The Science Fiction World of Xueba

One week later, Jiangcheng University officially announced the establishment of a lithium-air battery research team, with Pang Xuelin as the team leader and Kirton Walker as the deputy team leader.

At the same time, Xinkai Material Technology Co., Ltd. announced that it will provide 100 million RMB in capital support for the lithium air team.

In addition, Pang Xuelin took his villa in Binjiang as a mortgage, and obtained a low-interest loan of 50 million from the bank.

I think it is enough to make up 150 million RMB.

Next, what Pang Xuelin wants to do is to make a prototype of a lithium-air battery in the laboratory.

At this time, in the conference room of the School of Chemistry and Molecular Engineering of Jiangcheng University, in addition to Pang Xuelin and Kirton Walker, there were six or seven scholars transferred from the School of Materials Engineering and the School of Chemistry and Molecular Engineering.

These people were basically recommended by the school, and after a joint interview with Pang Xuelin and Kirton Walker, they were approved by the two to join the lithium-air battery project.

The outside world is not optimistic about the lithium air battery project team.

At this time, Peng Xuelin and Tian Hong's gambling agreement on lithium air batteries also passed abroad.

Foreign media taunted that the actions of Pang Xuelin and Kirton Walker were just another technical scam.

Even many well-known scholars in the field of lithium batteries have come forward to say that although lithium-air batteries have good prospects, the current research is still quite elementary, and there are still many scientific and engineering challenges to be solved. It takes at least ten years.

The reason why Pang Xuelin and Tian Hong bet that lithium-air batteries were produced within half a year was only due to the fate of face.

However, these scholars who joined the lithium-air battery team were not affected by much public opinion, but were eager for the next research.

的 Contacts made by Pang Xuelin during the past week have made them realize that Pang Xuelin and Kirton Walker's attempts in the field of lithium air batteries are not trivial, but they are really possible.

Moreover, the 150 million yuan invested by Pang Xuelin also made them full of confidence in the next research plan.

Pang Xuelin sat at the top of the meeting room, looked at the crowd, smiled, and said, "The first meeting of all members of the lithium-air battery project started now. Today we will work on the specific implementation route of the lithium-air battery and the division of labor. Detailed task allocation plan. "

Pang Xuelinton paused and continued: "With the development of science and technology, energy shortages are becoming an urgent problem to be solved. So people are paying more and more attention to environmentally friendly batteries with high energy storage. The research of batteries has developed from Ni-MH to the present Lithium secondary battery. Lithium secondary battery has a high volume ratio, energy ratio, and mass ratio. There is no memory effect of Cd-Ni sintered batteries. There is no problem of battery capacity loss. The battery does not contain lead, cadmium, mercury, etc. Harmful substances are called green batteries. Therefore, lithium secondary batteries have become a research hotspot in the world today due to their obvious advantages such as high energy density, long cycle life, and green and pollution-free. "

"Lithium-air batteries, among lithium secondary batteries, are among the most advanced. However, lithium-air batteries also have the following problems."

"The first is the lithium crystal branch problem. As we all know, lithium air batteries generally use lithium metal as the negative electrode material. When the lithium metal is charged, the surface of the lithium battery is unevenly distributed due to the unevenness of the surface of the lithium electrode, causing lithium to be uneven. Uniform deposition. This uneven deposition process causes lithium to deposit too quickly in some parts, resulting in dendrite-like crystals, that is, lithium dendrites. When the lithium crystals develop to a certain degree, there are two consequences, one is that the crystal branches break. The phenomenon of dead lithium results in irreversible lithium; another consequence is more serious. The crystal shoots pass through the diaphragm and connect the positive and negative electrodes to form a short circuit in the battery. As a result, a large current is generated, a large amount of heat is generated, and the battery is on fire due to the sharp rise in temperature , Or even an explosion, creating serious safety issues. "

"Second, the problem of moisture and nitrogen control in the air. Lithium-air batteries are an open system, which is different from lithium-ion batteries. Lithium-air uses oxygen in the air, and the air contains nitrogen and water vapor. Lithium Will react with both of them. It is a difficult problem to solve both oxygen and nitrogen and waterproof. "

"Third, the problem of solid reaction product accumulation. Because lithium-air batteries use oxygen in the air as the active material on the positive electrode, the theoretical capacity density of the positive electrode is infinite, and the capacity can be increased. In addition, if the negative electrode uses metal lithium, The theoretical capacity will be one digit higher than that of a lithium-ion rechargeable battery. However, lithium oxide (Li2O), a solid reaction product, will accumulate on the positive electrode, which will block the contact between the electrolyte and air, causing the discharge to stop. "

"Fourth, the catalytic reduction of oxygen. The reaction speed of oxygen is very slow. To improve the reactivity of oxygen, an efficient catalyst must be used. The current catalysts are all precious metals. Therefore, it is necessary to develop efficient and cheap catalysts, which has always been a constraint. The shortcomings of fuel cell development. "

"These four issues will be urgent problems that we need to solve in the next six months."

目前 "At present, on these issues, we mainly have the following ideas."

"First, the lithium branch problem. At present, there are two main solutions to the lithium branch problem in the world. The first one is to use heavy magnesium carbonate (trifluoromethanesulfonyl) as an electrolyte additive. Subsequently, the accumulated lithium undergoes an alloying reaction. The second is to use a 3D polydimethylsiloxane (PDMS) layer or a silicone resin layer as a substrate for the lithium metal anode to ease the formation of lithium crystals. There are more or less problems in the solutions. Therefore, I consider that large-size single-layer graphene films are covered on the surface of lithium metal, thereby suppressing the formation of lithium crystals. As for how to allow graphene films to cover the surface of lithium metal, This problem was left to the joint team of Professor Ye Xingmin and Professor Huo Ziqian! "

教授 "Professor Pang, rest assured, we promise to complete the task."

Ye Xingmin and Huo Ziqian both nodded and agreed.

两位 Both are from the School of Materials Engineering. Ye Xingmin joined Pang Xuelin's research team last year and played an important role in the process of preparing high-purity single-walled carbon nanotubes in the laboratory.

Later he was transferred to the Flying Blade Materials Project Team by Pang Xuelin, and the rank was also upgraded from a former associate professor to a professor.

At present, the flying blade material project is progressing smoothly. Pang Xuelin simply brought Ye Xingmin to the lithium air battery project team.

Ye Xingmin and Pang Xuelin have cooperated for the longest time. They have already taught Pang Xuelin's academic level before. Therefore, among the people present, Ye Xingmin has the most confidence in Pang Xuelin.

As for Huo Ziqian, he is an expert in the field of graphene materials. Pang Xuelin proposed the large-size single-layer graphene material preparation and industrialized production scheme, which has long surprised him.

This time Pang Xuelin invited him to join the lithium air battery project team, and he readily agreed.

Pang Xuelin smiled slightly, took the tea cup on the table and took a sip, and continued: "The second problem, the control of moisture and nitrogen in the air, this problem must be solved together with the accumulation of solid lithium oxide reaction products. After discussions with Professor Wharton, I have the following scheme: The organic electrolyte for the negative electrode uses a lithium salt-containing organic electrolyte. Although the organic solvent cannot be discarded, the use method is limited. Use of the aqueous electrolyte for the positive electrode Alkaline water-soluble gel, combined with a positive electrode formed by miniaturized carbon and a low-cost oxide catalyst. In lithium-air batteries, solid lithium oxide is not produced by the discharge reaction, but is easily dissolved in aqueous electrolyte. (Lithium hydroxide). Lithium oxide will not stop working after the air electrode is deposited. Water and nitrogen will not pass through the solid electrolyte barrier, so there is no danger of reacting with the lithium metal of the negative electrode. "When charging, if equipped with a dedicated positive electrode, it can also prevent corrosion and aging of the air electrode caused by charging."

"The only problem now is how to make the organic electrolyte containing lithium salt in the negative electrode and the aqueous electrolyte used in the positive electrode do not interfere with each other and get along harmoniously. At the same time, it is necessary to ensure that lithium ions shuttle between these two electrolytes Our method is the same as before, using a large-sized single-layer graphene material as a shielding layer between the two electrolytes. And I have calculated that the six-membered carbon ring of graphene can just allow lithium ions Going through this channel, as long as we verify this in experiments, the biggest technical problem in lithium-air batteries will be solved. "

"Therefore, this problem will be solved by Professor Kirton Walker and Professor He Wenyan."

Xi Pang Xuelin's words fell, except for Kirton Walker, who already knew the inside story, and everyone else was surprised.

Even those professors from the School of Chemistry and Molecular Engineering who first collaborated with Pang Xuelin for the first time showed a stunned expression on their faces.

No wonder Pang Xuelin dared to make this bet with Tian Hong, the key point turned out to be here.

庞 When Pang Xuelin talked with them before, although some information was revealed, it was far from detailed this time.

They did not expect that Pang Xuelin and Kirton had a complete idea to solve the problems of nitrogen, water reaction and solid product accumulation in lithium-air batteries, and even had specific implementation plans.

However, they will not talk about it. The main members who joined the project team have signed confidentiality agreements, and the penalty is even higher.

人 No one will joke about his future.

At this time, a professor named Qiu Qiwei from the School of Chemistry and Molecular Engineering praised: "Professor Walker, no wonder Professor Pang is willing to invest in your project. It turns out that you have such a clever solution."

Kirton Walker shook his head with a bitter smile and said, "Professor Qiu, you are wrong, the designer of this solution was not me. When I first found Professor Pang, I just felt that graphene materials had a certain potential. It can be applied to the field of lithium-air batteries, but how to realize it, I still obliterate it. This solution was proposed by Professor Pang Xuelin, and even the previous theoretical calculations were independently completed by Professor Pang Xuelin. We need to do next Yes, I repeat Professor Pang Xuelin's ideas. "

Corton Walker's voice dropped, and everyone in the room couldn't help looking at each other, stunned.

Ye Xingmin, who has been in contact with Pang Xuelin for the longest time, responded slightly flatly.

This has always been the routine operation of Professor Pang.

He Wenyan aside, exclaimed, "Professor Pang, do you still have research in the field of lithium-air batteries?"

Pang Xuelin smiled lightly: "In fact, Professor Walker did not look for me about lithium-air batteries. I already had some ideas before, but Professor Walker found me and said that he used large-sized single-layer graphene as a half-way between the positive and negative electrodes. The transmembrane is inconsistent with my thoughts, so I brought Walker here. Well, there are some points, but they are all immature thoughts. When I studied mathematical conjectures before, if I did not go well or did not have ideas, I would I read a lot of miscellaneous papers. I read a review of lithium-air batteries before, and I think this kind of battery is quite interesting. So I put together some messy ideas before, and everyone laughed. "

He Wenyan looked strangely at Pang Xuelin.

He didn't have much contact with Pang Xuelin, and his understanding of the young genius was limited to praise from others and reports in the news.

Before Pang Xuelin worked on carbon nanomaterials, and recently came up with artificial intelligence MOSS, these are already amazing.

I didn't expect the other party to have such profound accomplishments in the field of lithium air batteries.

The expressions on other people's faces are similar to those of He Wenyan. Since contacting Pang Xuelin for a week, they all have the feeling of meeting Professor Pang for the first time.

Pang Xuelin smiled: "Well, next, let's talk about the fourth question, how to increase the reaction speed of oxygen and lithium metal. Generally, we will use precious metals as catalysts, but considering mass production and future costs The problem is that we need to find a relatively cheap metal catalyst. According to my previous theoretical calculations, we can consider choosing among metal cluster catalysts. Everyone knows that the chemical characteristics of the clusters show the atoms or molecules that follow the clusters. The increase of the number n results in the characteristics of parity oscillation and magic number. The difference of the reaction rate constants of metal clusters at different values ​​of n can reach 10 ^ 3. Regarding the catalytic performance of metal cluster catalysts, the homonuclear and heteronuclear Cluster compounds as catalysts have higher activity and selectivity in redox reactions ~ www.readwn.com ~ This question is left to Professor Qiu Qiwei and Professor Xu Ting! "

After Qiu Qiwei and Xu Ting heard the words, they both nodded and agreed.

Pang Xuelin said: "About the general technical plan and route of lithium-air batteries, that's all, do you have any questions?"

At this time, Xu Tingdao, who had not spoken before, said: "Professor Pang, if we use a metal cluster catalyst, where is the catalyst suitable? If it is placed directly in an alkaline water-soluble gel, it may cause oxidation. Lithium accumulates on its surface, which affects the charging effect and service life of the electrolyte. "

Pang Xuelin smiled and was prepared for this problem, saying, "It's very simple, we can fix it directly to the air electrode material made of graphite. This way, not only will it not affect the electrolyte, but it will also pass Change the cathode material regularly to solve the problem of solid reactant accumulation! "

Xu Ting nodded and said, "Professor Pang, I understand."

好 "Well, do you have any questions?"

Xi Pang Xuelin looked around.

Everyone looked at each other and said, "Nothing!"

"No problem."

"I think the current solution is perfect. Next, let's see how the experiment works. When problems occur again in the experiment, we can discuss and solve them at that time."

Xi Pang Xuelin nodded: "Okay, so that's it, let's go away, and then officially start entering the project process!"