In recent years, the power lithium battery using ternary material as the positive electrode material has gradually replaced nickel-hydrogen battery, lithium cobalt oxide battery and lithium iron phosphate battery with its high capacity, good cycle stability (battery life) and moderate cost. The most mainstream battery on the market. Today, Yucheng Solar came to talk to you about what three yuan is the ternary lithium battery.
The ternary of the ternary lithium battery refers to three elements of nickel (Ni) cobalt (Co) manganese (Mn).
Among these three elements, nickel and cobalt are active metals, and manganese does not participate in the electrochemical reaction. In general, the higher the content of the active metal component, the larger the battery capacity, but when the content of Ni is too high, Ni2+ occupies the position of Li+, which exacerbates the cation mixing, resulting in a decrease in capacity.
Co is also an active metal, but it acts to inhibit cation mixing, thereby stabilizing the layered structure of the material.
Mn as an inactive metal mainly serves to stabilize the reaction and improve safety.
Nickel is chemically active but more stable than iron. It is difficult to oxidize in air at room temperature and is not easy to react with concentrated nitric acid.
Cobalt is a moderately active metal. Its chemical properties are similar to those of iron and nickel. Oxidation occurs at high temperatures.
Manganese is a relatively active metal. It combines with oxygen when heated and is easily soluble in dilute acid to form divalent manganese salts.
The nickel-cobalt-manganese ternary material can generally be expressed as: LiNixCoyMnzO2 where x+y+z=1.
It has been found that the ratio of nickel to cobalt in the ternary cathode material can be adjusted within a certain range, and its performance varies with the ratio of nickel cobalt to manganese.
Through a large number of studies, countries around the world have proposed a number of ternary material systems with different ratios of nickel, cobalt and manganese, including 333, 523, 622, 811 systems.
Simply speaking, the larger the first number, the stronger the performance of the battery, the more difficult the production, and the harsher the conditions of use.
The larger the last number, the worse the battery performance and the lower the production cost.
At present, 333 and 523 lithium batteries are the mainstream models of automotive power batteries, and 622 and 811 lithium batteries are also important research directions in China.
At present, the quality of ternary battery products in domestic power battery factories is uneven. The stability of ternary materials is inherently weaker than that of lithium iron phosphate. Coupled with complex process requirements, the production capacity is limited and there is still a long time. The road is going. However, the future of ternary lithium batteries must be the mainstream of the future automotive power battery, as the reason for the opening has been explained!
Some of the images are from the web, thanks to the original author.