Date: 2024-05-08 hits: 444
Recently, CATL officially released the Shenxing Plus battery at the Beijing Auto Show.
Based on lithium iron phosphate cathode material, the battery not only has a range of 1000km, but also has 4C fast charging capacity, and the battery life of 10 minutes is increased by 600km.
What is more incredible is that the system energy density of the Shenxin plus battery has reached 205Wh/kg, which is 30% higher than the current mainstream lithium iron phosphate battery system of 150-160Wh /kg, and is higher than the energy density of most terpolymer battery systems known for high specific energy (190Wh/kg).
At the press conference, Wu Kai, chief scientist of CATL, mentioned that innovation should be forward-looking, have speed, and be able to land.
So, how is this energy density 205Wh/kg thousand Li endurance lithium iron phosphate battery achieved? What innovative technologies are used?
In the product sequence of the CATL, Kirin batteries have become the representative of ternary materials (although Kirin was concurrently lithium iron when it was first released),
The Shenzhou battery has evolved into a representative of the lithium iron phosphate material, but the Shenzhou battery also has many versions, such as the earliest release of the Shenzhou supercharge battery (4C fast charge) is divided into long-life version and low-temperature version, of which the "long-life version" can support 8 years or 800,000 kilometers of ultra-long cell warranty.
The "low-temperature version" can still be charged to 80% in 30 minutes at -10°C.
In addition, the Xiaomi SU7 Pro version is equipped with the Shenxin all-purpose battery, the system energy density is close to 160Wh/kg, the total energy is also as high as 94.3kWh (support pure battery life of 830km), but limited by the 400V voltage platform and more than 220Ah cell capacity, its average charging ratio is only about 1.68C.
And this release of the Shenxing Plus battery, on the basis of the Shenxing all-powerful battery, one breath will increase the battery life to 1000km, while the average charging rate is also maintained in the Shenxing supercharger 3.6C(refer to the Shenxing fast charge must be Kirin battery), can be described as supercharging + super, is the performance king of high-end lithium iron phosphate.
In order to achieve a thousand miles of endurance, simply increasing the battery energy is not enough, because if the system energy density is too low, most of the increased battery capacity is used to transport the battery itself!
According to the calculation of the blogger, the Tesla Model S 75kWh in accordance with the system energy density of 160Wh/kg, even if the energy is doubled to 150kWh, the battery life is 700km, far less than twice the 469km, it can be seen that the doubling of battery energy can not bring about a doubling of battery life.
So what is the minimum energy density of the system to achieve a thousand miles of endurance?
From the previous mass production of thousands of miles of endurance models, whether it is the Qilima version of GAC AION LX Plus, or the Kirin battery version of KR 001, its system energy density is close to 205Wh/kg(referring to the battery that can last for thousands of miles and can be super fast charged finally realized), so it seems that 205Wh/kg is a value that cannot be turned around.
However, in May 2023, the Qicchen L600 lithium manganese iron phosphate battery released by Guoxuan Gaoko has a single mass energy density of 240Wh/kg, and the system energy density has reached 190Wh/kg, which is officially claimed to achieve a battery life of 1000km(refer to LMFP about to punch LFP and kick NCM).
In addition, at the 2023 financial report investor communication meeting, Wang Chuanfu mentioned that BYD will release the second-generation blade battery as early as August 2024, the energy density will reach 190Wh/kg, and the battery life of pure electric models will break through 1000km.
Combined with these two pieces of information, and the current CLTC test conditions are conducive to the realization of long endurance, the system energy density of 190Wh/kg should be able to achieve a thousand miles of endurance.
For lithium iron phosphate batteries, their mass group efficiency is expected to exceed 85% or even reach an ultra-high level of 90%.
According to the report "New energy enough for power battery technology" in the People's Daily at the beginning of the year, Changan Automobile adopts CTC technology, the group efficiency can reach 86%, and will be mass-produced in 2024 (may be supplied by Changan Times).
If the maximum group efficiency is 90%, the monomer energy density of lithium iron phosphate must exceed 211Wh/kg to achieve 190Wh/kg system.
Such a lithium iron cell was realized as early as 2022, with a cell size of 354*102*11.8mm (soft pack),0.33C capacity of 55Ah, voltage platform 3.2V, weight 830g.
Energy density 212Wh/kg.WNEVC World New Energy Vehicle Conference innovative technology (reference), the use of pre-lithium technology, positive material gram capacity play 150mAh/g, through particle mixing to improve the compaction density, balance performance (but the compaction density is 2.4g/cc).
The negative electrode also uses a silicon-doped design to further increase the energy density.
It can be seen that the use of lithium iron to achieve a thousand miles of endurance is still hopeful.
