Following NIO's solid-state battery, GAC has once again pushed the controversy surrounding new power battery technologies to a new level.
According to an official poster released by GAC Aion last Friday, models equipped with graphene-based super-fast charging batteries can be charged to 80% in 8 minutes, with an NEDC range of 1,000 kilometers.
The following day, Ouyang Minggao, an academician of the Chinese Academy of Sciences, stated at an industry conference: "If someone tells you that this car can run 1,000 kilometers, can be fully charged in a few minutes, is very safe, and has a very low cost, then with current technology, they are definitely a fraudster."
A heated debate is currently unfolding surrounding graphene battery technology. How should we understand "graphene batteries" from a technical perspective?
First, we need to clarify what a graphene battery is. This starts with the industry's naming conventions. It's understood that in the power battery industry, the general rule is to define the battery by the component that plays the most significant role. Since the performance of a power battery is most closely related to the cathode material, it's usually named after the cathode material, such as ternary lithium batteries, lithium iron phosphate batteries, and lithium manganese oxide batteries.
In this sense, the term "graphene battery" should mean a battery whose cathode material is mainly graphene.
According to GAC, the technology is officially called "graphene-based super fast charging battery." Although it only has one more word "based," it is quite different from the so-called "graphene battery."
The correct name for GAC's so-called "graphene battery" should be "silicon-based negative electrode lithium battery doped with graphene." This battery technology aligns more closely with the general trend of graphene's commercial application in batteries in recent years.
In 2016, Dongxu Optoelectronic announced the launch of the world's first graphene-based lithium-ion battery product, "Xiwang". Subsequently, Huawei also announced the launch of the industry's first high-temperature, long-life graphene-based lithium-ion battery. Last August, Xiaomi's Xiaomi 10 Ultra also claimed to use a new graphene-based material battery with built-in third-generation conductive agent graphene, whose conductivity is 1,000 times that of traditional carbon black materials.
In the three examples above, the term "graphene-based" refers to using graphene as a conductive agent in the battery, rather than using graphene as a positive electrode material. Therefore, it can be roughly inferred that GAC's "graphene-based super fast charging battery" is also a lithium battery that uses graphene as a conductive agent, and the correct expression should be "graphene-based lithium battery".
Furthermore, GAC's emphasis on "super fast charging" also indirectly illustrates the role of graphene as a conductive agent in its batteries—the stronger conductivity results in faster charging speeds. It's important to clarify that graphene-based lithium batteries improve charging speed, not driving range; they represent another crucial means of alleviating consumers' "range anxiety."
Secondly, it's important to understand the technological direction of integrating graphene into batteries. Graphene possesses characteristics such as thinness and high hardness, and its emergence has brought the possibility of breakthroughs in high performance, high capacity, high rate of change, and long lifespan for lithium-ion batteries.
To integrate graphene technology into the battery industry, there are two main directions: one is as a conductive additive, and the other is as a negative electrode material.
If graphene is used as an anode material, its high cost will be a significant barrier. Analysis suggests that if graphene is used as the main anode material in power batteries, the cost of electric vehicles will be extremely high; however, if it is used as an additive, the cost will be acceptable.
However, if used as a conductive additive, it is still essentially a lithium battery. Furthermore, graphene cannot achieve superconductivity at room temperature, and compared to cheaper additives, it does not offer much advantage.
Finally, it's important to clarify the challenges of mass-producing graphene. Graphene preparation is quite complex, and its cost is significantly higher than that of conventional graphite, and even the widely favored silicon anode. Furthermore, ensuring the stability of graphene across multiple batches is much more difficult.
Solving problems such as low-cost, high-quality graphene preparation and graphene blocking lithium-ion channels has become a crucial issue for the commercialization of graphene batteries. Furthermore, many challenges remain before they can be successfully implemented in mass-produced vehicles.
