What are the advantages of ternary lithium-ion batteries? Why are ternary lithium used in the market?

The capacity of the battery determines the cruising range and charging time, which are the most important parts of the user experience. Of course, from the perspective of the automotive industry product, there are several more dimensions that determine the power lithium battery, such as safety, energy density, nominal voltage of the unit, service life, application cost, low temperature attenuation ability, etc. There are strict international and domestic standards, and models that can be marketed must first meet the standards.

I believe that many friends who are concerned about electric vehicles will not be unfamiliar with the ternary lithium-ion battery. The famous Tesla uses this battery. The domestic battery giant BYD has been using lithium iron phosphate batteries for a long time in the past, and announced in the second half of this year that it will also focus on the development of ternary lithium-ion batteries. So, what exactly is a ternary lithium-ion battery? Why has it suddenly become the darling of power lithium batteries?

The ternary polymer lithium ion battery refers to a lithium ion battery that uses lithium nickel cobalt manganate (Li (NiCoMn) O2) ternary cathode material as the cathode material, and the ternary composite The cathode material precursor products are made of nickel salt, cobalt salt, and manganese salt. The ratio of nickel, cobalt, and manganese can be adjusted according to actual needs.

Safety is the top priority

The ternary lithium-ion battery is characterized by high energy density and higher voltage , So the battery capacity of the battery pack of the same weight is larger, the distance of the car is also greater, and the speed can be faster. But its weakness lies in its poor stability. If there is an internal short circuit or the positive electrode material meets water, an open flame will appear. Therefore, generally 18650 batteries will have a layer of steel protection. Since Tesla’s battery pack is composed of about 7000 18650 batteries, although Tesla has carried out all-round protection for the battery pack, it is in the extreme In a collision accident, there are still potential fire hazards.

The reason for this is that the two materials decompose when they reach a certain temperature. The ternary lithium material will decompose at a lower temperature of about 200 degrees, and the lithium iron phosphate The material is around 800 degrees. And the chemical reaction of the ternary lithium material is more intense, it will release oxygen molecules, and the electrolyte will burn rapidly under high temperature use, and a chain reaction will occur. To put it simply, ternary lithium materials are more likely to catch fire than lithium iron phosphate materials. But it should be noted that we are talking about materials, not batteries that have become finished products.