On March 1, Li Auto’s pure electric flagship MPV model - Li Li MEGA arrived as scheduled amidst much attention. This futuristic-looking Ideal's first pure electric vehicle has a resounding slogan - "500 kilometers of range after 12 minutes of charging". It has achieved a 5C charging speed that is a leap forward, so for the first time it is equipped with a vehicle jointly developed by Ideal and CATL. What are the unique features of the Kirin 5C battery?
01 From initial cooperation to joint research and development, three years of hard work
Talking about the origin of the cooperation between Li Auto and CATL, Dr. Liu Zhimin, Senior Director of Power Battery at Li Auto, expressed his emotion that they have been partners with CATL for a long time. Since its establishment in 2015, Li Auto has been jointly developing its first-generation product, Lideal ONE, and its second-generation L series with CATL. CATL, which has the world's largest market share for seven consecutive years, is a leader in the industry and an excellent partner. At present, most of the 680,000 vehicles that Li Auto has delivered are batteries supplied by CATL for Li Auto. When talking about these delivered vehicles, Liu Bo eloquently stated the achievements worthy of praise - "Currently, the Li Auto brand maintains a record in the entire industry. None of the vehicles delivered to users caught fire due to the battery itself. This is also a very rare data, which cannot be separated from the joint efforts of both parties and the R&D capabilities of CATL.”
In 2020, Li Auto and CATL launched a more in-depth joint engineering development. Both parties gathered the best scientists and engineers, invested a lot of resources, and jointly embarked on the long journey of supercharged battery research and development. The three-year development cycle is at least twice as long as the normal project cycle. Unsurprisingly, it encountered many technical difficulties. To ensure a cruising range of 700 kilometers, the high density of the battery must be taken into consideration, and the safety of the battery must be ensured. It also needs to provide long life... More than 1,000 people were invested in the entire project cycle, which is 5-8 times more than the investment in ordinary battery development projects. Judging from the results, all difficulties have their value. After three years of joint efforts, 5C battery cells, 5C battery thermal management, and 5C battery safety architecture were finally created.
02 The achievement of Kirin 5C battery: What is the difference of CATL
Gao Huan, CTO of CATL’s Domestic Passenger Car Division, said that the first is the customized service of Kirin batteries, which is provided based on the differentiated needs of the entire vehicle. CATL is divided into different matrices based on the super performance of Kirin batteries. For example, the Kirin batteries currently installed on other models on the market - the world's only large-scale mass-produced Kirin ultra-long-lasting battery equipped with Jikrypton 001, such as strong discharge capacity , the battery of the Extreme Krypton FR that can accelerate from 0 to 100 seconds in two seconds, etc. In the future, Kirin Battery will also develop different performance matrices to meet the needs based on the super attribute positioning of the entire model by the OEM to achieve precise services.
The second is the accumulation of big data and huge investment in research and development. CATL’s power battery usage has ranked first in the world for seven consecutive years, and the number of vehicles it has served has reached 11.67 million. This is an absolute advantage in battery operation big data, which can feed back very detailed battery usage information, such as when the battery is used in certain Based on the specific needs of the situation and what kind of problems occurred, the product is optimized through the closed loop of the entire algorithm, and deficiencies are found and filled. This data is the unique premise and advantage of CATL over the entire industry. In addition, Ningde Times continues to invest in R&D, with annual R&D investment accounting for approximately 5-7% of turnover. In the first three quarters of 2023, R&D investment was nearly 15 billion, which is used for product development iteration and improving the understanding and promotion of power batteries.
03 Exploring the road of taking into account large power and high-rate charging capabilities
The range anxiety of pure electric models has become a common topic. In recent years, intelligent driving of pure electric models has become more and more practical, and the update and iteration of technological configurations have become more and more sophisticated and standardized. However, the efficiency of energy replenishment has not actually been improved. Subversive changes can occur. It seems that driving a pure electric MPV full of family members without replenishment has become a far-off dream. Why is it that before the ideal MEGA equipped with Kirin 5C battery is launched, the pure electric MPV on the market is Can’t electric MPVs take into account longer cruising range and faster energy replenishment efficiency at the same time?
The physical characteristics of the battery have determined that the higher the energy density, the lower the charge and discharge capacity. Taking into account high energy density and high power charging at the same time, this poses a huge challenge to the structure and materials of the battery. The 5C mentioned in the previous article refers toIt is the multiple of the battery charging current divided by the battery capacity. Under the 5C peak rate capability, the battery peak charging current can reach 5 times of the battery capacity. Currently, some high-energy-density batteries on the market have a cruising range of up to 800km, but the peak charging rate cannot even reach 2C. Even if such a speed is achieved, it is difficult to maintain high-power charging for a long time. On the other hand, some batteries with a 4C rate have a battery life of only 200 or 300 kilometers, which also has obvious shortcomings.
The unique feature of the Kirin 5C battery carried by Ideal MEGA is that the 5C recharge speed of 12 minutes of charging and a range of 500 kilometers makes it the fastest recharge battery in the world, and can sustain high-rate fast charging for 10 minutes. Above, the high-rate fast-charging batteries currently claimed in the industry can usually only last for about 5 minutes. At the same time, the Kirin battery equipped with Ideal MEGA can also achieve a long battery life of more than 700 kilometers. Combined with the Ideal thermal management control algorithm and 5C super recharge network, it can achieve faster energy replenishment in a wide temperature range.
04 Charging speed is a requirement and battery safety is fundamental
Battery safety is a top priority for pure electric vehicles, and news about batteries spontaneously igniting and catching fire in collisions is always worrying. How does the Kirin 5C battery, which is superimposed with multiple buffs such as 800V high voltage, more than 100 kilowatt hours of electricity, and 5C overcharge, ensure safety?
Normally, in order to verify the thermal failure control ability of the battery cell, an external trigger is used to cause a battery cell to fail to evaluate the thermal diffusion state of the battery, which is called a thermal diffusion test. The current national standard is that after a heat diffusion alarm is issued, it will take five minutes before an open flame or even explosion occurs, giving users enough time to escape. Some excellent products on the market currently operate at a normal temperature of 25°C. Under water-cooled working conditions, heat diffusion does not occur in the entire battery pack. However, MEGA's Kirin 5C battery raises the room temperature from 25°C to 50°C, simulating more For extreme working conditions, ensure that there is no open flame in the battery so that users can leave the vehicle safely. For emergencies in the event of a collision, the national standard is: no fire or explosion in the event of a lateral collision. When an ideal MEGA achieves a side impact, the battery core will always maintain zero deformation, zero leakage of coolant, and all energy-bearing areas cannot have any contact.
Extremely high safety standards undoubtedly place more stringent requirements on the manufacturing process. Since the Kirin 5C battery is produced in the Lighthouse Factory of CATL, the Lighthouse Factory represents the world’s highest level of digitalization and power battery manufacturing. Currently, the world’s The only three lighthouse factories in the lithium battery industry are all from CATL. High standards of standardized production undoubtedly contribute toMEGA's battery safety provides strong support, and all process data will be stored in the entire system for ten years, and the data can be traced. The production data of these batteries uses a large number of AI algorithms to capture any abnormal values in the manufacturing process of a battery. In addition to the requirements of the original safety standards, redundancy is also made for the safe use boundaries of the battery. In addition, After delivery, the safety of the battery in the vehicle, charging station and cloud will be monitored to provide all-round protection for battery safety.
Write it at the end
In recent years, Ningde Times has used rapidly iterative battery performance and sophisticated customized services to have great advantages in many product competitions, especially in mid-to-high-end intelligent models. With the launch of super-charged batteries, CATL’s complete product matrix will further consolidate its global leading position. The iteration of charging speed is always on the way. Together with the resounding slogan of Ideal MEGA - "charging in 12 minutes and a range of 500 kilometers", the 5C era has arrived.
Editor in charge: Yu Tongtong