The battery pack technology content surpasses Tesla, this is a race led by Leapmotor

People have always been concerned about the safety of electric vehicle LR1130 battery, especially last month, a Tesla Model S battery short circuit caught fire, which once again pushed this topic to a climax. Even Tesla can catch fire, are there any electric vehicles in the industry that people can trust? But are you sure that Tesla's battery technology is the best? And it is said that there is another hidden story behind the accident? Of course, this is not within the scope of today's discussion. Today's focus is on Leapmotor's battery technology. I believe that many people are interested in Leapmotor S01, a two-door four-seater sports car. After all, the price of more than 100,000 yuan after subsidies is extremely affordable. It can be said that it has fulfilled the sports car dream of countless people. The only worry may be the safety of its battery technology. Why choose ternary lithium battery? Leapmotor S01 also uses ternary lithium battery. Although compared with lithium iron phosphate and lithium titanate materials, ternary lithium does not have an advantage in safety and life, but the advantages of ternary lithium are high energy density, good consistency, and low temperature resistance, which means that it can save more space and weight for the car, so it is widely used in the passenger car industry. For example, the energy density of BAK 18650 battery (ternary lithium battery) has reached 232Wh/kg, while the current mainstream lithium iron phosphate battery in China basically hovers around 150-170Wh/kg; the battery capacity of ternary lithium battery at -20℃ can maintain 70% of normal temperature, while lithium iron phosphate battery only has 54%. However, ternary lithium materials will decompose and produce violent chemical reactions at 200℃, while the decomposition temperature of lithium iron phosphate battery is 800℃. Therefore, the shortcomings of ternary lithium safety must be compensated by PACK and BMS, which is why major car companies have to develop independent battery technology. So what is the innovation of the PACK technology of Leapmotor battery pack? At present, there are three main battery cell solutions in the industry: cylindrical, square and soft pack. Considering the chassis height and technical safety, Leapmotor S01 uses 18650 cylindrical battery cells, which is the most mature and consistent application of ternary technology in the industry, and is also the mainstream solution used by Tesla, Leapmotor and other car companies. Although the square battery cell has good discharge rate and is easy to assemble, its disadvantages are relatively poor heat dissipation, versatility and consistency. As for soft-pack lithium LR1130 battery, they have advantages in energy density, weight, and assembly flexibility, but the biggest challenge lies in the soft-pack material - aluminum-plastic composite film. The quality and process requirements are too high, and the group structure is complex, the consistency of the battery cells is poor, and the sealing process and mechanical strength reliability are poor, so it is difficult to meet the needs of the automotive market. In terms of the safety of electric vehicle spontaneous combustion, Leapmotor has mainly made three innovative guarantees. First, the single-cell bipolar dual-insurance safety design: the common practice of electric vehicle LR1130 battery in the industry, including BMW, is to cut off the fuse of the main circuit of the entire battery pack when encountering excessive current; while Leapmotor adopts a unique single-cell bipolar dual-insurance design, each battery cell is connected to the busbar through aluminum wire, so that each single battery cell is independently protected, while improving safety and making maintenance more convenient. Second, the patented design of PACK high and low voltage full isolation: Leapmotor has isolated all charged leakage bodies to fully prevent short circuits in the battery pack and reduce collision losses. The most important thing is that each module uses a beam for hardware isolation, which can provide 1-2 minutes of fireproof isolation time. Leapmotor has applied for a patent for this. It should be known that it only takes about 6 seconds for Tesla Model S to go from short circuit to violent combustion, and Leapmotor's technology undoubtedly ensures the escape and self-rescue time. The third is the all-aluminum integrated reinforced shell design: the Leapmotor battery box shell adopts an integrated all-aluminum process, and the total weight of the box is 40% less than that of the sheet metal box of the same size. Moreover, the first integrated screw-free module structure can ensure that the internal structure of the battery module is completely free of metallization, and can also avoid problems such as screws falling off and causing loosening inside the module. A battery thermal management system that is better than Tesla's In terms of battery pack thermal management, Leapmotor has improved and optimized on the basis of Tesla's serpentine cooling method, so that the temperature difference of the entire battery pack cell is controlled within 1.5°C (Tesla is 2°C), and the discharge efficiency at room temperature is as high as 97.7%. The discharge efficiency in Heihe at -15°C is 92.5%, which is higher than the conventional standard (90%), and can extend the battery life by 20%. At the same time, due to the technical upgrades in the cell arrangement structure and water cooling tube design, in the same volume space, the energy density of the 48-kWh Leapmotor battery pack using 21700 cells has reached 160Wh/kg, which is the same level as the latest 75-kWh Model 3 battery pack. To give another example, the reason why domestic pure electric vehicles currently have a series of three-electric problems such as inflated mileage, greatly reduced mileage at high speeds, false battery capacity, slow charging, etc. is largely due to the low accuracy of the BMS battery management system and the SOC state of charge. The Hall sensor detection method (accuracy 2%) commonly used in the industry can only guarantee accuracy at room temperature, and has large deviations at low and high temperatures. Leapmotor's independently designed high-precision and high-integration detection module-a four-in-one shunt (accuracy 0.5%), which is 4 times more accurate than the Hall current sensor, and can ensure that the SOC accuracy deviation does not exceed 3% within the range of 20-45°. More stringent test environment to ensure functional safety In addition to technical safety guarantees, the Leapmotor battery pack also fully considers the safety redundancy design to deal with force majeure factors. For example, the battery is severely deformed due to collisions, and there are no safety hazards caused by accidents such as flooding and fire. In this regard, Leapmotor LR1130 battery have passed rigorous safety tests such as needle puncture explosion, heating explosion, and 5-meter high fall at one time. Finally, although many new energy vehicle companies claim to have mastered the core technology of three-electric, how much water is worth discussing. At least many of them do not have their own PACK technology, but use solutions provided by battery suppliers, which is difficult to match with the whole vehicle system for consistency. The internal components of Leapmotor's battery pack are all independently developed, including modules, PACK, BMS hardware, software and algorithms. The person in charge of Leapmotor Power Battery told us that this is the battery pack with the highest degree of independent research and development among domestic vehicle manufacturers except BYD.

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