Although ternary Nickel Hydride No. 5 batteries technology has difficulties, local companies in my country can also produce it

　　Tesla has once again attracted attention in the past two days. Foreign media reported that Tesla recently provided details of Tesla Model 3’s battery technology in an email to shareholders, including the current raw material ratio used in its batteries.

　　Earlier, Musk claimed that the energy density of the 21700 Nickel Hydride No. 5 batteries that was first used in Model 3 was close to 300 Wh/kg, making it almost the mass-produced lithium-ion battery with the highest energy density in the world. We will wait and see whether Tesla sets another world record.

　　According to a report from Reference News Network on May 14, US media said that in the first quarter of 2018, China contributed about half of the total global sales of new energy vehicles. Tesla claims that its latest battery can be fully charged in 20 minutes and has a range of 350 kilometers. With such a huge market, can China create similar super batteries? The batteries used in my country's new energy vehicles have not yet dominated the world. Is it limited by manufacturing materials or key technologies? Or is it because of choosing a different technical route?

　　There are no limits to the challenge. Chasing energy density ratio is risky.

　　"Tesla claims that the maximum energy density of a battery cell is 300 Wh/kg. The higher the energy density of the battery, the higher the chance of a combustion and explosion accident." Zhang Yu, Secretary General of the Power Battery Application Branch of the China Chemical and Physical Power Supply Industry Association Said that the core of the battery lies in the battery management system. Although Tesla has better solved the thermal runaway problem caused by the increase in energy density through battery system management technology, and has successfully avoided the problem of short cycle life of ternary lithium batteries through car design. problem. However, if the energy density is to be further improved, battery safety management will pose greater challenges.

　　The lithium-ion battery with the highest energy density claimed by Tesla is not perfect in the eyes of industry experts.

　　Yang Yusheng, an academician of the Chinese Academy of Engineering, has emphasized on many occasions that continuously increasing the specific energy of batteries is a very dangerous path.

　　Previously, Wan Gang, chairman of the China Association for Science and Technology, publicly stated that from a market perspective, driving range is indeed an important symbol of the technological progress of electric vehicles, but its realization cannot be solved by simply increasing the amount of on-board batteries.

　　"The greater the energy density of the battery, the greater the amount of electricity stored in the unit volume. The energy density and loading capacity of the battery determine the battery life of the electric vehicle. In the past decade or so, the improvement of battery energy density has mainly relied on the technological progress of the battery material itself. "This can be achieved by increasing the proportion of active materials in the battery," said Yang Xulai, deputy director of the Engineering Research Institute of Hefei Guoxuan Hi-Tech Power Energy Co., Ltd. By increasing the size of the battery and reducing the weight of the casing and other auxiliary materials, the battery energy density can also be achieved. Improved effect.

　　For the new energy industry, which is responsible for the national overtaking mission, the importance of power batteries is self-evident. Many people in the industry admit that power batteries are the heart of new energy vehicles. How far new energy vehicles can go depends mainly on power batteries.

　　It is worth noting that according to the "Made in China 2025" power battery development plan: by 2020, the energy density of domestic batteries will reach 300 Wh/kg. Experts believe that my country is actively promoting the development of high-specific energy batteries, but the relationship between battery safety and specific energy is still worthy of study.

　　Even though there are technical difficulties, local companies can still produce it.

　　Industry experts said that not only Tesla's battery system control capabilities, but also the vehicle design are not something that most Chinese car companies can imitate and surpass in the short term. So, can local Chinese companies create ternary lithium batteries with as strong a range as Tesla?

　　Among the four main materials of the battery - positive electrode material, negative electrode material, electrolyte and separator, the positive electrode material not only accounts for 40% of the cost, but also directly determines the energy density of the battery core. According to the technical route of cathode materials, power batteries can be mainly divided into three categories: lithium iron phosphate, ternary lithium (NCA/NCM) and lithium manganate batteries.

　　According to the composition of the cathode material, ternary lithium batteries are divided into two categories: NCA and NCM. NCM means that the cathode material is composed of three materials: nickel, cobalt and manganese in a certain proportion, while the cathode material of NCA is composed of nickel, cobalt and aluminum. The powerful endurance battery Tesla claims this time is a ternary lithium NCA battery.

　　Zhou Bo, director of the research department of the Power Battery Application Branch of the China Chemical and Physical Power Supply Industry Association, said that NCA’s production process conditions are more stringent and there are thresholds in the production process. More importantly, the technical barriers to NCA materials are also very high. Currently, the production capacity is mainly concentrated in Japan and South Korea, and there is less mass production in my country.

　　"NCA batteries can also be made in China. Last year, a key domestic material company supplied more than 1,000 tons to Japan's Panasonic." Zhang Yu said.

　　However, according to the reporter's understanding, the industrial development of domestic NCA materials and batteries started relatively late. Currently, many companies have begun pilot trials and small batch trial production. There are still some technical problems that need to be solved, and mass production and sales have not yet occurred. At the same time, production materials are limited, and the foreign NCA material market is mainly monopolized by Sumitomo Metal, Nippon Chemical Industry Co., Ltd., etc.

　　Zhang Yu analyzed that the underlying reason why NCA batteries have not been mass-produced in China is that the safety of batteries has declined due to poor thermal stability. Battery manufacturers and end product users are worried about the safety of NCA batteries. This requires system reliable safety design from battery cell design, power supply system design, power supply use and other aspects. From a processing perspective, NCA batteries require a pure oxygen environment and have high processing costs. The humidity must be controlled below 10% during the entire battery production process, which poses great challenges to domestic companies.

　　Based on factors such as technology, cost and subsidies, China has mainly chosen the NCM route, but this does not mean that there are no new opportunities for the NCA route.

　　Cost affects the market, Tesla may not be the benchmark

　　Although local Chinese companies are not unable to produce ternary lithium batteries, Tesla's challenging ternary lithium batteries are not necessarily the only goal of my country's new energy vehicle battery research and production.

　　Data from the Power Battery Application Branch of the China Chemical and Physical Power Sources Industry Association shows that from January to December 2017, the installed capacity of ternary lithium batteries was 16.04 gigawatt-hours, accounting for 44. 01%; the installed capacity of lithium iron phosphate batteries is 17.97 gigawatt hours, accounting for 49.29%; the installed capacity of lithium manganate batteries is 1.48 gigawatt hours, accounting for 4.06%...

　　Industry insiders told reporters that under the guidance of national policies and the support of the market environment, my country's Nickel Hydride No. 5 batteries technology route focuses on both lithium iron phosphate and ternary lithium batteries. However, even in the development of the technical route of ternary lithium batteries, domestic power battery manufacturers also have different priorities. Many choose the NCM route, while few choose the NCA route used by Tesla.

　　NCA batteries have been mass-produced on a large scale and maturely, and have been commercially verified; while NCM batteries with high energy density have not yet been mass-produced on a large scale. Industry experts say that the performance of the two is relatively close, but the high-energy-density NCM is slightly cheaper. Therefore, in terms of cost performance, NCM is more in line with the Chinese market.

　　"In a sense, it is lithium iron phosphate that has made China's new energy vehicles possible. From a cost perspective, lithium iron phosphate has more advantages. We predict that the market space for lithium iron phosphate batteries should be larger than that of ternary lithium batteries in the future. Big. "The development trend of ternary lithium batteries at this stage benefits from the national policy-oriented requirements for high-specific energy batteries, which require high energy density and long cruising range. Of course, ternary lithium batteries have higher specific energy and specific power and are more in line with the needs of passenger cars, but they may not necessarily become the mainstream of the market in the future.

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