The 46800 lithium battery was first adopted by Tesla and became famous. Its naming is based on the battery’s diameter of 46mm and height of 80mm, with the last “0” representing a cylindrical battery. We jokingly call it "No. 1 Battery", and abroad it is known as "Cracker Barrel".
Since Musk “crazily promoted” 46800 on Tesla’s Battery Day on September 22 last year, we learned that this self-developed battery can increase the energy of a single unit by 5 times and charge and discharge. The power is increased by 6 times and the cruising range is increased by 16%. Compared with existing lithium batteries, its advantages include lower cost, greater energy density, and higher charge and discharge power limit.
However, investors did not buy it when it was released. After Tesla's Battery Day, the company's stock price turned from rising to falling. It was not until a long time ago that it hit a new high of $800 billion in market value. (Of course, the rise in stock prices is a manifestation of the accelerated virtualization of assets, which is another topic.)
With the advent of blade batteries, cobalt-free batteries, and disruptive solid-state batteries, not only have batteries Manufacturers have also allowed car companies to usher in an active or passive revolution. So, why does JAC New Energy have a soft spot for 46800, and where does it come from such confidence?
Correctness of the path
In fact, the essence of this question is, why does Tesla want to develop 46800 batteries? Musk, who acts based on first principles, will not develop a product that does not seem to be disruptive for no reason and will even be criticized by talk shows. Moreover, many people in the industry underestimate the role of 46800 batteries. Therefore, we need to interpret the true strength of the 46800 battery.
Previously, Tesla has hinted that there will be multiple "blockbuster" bombs in the battery field, such as batteries with a service life of up to one million miles and dry electrode technology that can significantly increase the energy density of battery cells. etc. The 46800 battery is a special one.
This is also the point where the 46800 battery has been criticized. It does not have the "million-mile" function. According to Tesla’s previous introduction, through the innovation of electrochemical systems, the batteries it developed can enable vehicles to travel millions of miles, and the service life of the batteries can be as long as 10 years or more. However, Musk said nothing about this at Battery Day.
However, one thing that needs to be pointed out is that the energy density of the 46800 battery has not actually improved much. According to calculations, it is roughly around 283Wh/kg (battery weight energy density = battery capacity discharge platform voltage/weight, The basic unit is Wh/kg). Taking into account other technical improvements, the total capacity of the 46800 battery cells should be able to reach 30Ah. The energy density should be able to reach 300Wh/kg.
There is a "siege lion" analysis in the industry, "It is not clear to choose this size. It is generally believed that the diameter of a cylindrical battery exceeds 30mm, and the temperature difference between the inside and outside of the cell will be large, affecting the safety performance of the battery. 46800 cells are currently It is difficult to pass the test when making ternary products, and it is much safer to make 32800, 32145, etc. from domestic Guoxuan. This makes us consider that Tesla’s focus is on reducing the cost of the battery system. Cost, rather than improving battery performance. ”
So, why did Tesla change from 21700 to 46800 batteries? Why did JAC follow up? This is worthy of deep thought by the industry.
In fact, through structural improvements, material changes and process innovations, this 4680 battery cell will exert huge energy. This is also the reason why JAC is determined to follow up. Of course, except for JAC, no domestic car company seems to have publicly taken this route. BYD and CATL remained silent.
According to foreign media CleanTechnica, after redesigning the battery, cathode and frame, Tesla’s cost per kilowatt-hour is expected to increase by 56%. In other words, the cost can be reduced by 56%. This will change the "rules of the game" and enable a new generation of low-cost electric vehicles. "It all started with a humble battery." Wow, you look down on batteries so much.
Currently, Tesla’s official video also shows that batteries are being produced in full swing. Tesla's supplier Panasonic plans to invest in a trial production line at the Osaka factory.
Production of the 46800 cells is expected to begin in 2022. However, Tesla is still hiding the core technology dry electrode technology it mastered from its $218 million acquisition of Maxwell in February 2019. Let’s ignore this for now and focus on returning to the 46800 battery.
How strong is 46800?
Why will JAC follow up with 46800 batteries? This means that the 46800 battery has the ability to truly subvert the era of fuel vehicles?
The patent for this 46800 battery was submitted by Tesla in November 2019. Thanks to the increased size, the energy of the battery cell has been increased by 5 times, and the cruising range has been increased by 16%. Another feature of this large "No. 1 battery" is that it is a "poleless" battery and is "flat". This is mainly done to eliminate the heat generated by the tabs of traditional cylindrical batteries and solve the heat dissipation problem of the battery cells.
Specifically, the 46800’s tabless design (or full tab design) uses laser technology to remove the protruding tab structure of the traditional battery. In this way, the conductive coating is directly in contact with the battery. The contact between the end caps can greatly shorten the distance that the current moves and reduce the internal resistance. In addition, the effective contact area between the conductive coating in the tab electrode and the battery end cover reaches 100%, greatly improving the heat dissipation capability.
Moreover, the tabless structure design of Tesla’s 46800 battery directly helps improve manufacturability. A thermal management engineer at a new energy OEM commented: "Compared with the improvement in performance, I personally think that the design of eliminating the tabs is disruptive to the change of the industry. For battery thermal management, the reduction of heat also means that the battery fluid The design of the cooling system may not be necessary. ”
In fact, it is not unnecessary, but because the pole lug is eliminated, it is no longer necessary to follow the principle of positive pole upward, so the battery cells will be connected to the chassis with the positive pole. , the negative pole is on top. The liquid-cooling plate after the battery cells are turned upside down is placed on the top of the battery pack, which is more conducive to constant temperature. This is the information "spoiled" by overseas media in January.
As for the cathode material of the battery, Tesla uses high-nickel materials. By using higher nickel materials, high energy density and long range can be achieved. According to Musk's calculations, 46800 uses a nickel-manganese structure, which can increase the range of electric vehicles by 16% and ultimately achieve a 15% cost reduction.
However, industry expert Zhu Yulong also said that China, Japan and South Korea, which were early in the research and development of lithium batteries, encountered great challenges in exploring this aspect and could not achieve it overnight. Among the three directions announced by Tesla, most of them are from the laboratory to the pilot test stage, and many of the data listed are based on paper. Vertical integration of battery cells requires a lot of work. There is currently no bottom line as to whether the 4680 battery cells manufactured by Tesla are reliable.
However, we still admire Tesla’s courage. Currently, many traditional car companies are facing what Harvard professor Christensen calls the "innovator's dilemma" in the field of new energy. In his view, “The more excellently managed a company is, the more difficult it will be to get out of trouble when the moment of ‘disruptive innovation’ arrives.” Therefore, many companies follow the rules and do not dare to take a step beyond the limits.
Tesla’s 46800 battery is a typical example. As a technological innovation of a “disruptive technology” nature, its technological products are unprecedented and completely emerging things. For traditional car companies, disruptive technologies often target an undetectable area at the beginning. It cannot meet the growth needs of traditional scale and strong manufacturing capabilities, which poses a challenge to the decision-making of traditional car companies.
End the era of gas trucks?
Currently in China, JAC is the first car company to follow up on the 46800 battery. After 15 years of research, JAC turned to 46800 batteries. It can be judged from this that JAC recognizes Tesla's forward-looking route and believes that this direction is correct. The reason why JAC invests so much in the research and development and application of 46800 batteries is that it has "clearly seen the future trend."
The technical person in charge of JAC said, “After the launch of 46800, it will be a boost for all batteries in our industry.
After this specification is released, its volume, energy density, and its technology, as long as this combination is reorganized, this battery cell can be used to make a small car (A0 level and A00 level) with a range of 600km. I tell you today that a standard A-class car can travel 800 to 1,000 kilometers. Do you think the era of gas vehicles is coming to an end? ”
Of course, this is based on a cognitive basis. The biggest difference between pure electric vehicles and traditional fuel vehicles is that the electrified architecture will bring intelligence that fuel vehicles cannot achieve, thereby bringing about Give users a more pleasant experience. The changes in 46800 batteries will push car companies to get closer to this trend.
From the perspective of product mass production, Sihao New Energy’s solution for A00 products. Yes, “Based on 46800 materials, lithium iron phosphate can achieve a range of 300 kilometers; ternary lithium batteries can achieve a range of 500~600 kilometers. Our preliminary plan can become a reality in two years. "This is a very good data.
We know that in addition to battery cells, there is also strong technology in BMS and PACK to form a complete system. In this regard, Sihao New Energy in 2020 The release of "cellular battery" battery technology is undoubtedly quite consistent with the 46800 battery.
The technical person in charge said that compared with ordinary power lithium batteries, "cellular batteries fully draw on the honeycomb structure. The bionic design is unitized with epitaxial coating of UE technology, and all cells in the lithium battery pack are 360-degree coated with lightweight self-leveling thermal conductive glue. "Thermal conductive glue can ensure a temperature difference of 3% inside the battery pack, thereby achieving electrical and thermal isolation between lithium battery cells. Moreover, if one cell fails, it will not affect the surroundings, so it will not cause a chain reaction. This If the technology is combined with the energy improvement of the 46800 battery, it will undoubtedly be JAC's confidence.
On February 1, 2021, JAC Motors and CBAK Energy Technology signed a three-year joint product development strategic agreement. According to the agreement, CBAK Energy Technology will provide customized solutions for power batteries and battery packs based on JAC Motors' technical requirements. The two parties will also jointly develop 46800 cylindrical lithium batteries and battery packs.
CBAK is the modification. The famous BAK Battery was established in August 2001 and is now called Zhongbi Energy Technology Co., Ltd. It was listed on Nasdaq in 2006 and became the first Chinese lithium battery company to be listed in the United States.
After signing the contract, JAC Motors and CBAK will also set up a joint R&D team to design, test and enhance the adaptability of their new products in the field of electric vehicles. JAC said that in the future, it will give priority to using the batteries and batteries jointly developed by both parties in the electric vehicles it produces. Battery pack system. In other words, if the 46800 battery is mass-produced in 2022, it will be used in Sihao New Energy vehicles.
It needs to be reminded that, as the famous financial writer Wu Xiaobo said, “From technology to monetization, it is a thrilling leap, and how much cash on the account and team enthusiasm will be burned in the process. "After all, there is great uncertainty about whether the company's technical route can achieve good market results. Compared with the current soft packs and square cases, the 46800 battery is still in a marginal position. Just because Tesla We expect to see more 46800 battery applications in the next five to ten years. Of course, there are many factors that will lead to the end of the oil truck era. It is understood that before 2030, the situation of fuel and pure electric power will continue to exist and even be dominated by fuel. The success or failure of new energy transformation is a sudden change in the automobile industry, which means in a larger sense. Knock it down and start over." Whether 46800 can become the mainstream of power batteries in the next five to ten years is still unknown, and you need to be mentally prepared.
Text/Wang Xiaoxi
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