Graphene is praised as "the king of new materials" by researchers and major media. It is a new nano-material with high strength, good toughness, light weight, high transmittance and good conductivity.

Graphene polymer battery has the advantages of high specific energy and fast charging speed, which is the pain point of today's electric vehicles. For example, as early as 20 15, Huawei Watt Lab released a fast charging technology at the 56th Japan Battery Conference in Japan. This 3000mAh graphene battery can get up to 48% power in just 5 minutes.

What's more, as early as 20 14, Spain's graphene nano company cooperated with the University of Có rdoba in Spain to develop the first graphene polymer battery.

According to them, this kind of battery has many advantages:

1. The specific energy of a graphene battery exceeds 600wh/kg, and its storage capacity is three times that of the best products on the market at that time. Such performance can be crushed today (for example, the single energy density of BYD lithium iron phosphate battery is 150~ 160Wh/kg, and the energy density of Tesla's latest 2 1700 battery system is 300 Wh).

2. The single cruising range can be as high as 1000 km;

3. The single cruising range can be as high as 1000 km;

4. It only takes 8 minutes to fully charge once;

5. The service life is 4 times that of the traditional hydrogenated battery and 2 times that of the lithium battery;

6. The weight is only half of that of a traditional battery;

7. Graphene Nano said that the cost of this battery is 77% lower than that of lithium battery.

From the laboratory point of view, these data are not doubtful, because graphene batteries are also called "money-making tools" or "paper-making tools". If you don't believe me, just go to the university and have a look. It is easy to publish an article on this thing, but when it comes to practical stage, it is basically dumb.

It is easy to verify whether this is deliberately belittling graphene batteries. For example, it has been four years now, and graphene nano has never appeared in our field of vision.

From official website, the latest news is basically attending national conferences or the application of graphene in other products (such as dental products). Don't make money from medical supplies when the electric vehicle market is vast, either we are crazy or we overestimate their products.

In fact, the "graphene battery" currently claimed on the market is an inaccurate concept. To be precise, it is basically to add a little graphene to the material to improve some properties of lithium batteries, which can be called graphene-based lithium-ion batteries.

For lithium-ion batteries, graphene, as a carbon-based anode material, has no way to fundamentally change the energy ratio of lithium-ion batteries.

Replacing the original graphite in the battery cathode can improve the overall capacity and charging speed of the battery, but the performance improvement effect is limited, not as strong as mentioned above.

Of course, this is not the main reason that hinders the listing of graphene batteries. The main reasons for the difficulty in mass production are internal:

1. All-graphene battery is very expensive and difficult to prepare, and it is almost impossible to mass-produce. Some amazing data published now are basically from high-purity graphene batteries, which only appear in the concept stage or in the laboratory;

2. The function of "doped graphene battery" in lithium battery is that the conductive agent or electrode is embedded in lithium material, but compared with the low cost of traditional conductive carbon and graphite, the performance improvement brought by the former is not enough to attract manufacturers;

3. Graphene material itself has the characteristics of high specific surface area, which is incompatible with the current technical system of lithium ion battery industry;

4. In addition, for example, the influence of other materials (for example, silicon as a negative electrode has a higher theoretical capacity) and the difficulty of dispersion process limit its application in lithium batteries.

In short, the first thing to note is that graphene batteries are basically impossible to replace lithium batteries in the short to medium term; Although "doped graphene lithium battery" has a certain application prospect, its function is not great enough to shake the current pattern.

Li Yangxing, chief scientist of Watt Lab, once said: Graphene lithium battery technology mainly solves three problems:

First, special additives are added to the electrolyte to avoid its decomposition at high temperature;

Secondly, the large single crystal ternary material is selected as the anode to enhance the thermal stability;

Thirdly, the addition of graphene achieves efficient heat dissipation.

In addition to the high price of graphene, it can't be mass-produced. Can you find substitutes in the current new material market?

According to the research, zirconium phosphate (ZrP) is an inorganic layered compound with good proton conductivity and an excellent water-retaining material. In recent years, it has been reported that ZrP is doped into Nafion to prepare proton exchange composite membrane, and it is pointed out that ZrP improves the water retention and battery performance of the membrane. However, ZrP, as a proton conductor, can not be used in the field of proton exchange membrane alone. Therefore, it is an effective method to prepare organic-inorganic composite membrane materials by choosing a polymer with low cost and good performance as an organic matrix and fixing inorganic ZrP particles in the organic polymer. Among non-fluorinated hydrocarbon polymers, polyimide (PI) is an excellent choice for ZrP carrier because of its good thermal stability, excellent chemical resistance and mechanical stability, low cost and good film-forming property.

The study of membrane properties shows that the thermal stability and water retention of the composite membrane are improved by doping ZrP. PI/ZRP proton exchange composite membrane can maintain a low swelling degree, and the water content and swelling degree of PL/20% ZRP composite membrane are 39% and 3.9% respectively. The proton conductivity of PI/ZrP proton exchange composite membrane increases with the increase of ZrP doping amount. PI/ZRP proton exchange composite membrane can provide a stable proton transport channel at 90℃. C in the environment with relative humidity of 100%, the proton conductivity of the PI/20% ZRP composite membrane reaches 3.6 1× 10-? Ms. cm- .

Since zirconium phosphate can occupy a place in proton exchange membrane fuel cells, it will inevitably have super applications in the field of lithium batteries. When this technology is mature, zirconium phosphate, as a new material with mass production and controllable cost, will definitely solve the remaining problems of graphene temporary storage and promote the development of battery industry!