On July 12, 2020, BYD's flagship sedan, BYD Han, was officially launched. The new car is positioned as a medium and large car, including EV pure electric and DM plug-in hybrid power versions. The price after subsidies The range is 219,800-279,500 yuan.
At the new car launch conference, BYD Chairman solemnly introduced the core highlight of BYD Han - the "blade battery" developed based on lithium iron phosphate battery technology, and confidently declared that " The successful development of blade batteries will remove the word spontaneous combustion from the dictionary of new energy vehicles." So, can the "blade battery" equipped by BYD Han really never spontaneously ignite? Is it really as good as Wang Chuanfu says?
Blade batteries are not absolutely safe
The current mainstream models in the new energy vehicle market tend to use ternary lithium batteries, mainly because ternary lithium batteries with higher energy density can ensure Longer cruising range. But what is unavoidable is that judging from the actual use of electric vehicles, ternary lithium batteries cannot completely avoid safety accidents such as spontaneous combustion.
So, is the "blade battery" developed based on lithium iron phosphate battery technology carried by BYD Han absolutely safe?
In terms of energy density, ternary lithium batteries are higher than lithium iron phosphate batteries. Lithium iron phosphate batteries are restricted by their own materials. When the energy density increases to a certain level, it will encounter a ceiling that is difficult to break through. Although in theory, lithium iron phosphate batteries may be safer than ternary lithium batteries, in fact lithium iron phosphate batteries have also caught fire. Moreover, whether a battery is safe or not is closely related to the production process, quality control process, etc., in addition to the material itself. Therefore, we can only wait for the market and time to test the safety performance of the blade battery carried by BYD Han.
The poor low-temperature performance of blade batteries
The poor low-temperature performance of lithium iron phosphate batteries has also been an unresolved issue for blade batteries. The 76.9 kWh lithium iron phosphate blade battery equipped by BYD Han is officially announced to have a cruising range of 605km. However, this is a digital representation of the endurance under ideal conditions in the laboratory. Due to the low temperature environment in winter, the endurance of the lithium iron phosphate battery will be greatly reduced. , BYD Han's cruising range performance will also be greatly reduced.
The blade battery structure is easily damaged and difficult to repair after a collision
The blade battery eliminates the structural beam of the battery case, and uses each cell case of the blade battery to act as the beam of the battery. The structural strength of the battery system is based on the cell structure, which directly withstands external forces. If you want to protect the blade battery, you can only use the structural combination of the car body and the battery system to prevent the collision from squeezing the battery core and ensure that the battery core is intact after the collision as much as possible. But in fact, if a side impact or other collision occurs, as long as a single battery cell is damaged, the entire series of battery cells will be difficult to repair.
This article comes from the author of Autohome Chejiahao and does not represent the views and positions of Autohome.