Sentence | 7 No. - Song
If you want to say what is the ultimate form of automotive power battery, solid-state batteries must have a seat.
Recently, Denza Zhao Changjiang and Zhiji Liu Tao simply started online PK. Zhao Changjiang said: Now the propaganda of semi-solid-state batteries is playing with words. Liu Tao responded: Not good at word games, the industry's first fast-charging solid-state battery is about to be on the Zhiji L6.
Soon, Haobo also threw out the news of "all 100% solid-state batteries", which had the meaning of mocking the friend "Zuo Jia".
The Zhiji L6 solid-state battery is easy to use
但要「慎用名号」
The solid-state battery is ridiculed as "Schrödinger's dynamic battery", which means that it is always pulled out to blow the concept, and the landing is far away, and the concept is not blown, sometimes whether it is solid or semi-solid, there is no certainty.
To distinguish between a liquid, semi-solid, or all-solid state, the focus is on the state of the electrolyte, which provides a medium for electron transfer. Like "porridge" is a liquid battery, like "porridge" is a semi-solid, like "cooked rice" is a solid state.
Comparison of the internal structure of a liquid battery and a solid-state battery. Liquid lithium batteries mainly use ethylene carbonate and diethyl carbonate as electrolytes for ion migration, while solid-state batteries mainly use solid oxides or sulfides as electrolytes.
The ultra-130kWh ultra-fast charging solid-state battery of Zhiji L6 will be coated with ultra-high nickel material with a patented nano-scale solid electrolyte for the positive electrode, and the negative electrode will be a new generation of high-specific energy composite silicon carbon material.
This sentence uses a very dense and complex vocabulary, which makes everyone confused. I'll break it down, and what it means is that they applied a "powdered (nanoscale)" electrolyte material to the cathode (cathode ultra-high nickel material) using a special process (coating process).
But what they don't say is that the battery still needs a liquid component to wet the electrode piece to facilitate the movement of electrons between the pole pieces. Isn't this still the working characteristic of electrolytes? Moreover, the mass of this "wetting agent" accounts for about 10% of the battery as a whole, which is about 5% lower than that of liquid lithium-ion batteries.
We can also do the side verification. It is no secret that this battery is a product of joint research and development with Qingtao Energy, and from its official website, there is an oxide solid electrolyte powder, which should be used on Zhiji L6. So it's not difficult to tell that Zhiji is really using a semi-solid-state battery.
Of course, if we're just obsessed with whether it's true solid, it's actually unfair to the product itself.
The energy density of ternary lithium batteries is usually 150Wh/kg~250Wh/kg, and the energy density of solid-state batteries can reach 1 times or even more than this data. For example, the solid-state battery unit equipped with the Zhiji L6 Max Light-Year Edition has an energy density of 368Wh, which is as high as 47.2% higher than 250Wh/kg.
Haobo solid-state battery data is very strong
But the test continues
Haobo clearly mentioned that their all-solid-state battery uses 100% solid-state electrolyte. Specifically, the third-generation sponge silicon anode and high-capacity solid-state cathode are used. It's a pity that Haobo didn't expand too much on the mystery of "high-capacity solid-state cathode".
According to the data released by GAC Aion in February, the energy density of the battery exceeded 350Wh/kg, and by April, this data was defined to exceed 400Wh/kg, which seems to be another breakthrough in the laboratory, and the energy density has increased by 60%.
Haobo can achieve 400Wh/kg, which is directly related to its high surface capacity of more than 5mAh/cm2 for the all-solid-state cathode.
According to Gu Huinan, general manager of GAC Aion, said in an interview with the "Securities Daily" reporter, their initial plan is to test the solid-state battery at the end of this year, and next year will mainly test the battery performance, and strive for mass production the year after tomorrow.
According to many experts, the innovation cycle of battery technology is about 30 years. Since 2000, lithium-ion batteries have been used in power, and it is expected that by 2030, all-solid-state batteries are expected to be industrialized. If GAC Aion can move forward smoothly, this speed will be four years earlier than expected.
However, GAC Aion cannot think that it can come out on top, and in 2023, BMW's main partner, Solid Power, has also released an all-solid-state battery with an energy density of 390W·h/kg. BMW hopes to launch its first prototype based on Solid Power battery technology by 2025, depending on who is faster.
In addition, since the all-solid-state battery production line is not compatible with the existing liquid battery production line, it would be too costly to invest directly in the all-solid-state battery production line. NIO has revealed that the price of a 150kWh semi-solid-state battery is close to 300,000 yuan. The high cost of products has become an obstacle on the road to the commercialization of solid-state batteries.
If GAC Aion uses the wet process, it can probably retain half of the existing equipment, and if the dry process is used, 2/3 of the equipment cannot be used, so it is necessary to realize the synchronization of equipment manufacturers.
Are "solid" and "semi-solid" incompatible?
Talking about this, everyone should have also discovered that their products are very good, and at the same time, they also have problems to overcome. I believe that "solid" and "semi-solid" are not incompatible, and it is more reasonable for each company to focus on its own advantages.
Why do we say this, we can look at several problems that need to be solved urgently from solid-state batteries.
(1) Cycle life attenuation and battery capacity
The mass production of solid-state batteries still has problems such as poor interface contact between solid-state electrolytes and high production costs. Due to the characteristics of solid-state electrolytes, the contact between the electrolyte and the positive and negative electrode materials will produce a large impedance, resulting in problems such as excessive loss and poor stability, resulting in the degradation of battery power and cycle life. Therefore, GAC Aion's follow-up experimental verification should spend a lot of energy here.
From another point of view, this is also the advantage of semi-solid-state batteries, injecting a small amount of liquid electrolyte into solid-state batteries can greatly increase the capacity of solid-state batteries and improve the problems of low energy and poor rate of solid-state batteries.
(2) Battery safety
Since there is no liquid electrolyte in solid-state batteries, the safety of the battery can be improved, which will be the advantage of GAC Aion's solid-state batteries.
However, the safety of semi-solid-state batteries is the key factor restricting their development, because the physical and chemical properties of semi-solid-state batteries are different from those of traditional liquid lithium-ion batteries, how to judge their safety performance and obtain the thermal runaway evaluation technology of power batteries with applicability is a problem that the industry needs to solve urgently. Therefore, if Zhiji wants to promote "semi-solid-state batteries", the key direction at this stage is here, such as launching more advanced BMS battery management technology.
summary
Because solid-state batteries use solid-state electrolytes, which are more stable and do not have the risk of liquid electrolytes being easy to burn and explode, solid-state batteries are considered to be an important representative of the next generation of high-performance lithium batteries compared with liquid batteries. But at the same time, semi-solid-state batteries should not be shouted by everyone, and there are many compromise advantages of this product at this stage.
In any case, good technology should be encouraged, and the batteries of both modes are very good, but car companies must be firm in their ideas, don't think about "sticking gold", and finally look unconfident, but not good. If you want me to say, Zhiji generously said that he uses semi-solid, but the product is difficult to play. GAC Aion said that it uses an all-solid-state state, but it will have to wait and see.