"With a range of 1000 kilometers and an 80% charge in 8 minutes", the graphene battery seems to light up the future of new energy vehicles at once, but the controversy surrounding it also continues to ripple.

"If someone says that his car can run a thousand kilometers, charge it up in a few minutes, is extremely safe, and the cost is very low, then you should not believe him, because it is impossible to achieve these things at the same time," Ouyang Minggao, an academician at the Chinese Academy of Sciences and vice chairman of China's 100 Association of Electric Vehicles, said on Jan. 16.

And just a day ago, GAC AIAN announced "8 minutes charge 80%, the use of silicon anode material graphene-based super fast rechargeable battery", NEDC range can reach 1000 kilometers. Not only that, NIO, SAIC Zhiji and others also announced that they would launch a 1000km range of pure electric vehicles at the same time.

For a time, the power technology route of new energy vehicles has once again become a hot topic in the industry, and the technological war of new energy vehicles in 2021 has been opened. Clearly, long battery life is the theme of this battle.

According to GAC Group, the graphene-based super fast rechargeable battery and the long-endurance silicon negative battery are expected to be installed in AIONV and AIONLX models respectively this year. File photo /ICphoto

Graphene batteries, which claim to be fast charging and have a long battery life, are controversial

Higher demands for range, safety and other aspects are driving the industry to develop a new generation of batteries. Just as Huang Xuejie of the Institute of Physics of the Chinese Academy of Sciences said, "a generation of cathode materials, a generation of power lithium ion battery", the industry believes that the most key to the development of a new generation of power lithium ion battery is the upgrade of materials.

In 2015, the Fuqiang Huang research team at the Shanghai Institute of Ceramics of the Chinese Academy of Sciences found that graphene has the best electrochemical energy storage properties and can be used as a "super strong battery" for electric vehicles, with a range of 35 kilometers after a seven-second charge. At that time, there was a view that if the technology could reach mass production, it would break the technological bottleneck of new energy. Samsung filed a patent for graphene batteries in 2017, but has yet to produce a single graphene battery in mass production.

Recently, GAC Group once again heated up the concept of graphene battery. Zeng Qinghong, chairman of GAC Group, said recently that GAC's graphene-based super fast rechargeable battery has entered the mass production test stage. The first model carrying the battery is AIONV, which is currently undergoing winter test in Heihe and is initially scheduled for mass production in September this year. Zeng Qinghong said that the graphene quick-rechargeable battery can be charged to 80% in the fastest 8 minutes, and GAC's current graphene preparation technology can reduce the production cost by more than 90%.

GAC Graphene battery quickly caused a hot debate. Some people believe that graphene batteries can improve the charge and discharge rate, and the new energy vehicle's range problem has the final answer; But there are also views that there is no real graphene battery at this stage, GAC graphene battery gimmick composition is relatively large.

Ouyang Minggao, for one, thinks it is impossible to produce a safe and cheap electric car with a range of 1,000 kilometers and a few minutes of charging.

At present, the application of graphene in power lithium-ion batteries is important in two directions: one is as a conductive agent; the other is as an electrode material. Graphene can improve the conductivity of batteries, theoretically achieving short time of charging and long range; But costs cannot be controlled.

Wang Zidong, deputy secretary general of China Automotive Power Lithium-ion Battery Industry Innovation Alliance, said, "Theoretically graphene is helpful to improve the battery charge and discharge rate, but not much to improve the performance." Zhang Xiang, an automotive industry analyst, said, "Graphene batteries are only at the laboratory stage, the technology is not mature, and the possibility of mass production in a short time is not great."

Zeng Qinghong has said that GAC Group is on the basis of 811 and 622 ternary lithium-ion batteries by adding 1%-2% graphene anode and cathode materials to improve the battery charging speed, energy density and endurance. According to Zeng Qinghong's previous statement, GAC Aian's graphene-based super fast rechargeable battery is not based on graphene.

In the face of doubts, GAC's general manager Gu Huinan responded to the media that "this year's 1,000km range (electric vehicles) will definitely come out, and it is theoretically possible to charge 1,000km in 8 minutes, but the battery can bear it but the problem of supporting charging pile should be solved". On January 18th, the gac group again responded that graphene based super quick charge battery with long range of silicon anode cell is two different techniques, respectively, to solve "slow charge" and "short range of these two power lithium ion battery application of different pain points, is expected to carry respectively within this year in guangzhou Mr Abe AIONV existing and AIONLX models, Market demand is uncertain.

A charging pile industry insider told the Beijing News: "A battery with a range of 1,000 kilometers has a capacity of 150kWh, and the capacity of the battery needs to reach 120kWh if it is charged to 80%. According to the statement of charging 80% in eight minutes, the power of the charging pile needs to reach 900kW/h, and it needs to be equipped with a transformer of more than 1200kVA, which is impossible to achieve."

Ouyang Minggao admitted, "Recently, there will be a lot of announcements about battery innovation, which is normal business operation. Of course, we should not overdo it, and then it will become hype." Wang Binggang, director of the technical committee of the National Electric Passenger Car Technology Innovation Alliance, believes that the power lithium-ion battery should comprehensively consider the weight of the vehicle, charging safety, damage to the battery and cost performance and other issues, and can not only talk about theory.

Rising energy demand is driving the evolution of power lithium-ion battery technology

"While a 1,000km range is not what we are looking for, the energy demand of electric vehicles is definitely going up." Ouyang Minggao said.

From the appearance of the first lead-acid battery electric vehicle in 1881 to today's long-endurance electric vehicle and hydrogen fuel powered lithium-ion battery vehicle, the driving factor for the development of powered lithium-ion battery has always been the "rising energy demand for electric vehicles".

After the first electric cars were introduced, 38 per cent of car sales in the US and Europe were electric. Lead-acid batteries have many disadvantages, such as heavy weight, short life, high cost and short battery life. As a result, the lead-acid battery electric car was temporarily withdrawn from the market after the internal combustion engine made significant progress.

In the 1990s, nickel-metal hydride batteries came onto the scene, with vastly improved energy density and power. Panasonic is a well-known developer of nickel-metal hydride batteries in the industry. In 2012, mass production proved the effectiveness and safety of nickel-metal hydride batteries, and electric vehicles using nickel-metal hydride batteries once occupied more than 80% of the market share. However, there are a number of constraints in the practical application of nickel metal hydride batteries, including high temperature performance, storage performance, cycle life, thermal management and price.

With the development of power lithium-ion battery technology, the lithium-ion battery with significantly improved energy density and further reduced cost began to appear and gradually became the mainstream.

"When ternary lithium-ion batteries were not industrialized, lithium-ion iron phosphate batteries were used more, but their range was lower." Ouyang Minggao said, "Later, the three yuan lithium-ion battery with high volume and energy density began to industrialize, and the energy of on-board batteries increased significantly, and the range increased, and the electric car market began to start."

Chen Liquan, from the Institute of Physics of the Chinese Academy of Sciences, said that from the market situation, the current mainstream power lithium ion battery is shifting from lithium iron phosphate to ternary lithium ion battery technology. Although BYD launched the blade battery in 2020, the magic change to lithium ion iron phosphate battery gives it a chance to remake against the wind, but from the current market point of view, three lithium ion battery is more mainstream.

The maximum energy density of the current liquid electrolyte lithium-ion battery is 350Wh/kg. With the addition of battery management system and other components, the energy density limit is basically 300Wh/kg for the whole system. This still falls short of the goal of 350Wh/kg energy density of power lithium-ion batteries in 2025 mentioned in the Medium and Long Term Development Plan of the Automobile Industry.

In addition to the limit of energy density, ternary lithium ion batteries also have problems such as environmental adaptability, range, safety and so on. Range anxiety has always been considered as a "jam" problem for new energy vehicles, especially in the winter low temperature environment, the problem of mileage shrinkage of electric vehicles is more prominent. The safety of lithium-ion batteries is also controversial, and in 2020 there will be more spontaneous combustion in all electric vehicles.

Cui Dongshu, secretary-general of the National Passenger Car Market Information Joint Conference, also said that "(new energy vehicles) energy should be diversified and the diversified development of new energy vehicle technology route". In addition to power lithium ion batteries, car companies are also laying out the research and development of hydrogen fuel powered lithium batteries, in order to gain first-mover advantage.

Some people in the industry said that, in relation to pure electric vehicles, hydrogen fuel-powered lithium battery vehicles are more in line with the needs and habits of consumers, and the controllability and plasticity of hydrogen are stronger. There is no problem of short range and long filling time for hydrogen fuel-powered lithium battery vehicles. However, Professor Zhang Tong, director of the Institute of Fuel-powered Lithium Battery Vehicle Technology at Tongji University, believes that due to the high technical threshold of passenger vehicles, it is more difficult to commercialize hydrogen-powered lithium battery vehicles in the passenger car field, and it will take at least five years to achieve a small batch of vehicles on the market.

High nickel, all solid state lithium ion battery, etc., who is the future of power lithium ion battery?

In 2020, the domestic new energy vehicle market will begin to show a high rising trend, which will also promote the high rising trend of the power lithium-ion battery industry chain and improve the industry prosperity. Ouyang Minggao said that China's current power lithium-ion battery technology innovation mode from the policy led to the market led transformation, battery system structure innovation, supplemented by small improvements in battery monomer materials has become the characteristics of domestic power lithium-ion battery innovation in recent years.

Released in October 2020 "energy conservation and new energy automotive technology roadmap 2.0", the realization of fully electric car industry transformation, and in the field of power lithium ion battery will cover energy type, power balance and power three categories, compare the energy density, battery life, cost parameters, such as setting the threshold and improve direction.

Entering 2021, new energy vehicle enterprises have pulled open the layout of power lithium-ion batteries. On January 9, NIO announced 150kWh solid-state battery, the range of the first model carrying the battery can reach 1000km. On January 13, SAIC Zhiji Automobile announced the cooperation with Ningde Times to launch "silicon to supplement lithium" battery, the maximum range will be more than 1000km; Zeng Yuqun, chairman of Ningde Times, said on January 16 that the company is developing a BEV battery pack that can achieve a range of more than 1,000 km, a quick charge in 10 minutes, and a service life of 2 million km over 16 years.

Long range is the common pursuit of new energy vehicle enterprises and consumers, which kind of power lithium ion battery is the best choice to meet this demand?

Ningbo allow 100 new energy science and technology limited company president assistant holds general manager of positive electrode division She Shengxian and other people think, below ensuring safe condition, high nickel battery is the future as before. The advantage of the high nickel system lies in the high energy density and specific energy, which directly improves the range of the vehicle. However, the current high nickel battery cost, safety and design aspects need to be improved.

Chen Liquan and other industry insiders believe that the new generation battery approach is to develop solid-state batteries or gradually transition to all-solid-state lithium-ion batteries. "Solid state batteries use solid electrolyte instead of diaphragm and electrolyte, can increase the energy density to more than 300Wh/kg, the vehicle's range is also increased." Chen Liquan said.

Huang Xuejie believes that solid-state batteries have come to a good time in terms of development, and all-solid-state batteries are the ideal model.

It is believed in the industry that the gradual replacement of liquid battery by solid-state battery will be the general trend. According to the technological evolution path of "liquid-semi-solid-quasi-solid-all solid", the content of liquid electrolyte will gradually decrease, and the all-solid-state battery will be the final form. In addition, Chen Liquan believes that sodium ion batteries should be developed at the moment, and lithium-sulfur or lithium-air batteries should be the direction of the next generation in the long run.

In addition to power lithium-ion batteries, technical innovation of the whole vehicle is the direction of the improvement of new energy vehicles. Ouyang Minggao believes that there is an urgent need for environmental adaptation technology of pure electric vehicles, the efficiency of electric thermal management system, the comprehensive utilization of power system energy for winter working conditions, and the gun insulation and pulse heating of battery under charging scenario should be improved and innovated.

Beijing News shell financial reporter Wang Linlin editor Zhao Ze school to Jia Ning