With the widespread popularity of electric vehicles, a lot of friends have been asking questions about power batteries. Shock, as an adventurer, can ignore anything else, but he attaches most importance to the reliability of his adventure equipment. I’m here today with a good friend of mine to talk to you about power batteries.
Hi, I am the star member of the power battery family, Manganese, or NCM. The history of our power battery family dates back to 1837. At that time, Robert Anderson of Scotland fitted the carriage with batteries and electric motors, and successfully transformed it into the world’s first electric vehicle. So why did electric cars come so late? Mainly because of battery life, charging time, safety and other key issues. The members of our family were born to solve these problems.
More well-known are lithium iron phosphate batteries, lithium titanate batteries, and I and my brother nickel cobalt aluminum ternary lithium battery (NCA). We are made of different elements, so we have different abilities and characteristics. Lithium-iron phosphate batteries, for example, are the best and most stable, but they don’t store enough energy (energy density) for the same volume, which affects the vehicle’s endurance. Then there are the lithium titanate batteries, which discharge quickly and provide a powerful output, powering buses and tanks. However, its energy density is relatively low, and the raw materials and production costs are too high, so the general electric car is not willing to use it. Finally, my brother and I, with our good temper, high energy density, and ability to balance range and stability, are now the preferred battery for consumer electric vehicles.
Scientifically speaking, ternary lithium battery is a kind of lithium battery with nickel-cobalt element as cathode material and manganese salt or aluminum salt to stabilize the chemical structure. My advantage has already said before, here mainly say my temper. My temper is ok, but I can get angry and out of control if my brain is short-circuited or I get hit, punctured or roasted. So in order not to annoy me, scientists have worked hard on the choice of metal salts and packaging methods.
Choice for stability: Aluminum or Manganese?
My brother and I still have different personalities and characteristics. The production of nickel, cobalt and aluminum is not only high in technological requirements and cost, but aluminum can improve the chemical stability of the battery cycle. With the ternary system, the nickel content can be improved to a certain extent, so as to achieve higher battery energy density. However, the crystal structure of Nickel-cobalt-Aluminum is more unstable than that of nickel-cobalt-manganese, and it is easy to collapse and lead to thermal runaway at a higher temperature, thus causing risks. In contrast, although the manganese element in my body is difficult to stabilize more nickel, the current nickel-cobalt-manganese system has a lower energy density and thus its endurance performance is not as good as that of nickel-cobalt-aluminum, but the manganese ternary system has better thermal stability and less nickel content, so it is safer as a power battery.
Choice of packing method: round or square, soft or hard?
The nickel, cobalt and manganese in my body breaks down when it reaches a certain temperature, releasing oxygen, which speeds up the reaction of the electrolyte at high temperatures, creating a risk. So I need a more reliable way of packing. At present, the most mainstream way has three kinds: cylindrical, square shell and soft bag.
Cylindrical type: the cell is packed in a tightly wound way, with more compact internal arrangement and more concentrated energy. However, because the cylindrical battery is small in size, if you want to provide more energy, you need a large number of individual batteries to form a battery pack, so it is difficult to guarantee the consistency of the battery. Improper battery consistency management can lead to a variety of adverse results, one of which is increased internal resistance resulting in a dangerous loss of internal temperature of the battery.
Square shell type: can roll the internal material more tightly, coupled with the aluminum shell is not easy to expand, so it is relatively safe. This kind of packing can be equipped with explosion-proof plug inside, if there is heat out of control, the expansion air will be released from the fixed direction of the explosion-proof plug, and it is not easy to affect other electric cells.
Soft package type: in the structure of aluminum plastic film packaging, because there is no space limitation of aluminum shell, so in the same volume of the condition can be loaded into more energy, the most direct and thorough reaction. But also because there is no limit to the aluminum case, the battery pack is prone to air or deformation, which could be a safety hazard.
I made the ES8 stronger and more stable
Based on the advantages and disadvantages of metal salt selection and packaging method selection, nickel-cobalt-manganese ternary lithium battery packaged in square shell can not provide more energy, but has higher thermal stability and controllability. At the same time, in line with the German Federation of automotive Industry VDA standard square cell module, has far more than the national standard of battery decay rate, and higher energy density. Because of this, I became a good brother who could fight with ES8.
We’ll talk about batteries again. Mainly want to discuss with you from a professional point of view, the birth of a good battery is not easy. If you have any battery questions or tips, let us know in the comments section.