Graphene battery is coming, is the new technology really awesome? Is lithium battery a blessing or a curse?

The hottest financial event on the weekend was GAC's "graphene" battery. The media claimed that "you can run 1000 km with 80% charge in 8 minutes". This "explosive" news directly led to the change of the new energy vehicle+graphene plate at the end of Friday, and there were many voices of doubt over the weekend. On the forum of China Electric Vehicle Committee of Chinese Academy of Sciences 100 (202 1), with the present technology, he must be a liar. "

Since the release of 150kWh solid-state battery by Weilai Automobile last week, the whole new energy battery sector has been frightened. If this "graphene" battery is another technological leap, are some lithium battery stocks cold? This is what investors are most worried about (many people in the new energy sector have heavy positions, and everyone would rather believe that the "graphene" battery is a complete scam). I also looked up a lot of information over the weekend, and the conclusion may be different from everyone's. Let me share my research with you:

1, the media over-interpreted, in order to attract attention, there is no bottom line to improve the technical level.

The official original text of GAC said: "GAC graphene-based super fast-charging battery has entered the stage of mass production testing of real vehicles. The first model is AION V, which is initially planned for mass production in September this year. " See the difference? The original text is graphene-based ultra-fast rechargeable battery (graphene-based battery), which is not equal to graphene battery.

I learned about graphene from my brother who is engaged in material research at my alma mater. In fact, graphene is composed of carbon molecular network structure, and graphene material is very thin, so it can't store electric energy. Mainly used to separate the two poles of the battery, electrons can easily pass through, that is, the internal resistance of the battery will be very small, which is why it charges and discharges quickly. The main advantages of graphene battery are service life and charging speed. At present, the "graphene battery" generally studied refers to the application of graphene material to the negative electrode of the battery, and the storage and release of electrochemical energy is still realized by the migration, deintercalation or combination of lithium ions in the battery. Because the application of graphene material has not fundamentally changed the performance of the battery, the main material system of this kind of battery has not changed. The positive electrode is ternary, lithium ferrous phosphate or manganese, the negative electrode is graphite or metal oxide, and there are electrolyte and diaphragm. So why did Guangzhou Automobile Group's share price change last Friday, and lithium batteries didn't plummet like solid-state batteries?

2. Charging for 8 minutes and traveling around China?

For fast charging, it will quickly consume the cycle life of the battery and bring potential safety hazards, which will be more serious at low temperature or high temperature. It takes 8 minutes to charge 80% of the electricity, and the charging power must be very high. In this way, all components of the circuit, including external charging piles and car charging systems, will be difficult to carry such huge power. So is this really a lie? Not right either!

As early as May 13, 2020, the new energy department of Guangzhou Automobile Group announced that the research and development of graphene battery mass production will move from laboratory to real vehicle, and the related graphene battery technology achievements will be carried on some models of Guangzhou Automobile New Energy Vehicle Ai 'an at the end of this year. The results show that this kind of super battery can not only "charge the battery to 85% within 8 minutes", but also meet the service standard in life and safety. Look! It's very modest for people to charge 80% for advertising for eight minutes. Last year, it was 85%.

Moreover, it is not only Guangzhou Automobile that has this technology. Official website, the University of Science and Technology of China, reported that the new black scale lithium battery developed by Chinese and American scientists can charge 80% of the electricity in 9 minutes. The electrode sheet based on black scale composite material has excellent performance. The test shows that it can charge 80% electricity in 9 minutes, and it still has 90% charging capacity after 2000 cycles. With these properties, if this new material can be mass-produced, it is expected to manufacture a fast-charging lithium electronic battery with an energy density of 350 WHr, and the mileage of electric vehicles can reach 1000km.

Curious friends will ask, why when it comes to the charging efficiency of electric vehicles, it is often the time required to charge to 80% capacity, not full?

It turns out that battery charging is staged, from 0% to 90%, which is constant current charging, that is, the voltage increases with the increase of battery voltage. Then enter the constant voltage charging mode, the voltage is slightly higher than the final voltage of the battery, and the current will gradually decrease. Finally, the trickle charging mode is entered, and the small current maintains the charging state, and the charging is from 0% to 80%, and the battery loss is less. When charging to 100%, the battery loss will double. Simply put, the battery capacity will be fast from 0% to 80%, and then it will take longer from 80% to 100%. Therefore, it is not subversive to charge 80% of the results in 8 minutes.

3. Will you charge it quickly?

In fact, whether fast charging or slow charging, we must abide by the law of conservation of energy, and it is impossible to generate energy out of thin air, which means that fast charging must be equipped with charging piles with high power and high current. The advantage of fast charging is very simple, and the charging speed can be much faster. The disadvantage is that the battery is seriously heated, which will affect the life of the battery pack, and the excessive charging current of the lithium battery will also cause gas accumulation and other problems. Ordinary charging can effectively extend the battery life. At the most advanced level, if only fast charge is used, the battery life is about 3 years. If the same battery is charged normally and recharged when it is half full, its service life can be doubled to 5-6 years. Moreover, every time a lithium battery is fully charged or discharged (within the normal range), it will aggravate the lithium precipitation (irreversible chemical change) of the anode and cathode, and will also affect its service life.

To sum up, I don't think Guangzhou Automobile Group's new products are bragging, let alone liars. After all, the people's government is ready for mass production, but it is not as magical as everyone thinks, and there are subversive technologies to be born (if it is really awesome, the company's share price can't have been shown for half a year), and its essence has not got rid of the big framework of lithium batteries, not to mention the life of lithium battery technology, so investors don't need to worry too much about this news.

Finally look at Friday's market data. The index seems to fluctuate within a narrow range. In fact, there is a deep V rebound in Shenzhen. Is this deep V rebound a signal to stop falling? Please see the following for the specific interpretation:

data analysis

1. Overall data analysis: 226 stocks fell by 3%, 94/kloc-0 stocks rose by 3%, and 75 entities had daily limit. On that day, they had a daily limit of 1 1 stock, with long strength of 503 and short strength of 240, belonging to the box vibration system (day 8).

2. Position reference: The overall market mentality is 33, which belongs to a low mentality and the position is in a shock cycle. The computer suggested that the total position should be maintained at 6.8% tomorrow.

3. In terms of hot spots, the number of the top five outlets is 4-22, and the main outlet is new energy. The core leader of the market is Yibin Paper, with 8 grades and concept papermaking.

4. Short-term analysis: Judging from the success rate of board chasing, today's success rate is higher. From the point of view of individual stocks, the yield of bursting board is high, the yield of closing board is poor, the yield of listing is poor, and the graphics are intertwined horizontally, which shows that the views are chaotic and the short-term trend of powerful stocks is disorderly.

5. intraday hot spot tracking: no plate continuation (it is rare to have no relay)

09:27 Bank -09: 34 Nonferrous -09: 40 Coal -09: 45 Bank-13: 38 Lithium Battery-14: 22 Automobile-14: 35 Graphene.

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Exponential point of view: From the statistical data, the system is located in the shock box area (data 1), with a slight decrease in positions (data 2), short-term tuyere new energy, no continuation board (data 3 and 5), high success rate of board sealing and poor yield (data 4). There are many cases where the data is not as good as expected: the strength in data 1 has not turned red, the hot spots in data 4 have obvious loss effect, and data 5 has not continued. Combined with the wide fluctuation of the index, it rose slightly and fell slightly, and it felt that the strength of doing more was weak. From the data point of view, the market has stepped into a volatile market from a rising market, and the strategy of selling high and sucking low has more market than blindly watching more or bearish. Before finding the market peak signal, we can try the band interval operation strategy.

To sum up, it is recommended to lighten the positions on rallies for the sectors that have risen within the range, and to absorb on dips for the sectors that have fallen too much within the range, that is, the oversold rebound sectors that have recently increased too much. You can implement a high-throwing strategy, and the group plate that has fallen too much recently can also try to absorb on dips.