CATL shenxing battery vs blade battery base on xiaomi SU7

Xiaomi SU7 is officially released and is divided into three versions. Among them, the rear-wheel drive standard version is equipped with a 73.6kWh blade battery and has a CLTC range of 700 km; the rear-drive Pro version is equipped with a 94.3kWh Shenxing battery and has a CLTC range of 830 km; the four-wheel drive Max version is equipped with a 101kWh Kirin battery and has a CLTC range of 800 km. SU7 is equipped with both blade battery and Shenxing battery. Xiaomi SU7 gives us the opportunity to compare these two most advanced lithium iron phosphate batteries. So comparing the blade battery and the Shenxing battery, which one has better performance?

1.Shenxing battery released

Mathias Huettenrauch, President of CATL Europe, released the CATL Shenxing battery at the 2023 German International Automobile and Smart Mobility Expo (IAA MOBILITY 2023). Through continuous innovation in materials, material systems, and system structures, Shenxing supercharged batteries have broken through the performance boundaries of lithium iron phosphate material systems and pioneered the ultra-fast charging speed of “charging in 10 minutes, Shenxing can travel 800 miles”, redefining the definition of The introduction of lithium iron phosphate batteries can greatly alleviate European consumers’ energy replenishment anxiety.

At the same time, through structural innovation, intelligent algorithms and other methods, the Shenxing supercharged battery can easily reach a range of more than 700 kilometers. Even in a low temperature environment of -10℃, it can be charged to 80% in 30 minutes. By using improved electrolyte and equipped with high safety The coated separator provides “double insurance” for battery safety. It controls the global temperature field through intelligent algorithms to achieve ultimate safety standards and comprehensively improve the overall performance of lithium iron phosphate batteries.

2.Comparison between blade and Shenxing battery

The standard version of SU7 uses a 73.6kWh blade battery with a cruising range of 700km. It can recharge 350km in 15 minutes, which means it replenishes 50% of the electric energy. From this point of view, the average charging rate is 60/15*50%=2C.

In comparison, the SU7 Pro’s Shenxing battery is 94.3kWh, and the comprehensive range has been increased to 830km. It also recharges 350km in 15 minutes, which is 42% of the electric energy. Calculated in this way, the average charging rate is only about 1.68C.

You must know that the maximum charging rate announced by Shenxing Supercharged Battery is as high as 4C when it is released, and it can achieve a range of 400km after charging for 10 minutes, and the average charging rate is above 3.2C. The charging capacity of Xiaomi SU7’s battery is only about half that of Shenxing Supercharger, and even inferior to BYD’s 2C Blade Battery. It is indeed somewhat dwarfed by comparison.

It should be noted that according to the nameplate of the SU7 standard version, its battery capacity is 186.7Ah and its voltage is 394V. According to the maximum voltage limit of lithium iron phosphate battery of 3.65V, its maximum voltage is about 450V, which is exactly on the 486V silicon carbide platform. Within.

Considering that the energy of the Pro version has been increased to 94.3kWh, according to the diagram at the press conference, there are at least 132 strings and a total voltage of 482V, which is very close to the upper limit of 486V. The battery capacity is close to 223Ah, which is about 20% higher than the blade battery.

Perhaps the high capacity is also to blame for the slowdown in fast charging speeds. After all, when the battery core becomes thicker, it becomes difficult to transfer heat, and the same 700A current only has a maximum magnification of more than 3C.

In addition, according to the declaration information of Xiaomi SU7, the curb weight of its Pro version has increased by about 110kg. Assuming that only the battery has increased in weight, and the energy density of the BYD blade battery system is 150Wh/kg and the battery pack is 490kg, then the system energy density of the Shenxing battery is 157Wh/kg, which is slightly higher than the blade battery. It can be seen that at 400V, the battery capacity increases and the proportion of the casing decreases, which is indeed beneficial to increasing the energy density of the system.
However, at the recent BYD 2023 financial report investor communication meeting, Wang Chuanfu revealed that the second-generation blade battery will be released as soon as August this year. Its cell energy density can reach more than 190Wh/kg, and the system energy density will most likely reach 160Wh/kg. , it is possible to overtake Shenxing Battery by then.

Moreover, the capacity of the SU7 blade battery is 186.7Ah, which is not the 135 and 150Ah used by BYD. The length of the battery cell should be halved to about 500~600mm. Maybe the battery cell chemical system has been optimized to not only meet the fast charging performance, but also increase the energy density.

3.Development plan of Shenxing Battery

On the same day that Xiaomi SU7 was released, CATL’s official public account also officially announced the Shenxing battery all-round series, with the slogan “No fear of battery life, freedom to travel” and emphasized the volume group efficiency of up to 77.8% and more than 10 % energy density increase. Considering that the previous system energy density of the blade battery was 150Wh/kg, an increase of more than 10% is relatively close to the 157Wh/kg analyzed above.

The new ZEEKR 001 released at the end of February this year is equipped with Shenxing super-chargeable battery with an energy of 95kWh. As a product under the 800V platform, although the maximum charging rate reaches 5C and can be charged to 80% in 11.5 minutes, the system energy density is only about 131Wh/kg.

It can be seen that for the Shenxing battery, there are not only super-charged versions, but also this all-round version. The former has outstanding charging capabilities, but the system is relatively heavy, while the latter is extremely efficient in terms of volume and can also meet the energy replenishment of about 1.7C. speed.

ZEEKR sale well in China reach 16089 cars at Apirl 2024.

4.Summary from vehiclethermal for Shenxing and blade battery

This may represent the development direction of lithium iron phosphate batteries, which must not only ensure high volume group efficiency and system energy density, but also pursue relatively fast energy replenishment speed, so that consumers can truly buy long-lasting, low-cost and Safe product that charges quickly.Battery technology has developed rapidly in the past two years。