doubts about the selection of cathode materials for ternary lithium batteries, then one year later, two powerful forces: the price of cobalt, and the energy density requirements put forward by policies and markets, basically The company's choice is locked in high-nickel ternary materials.

　　According to data from the London Precious Metals Exchange in February this year, in the 18 months since then, the price of cobalt, a particularly critical material in power batteries, has tripled, with the highest price reaching US$80,000 per day. Ton. According to the financial report of Jinchuan International, the world's fourth largest cobalt producer, its average cobalt selling price rose to US$74,243 per ton in the first half of the year, a year-on-year increase of 118%. In the past two days, the price of cobalt (electrolytic cobalt) has fallen slightly below 500,000 yuan/ton. However, the price of one ton of electrolytic nickel is currently just over 110,000.

　　Cathode materials account for the highest cost of power batteries, up to 30%. Comparing the soaring cobalt prices with the relatively low nickel prices, power battery companies have decided to pick nickel. This is the first factor in the rise of high-nickel ternary materials.

　　At the same time, range anxiety for electric vehicles is still widespread today. The recent news that NIO ES8 has a cruising range of over 200 kilometers at a speed of 120 kilometers per hour has attracted widespread attention, which is the best example. Consumer expectations for the cruising range of electric vehicles are transmitted to power battery companies through car manufacturers, which inevitably require batteries with higher energy density, greater charge, and the ability to run farther.

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　　It just so happens that the main role of nickel in lithium-ion batteries is to increase the gram capacity and make the energy density of the battery higher. Public data shows that the gram capacity of NCM811 material can reach 190mAh/g, which is significantly higher than NCM523, which has higher cobalt content and is currently the most mainstream in China.

　　Similarly, national policies are also strengthening the requirements for the energy density and cost of power batteries. The "Action Plan to Promote the Development of the Automotive Power Battery Industry" issued in February 2017 clearly states that by 2020, the energy density of a power battery cell will be 300Wh/kg, the system energy density will be 260Wh/kg, and the cost will be 1 yuan/Wh. New energy vehicle subsidy standards that continue to rise. For example, this year, pure electric passenger vehicles require a system energy density of 140Wh/kg to receive full subsidies. This is also pushing the power battery industry to move towards high-nickel ternary materials.

　　In 2018, NCM811 became the darling of the domestic power battery industry. Not only BYD and CATL have expressed plans for mass production in 2019, but Guoxuan Hi-Tech and Yiwei Lithium Energy also plan to mass produce in 2019. BAK, Lishen, and Penghui New Energy have even stated that their NCM811 power batteries have already Achieved mass production and supply. Among them, BAK also listed a customer list, including BAIC New Energy, SAIC Maxus, Yundu, etc. NCM622, which was originally planned to be developed and promoted based on NCM523, has become less popular at this time.

　　With the joint efforts of many parties, China's power battery technology seems to be ushering in another round of "one step" leapfrog development.

　　Battle for high-nickel power batteries: Japan leads, domestic production has fallen behind

　　However, when the NCM811 trend was blowing in China's power battery industry, "bad news" came from South Korea:

　　Last year, SKI, the third largest company in South Korea's power battery industry, announced the mass production of NCM811 soft-pack power batteries and will supply Kia's electric vehicles. However, this year, SKI announced that it would postpone the mass production of NCM811.

　　As for LG, another power battery giant in South Korea, when the Hyundai KonaEV equipped with LG batteries was unveiled at the beginning of this year, it was once rumored to be "the first electric vehicle to use NCM811 batteries." However, the Korean media later refuted the rumors and said that the KonaEV uses NCM622 ternary batteries. Battery. LG Chem’s CFO also stated in an interview that the NCM811 produced by LG is limited to cylindrical lithium batteries and is only used in electric buses.

　　However, domestic manufacturers have not yet achieved large-scale production of the NCM622 technology route, which has slightly lower technical requirements. In terms of future-oriented technology reserves, the domestic power battery industry is the weakest among China, Japan and South Korea.

　　There has always been a mutually restrictive relationship between the various attributes of ternary lithium power batteries - the higher the energy density, the more difficult it is to ensure temperature control and safety; to ensure the battery cycle life, the energy density will be relatively limited.

　　▲The relationship between the nickel content in the ternary material and the battery properties: the left side is the runaway temperature, the middle side is the gram capacity, and the right side is the capacity retention performance

　　The proportion of nickel in NCM811 is increased, which increases the energy density of the battery. However, it has to pay many costs such as reduced battery cycle life, poor thermal stability of the battery, and reduced power performance. This requires the use of other key materials in the power battery. (Anode material, separator, electrolyte) and the links of battery core groups and systems should be repaired.

　　Only Japan's Panasonic has truly solved the problem of mass production and application of high-nickel ternary material power batteries in the form of cylindrical batteries. Although the cathode material used by Panasonic is NCA (nickel cobalt aluminum), and the ratio of the three materials is 80%:15%:5%, it is essentially the same as the NCM811 route. On the 21700 cylindrical battery used in Tesla Model 3, Panasonic achieved the single cell energy density target of 300Wh/kg.

　　▲2170 battery cells used by Tesla

　　The ultra-high energy density of the batteries offered by Panasonic is not solely due to the high-nickel cathode material. On the negative electrode, Panasonic uses carbon silicon material. The gram capacity of silicon is 4200mah/g, while the gram capacity of pure graphite anode is only 373mah/g. The gram capacity of carbon-silicon anode material mixed with silicon can reach the level of 400-650mah/g, further increasing the energy density of the battery. .

　　Tesla previously pointed out in its production report that some of its battery performance indicators are already stronger than those of its competitors' next-generation batteries. Compared with CATL's roadmap, this seems to be the case.

　　Looking at the technology roadmap of CATL, they use NCM811 with carbon-silicon anode to achieve an energy density of 300Wh/kg, which will only be launched in 2020.

　　This means that Panasonic is at least 2-3 years ahead of China's leading power battery companies in the industrialization and application of high-nickel ternary lithium power batteries to passenger cars. Although CATL and BYD ranked first and third in power battery shipments last year, Panasonic is still recognized as the number one in terms of technology.

　　Although many domestic power battery companies have launched NCM811 cylindrical lithium batteries and begun to market them, they are completely unable to compare with Panasonic's supply of several GWh in scale.

　　Mass production of high-nickel batteries requires industry-wide progress

　　Previously, Che Dongxi appeared in "One Girl Marries Multiple!" According to analysis in "Behind the Global Car Companies' Grabbing CATL", CATL's frequent joint ventures with car manufacturers are mostly due to the fact that its technological depth is not as advanced as that of foreign giants, and it hopes to use this move to bind car companies. Share the risk. BYD has also recently entered into a joint venture with Changan in the power battery field.

　　However, the lack of technological dominance is not entirely due to the lack of hard work of CATL and BYD. Due to the nature of power batteries that can affect the whole body, the application of NCM811 actually requires the full cooperation of the entire industry system. The upstream and downstream of domestic power battery manufacturers, China's power battery industry and even the new energy vehicle industry are already in the role of catch-up.

　　In the upstream of the entire industry, Japanese and Korean companies currently dominate the technology for the four key materials of power batteries (positive electrode materials, negative electrode materials, separators, and electrolytes), especially for more cutting-edge high-nickel ternary materials and their supporting materials.

　　1. Cathode material

　　In terms of cathode materials, the mature preparation technology and mass production capabilities of high-nickel ternary materials are currently mainly in the hands of Japan's Sumitomo, Toda Industries and South Korea's ECOPRO. High-nickel ternary materials also rely heavily on imports.

　　▲Ternary materials under the electron microscope

　　According to statistics from the CBC Nonferrous Network, my country imported a total of 9,142 tons of ternary materials in 2017, a significant increase of 288.5% year-on-year.

　　2. Negative electrode material

　　In terms of anode materials, the domestic power battery industry is also lagging behind in the production and application of carbon-silicon anodes. According to data from Qidian Research Institute, China's output of silicon-carbon anode materials for lithium batteries reached 1,500 tons in 2017. Although the growth rate reached 130%, it only accounted for 1% of the total output of lithium battery anode materials throughout the year.

　　In Japan, Panasonic used carbon-silicon anodes in the NCR18650C model battery released in 2012, and carbon-silicon anodes were used in subsequent Tesla power batteries. This means that Japan’s carbon-silicon anode materials have begun large-scale industrial application since 2012.

　　3. Electrolyte

　　In terms of electrolyte, the NMC811 power battery has a higher chemically active nickel content, which is more likely to react with the electrolyte. First, it will cause surface oxidation of the positive electrode material. Second, it will cause the electrolyte to decompose and produce gas, affecting the energy of the battery. , safety performance. At this time, it is necessary to develop an electrolyte with more stable chemical properties that matches the NCM811 material.

　　Similarly, my country's electrolyte industry started later than Japan and South Korea. Although it captured 70% of the global electrolyte market share in 2017, Chinese companies are making slower progress than Japan, South Korea, especially Japan, in the new generation of electrolytes that are matched with high-nickel ternary materials. Currently, the electrolyte in Tesla's NCA power battery, which represents the highest strength, comes from Japan's Mitsubishi Chemical, which has 20 years of production experience. Domestic manufacturers are generally still in the stage of technological research. At present, only domestic electrolyte giant Xinzhoubang has publicly announced mass production of electrolytes matching NCM811 cathode materials.

　　4. Battery separator

　　Regarding the separator with the highest technical content, the high nickel and high energy density of power batteries require two major improvements in separator technology - first, the production method is changed from dry to wet, so as to obtain better charging rate and energy. Density performance; second, the film material has evolved from PP/PE to ceramic materials, thereby obtaining better safety performance and energy density performance.

　　▲Diaphragm production line

　　According to 2015 data, the world's top three lithium-ion battery separator manufacturers are Japan's Asahi Kasei, Tonen Chemical, and South Korea's SKI. The top six overseas companies have a total market share of 72%. In 2016, the total demand for lithium battery separators in the Chinese market reached 2 billion square meters, accounting for nearly 60% of the global market. However, the output of domestic separators was only about 1.2 billion square meters, and the import rate of separators reached 40%. Although domestic separator manufacturers have continued to increase their market share in the past two years, they are still in the embarrassing situation of overcapacity in low-end dry process separators and insufficient production capacity in high-end wet process separators.

　　In the middle reaches of the industry, on the side of power battery manufacturers, the domestic choice of power battery packaging routes has also brought a test to the mass production of NCM811 power batteries.

　　Panasonic uses a cylindrical lithium battery packaging route, which has a relatively hard shell and a small single cell. The advantage of this is that the high-hardness shell can better suppress the volume expansion of the carbon-silicon anode and the production of gas in the battery. The problem. At the same time, the thermal runaway problem of a single smaller cylindrical battery is better managed and less likely to spread. As power batteries move toward high-nickel ternary batteries, safety issues have become most acute, and the shape of cylindrical lithium batteries has better alleviated this problem.

　　Domestic power battery manufacturers, led by CATL and BYD, mostly choose the square hard-shell packaging route. The advantages in ensuring safety are not as obvious as cylindrical batteries. Square hard-shell NCM811 power batteries have not yet become popular in the world. Cases of large-scale application, no experience to follow

　　In addition, the battery core consistency of domestic power battery manufacturers also lags behind that of Japanese and Korean companies.

　　In the downstream industry, the ability of car companies to carry out supporting applications for power batteries is also a difficulty hindering the popularization of NCM811. Still taking Panasonic's power battery as an example, Panasonic and Tesla are actually in a mutually beneficial relationship.

　　Although Panasonic has provided Tesla with 21700NCA batteries with a single energy density of 300Wh/kg, in fact, Panasonic has not completely solved the negative impact of high nickel and carbon-silicon anodes, and the cycle life of its batteries has not been It has reached the current level of 2000+ times for mainstream ternary material batteries.

　　However, Tesla has extended the service life of the power battery in disguise by increasing the battery system capacity to 100KWh and reducing the single discharge depth of a single cell. At the same time, Tesla’s battery liquid cooling system and BMS, which can manage 7,000 battery cells, are also ensuring the normal operation of the battery.

　　The ability of domestic car companies to conduct in-depth cooperation with power battery manufacturers to create a deeply customized battery management system to deeply optimize battery working conditions has yet to be verified.

　　In addition, there are still problems in the domestic power battery industry that need to be solved, such as reliance on imported production equipment and the inability to reuse the original production lines to transition to NCM811 production.

　　Foreign giants are eyeing domestic companies to catch up quickly

　　Judging from the current industry situation, for the next generation of high-nickel ternary power batteries, Japan is currently in a leading position in technology and application due to the radical multinational combination of Panasonic-Tesla and the strong and complete industrial chain support behind it. All are in a leading position.

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