Ternary lithium-ion batteries have high energy density, long cycle life, and are not afraid of low temperature; insufficient stability at high temperatures. Energy density can reach the highest, but high temperature sex is relatively poor, about range requirements of pure electric vehicles, its is the mainstream direction, and suitable for the northern weather, low temperature when the battery is more stable. Tesla announced the Model 3, that is, using Panasonic's 21700-type ternary cylindrical battery.
The disadvantage is that the ternary material deoxidation temperature is 200 ℃, and can not pass the pinprick experiment, indicating that the ternary battery in the case of internal short circuit, battery shell damage, easy to cause combustion, explosion and other safety accidents.
Ternary lithium-ion batteries in the end is which three yuan? Ternary lithium-ion battery "ternary" refers to a polymer containing three metal elements: nickel (Ni), cobalt (Co), manganese (Mn) or aluminum (Al), which is used as the positive electrode in ternary lithium-ion batteries. All three are indispensable and play a huge role in the internal use of the battery.
Nickel: Important use is to enhance the volumetric energy density of the battery, which is an important breakthrough to improve the range, but too much content will lead to nickel ions occupying the position of lithium ions (NiMH mixed row), resulting in a decrease in capacity.
Cobalt: Inhibits the mixing of cations to improve stability and extend the life of the battery, in addition, it also determines the charging and discharging speed and efficiency of the battery (multiplier performance), but too much cobalt will lead to lower actual capacity.
Aluminum or manganese: Cobalt is a very expensive rare metal with high cost, and the use of manganese or aluminum is to reduce the cost of cathode materials while improving the safety and stability of the battery.
In order to improve the capacity of ternary lithium-ion batteries, the proportion of nickel in the cathode has to be increased. So the proportion of nickel is increasing, from the early NCM111, to the last two years of NCM523, NCM611, and then this year have been on the NCM811, the battery energy density is getting bigger and bigger, nickel is also more and more vigorous.
With more nickel, the proportion of cobalt and manganese will be reduced. Will the life and stability of the battery be affected? Theoretically, but now the ternary lithium-ion battery protagonist is undoubtedly the "high nickel" ternary lithium-ion battery. This is partly due to policy reasons, long range, high energy density of the battery electric vehicles, can get more financial subsidies; on the other hand, the car manufacturers to grab the limelight, to engage in range race, as if who's car range is long, who's technology is advanced.
With the subsidy policy "ramp down" and out, ternary lithium-ion battery "high nickel" impulse may be calm. And with the advancement of lithium iron phosphate technology, and ternary lithium mutual competition for the longest is expected. BYD revealed in August, will launch a new generation of lithium iron ion batteries, volume than the energy density will be increased by 50%, life expectancy of up to 8 years and 1.2 million kilometers, the cost can also save 30%. Some analysis says that the energy density of lithium iron phosphate is expected to be comparable to 622 ternary lithium-ion batteries, honestly so, and then good safety, long life, low cost added, lithium iron phosphate ion battery is not likely to return to center stage.
Lithium-ion iron phosphate batteries and ternary lithium-ion batteries, can not simply say which is good, can only say that each is good at winning. Lithium-ion iron phosphate batteries win in long life, good safety, low cost, but the energy density and low temperature performance is slightly inferior; ternary lithium-ion batteries win in energy density, more electricity storage, but safety and life is slightly inferior.
