The top student must be diligent

"The experiment on carbon nanoporous materials, um... I'll leave it to you, Liu Xiaodong. You specialize in nanomaterials. I believe you should have some experience in this area."

Liu Xiaodong nodded immediately: "Okay professor!"

He is indeed engaged in nanomaterials. After just seeing the excellent properties of this new carbon nanoporous material, he already couldn't help but want to see it. Unexpectedly, Xiao Yi would now give this task to Got him.

"Then there are experiments on solid electrolyte doping and modification, which will trouble Tang Chunming and Chen Tao."

Both of them nodded.

The last sulfur electrode experiment was naturally handed over to Meng Hao.

Xiao Yi's assignments were basically in line with their past research directions, so they did not find it difficult.

As the tasks were assigned, the experiment officially began.

The task that Xiao Yi is responsible for is naturally to analyze and study their experimental results, and then use his own material mastery to conduct continuous simulations.

This also made Xiao Yi sigh in his heart. Sure enough, it would be more convenient to have someone under his command.

Otherwise, if he had to do so many experiments by himself, God knows how much effort it would take.

The four of them, Liu Xiaodong, were also very motivated and started the experiment immediately after receiving the task.

Maybe it’s because of my confidence in this subject, or maybe it’s because I can’t wait for those new high-end experimental equipment.

In this way, half a month passed quickly.

…

"Hmm...Is there no room for further optimization of carbon nanoporous materials?"

Looking at the experimental report in his hand, this report was completed by Liu Xiaodong. Regarding some further experiments on carbon nanoporous materials, Xiao Yi groped his chin. Under the vision of material mastery, he went through different simulations and could not find it. to the point where optimization can continue.

"Perhaps this material has reached its limit, or it is still a little short of the theoretical limit."

Xiao Yi shook his head.

Of course, the current carbon nanoporous material is already very good, whether it is in terms of ionic conductivity or interface resistance. In addition, it also has an inhibitory effect on lithium dendrites, which is also very good. the point.

"Then this material will be ready as it is."

"Then there is the sulfur electrode... Indeed, it is completely undesirable to use simple sulfur as an electrode."

"The carbon sulfide cathode...has great potential."

"Then just try the carbon sulfide anode."

With the activation of material control capabilities, the field of vision entered the microscopic view of sulfur electrode samples.

Xiao Yi has now gradually become accustomed to this spectacular and magnificent microscopic world. Without too much surprise, he directly started to simulate changes to the internal structure according to what he thought.

The carbon sulfide cathode in lithium-sulfur batteries does not refer to CS2. Strictly speaking, it should be an S-C composite material, which can improve the conductivity and utilization of sulfur while strongly inhibiting the shuttle effect of polysulfides. In lithium Sulfur batteries have always been the focus of research.

However, after some simulation, Xiao Yi always felt that there was a lot of difference.

"After many cycles, the quality of this type of electrode will always deteriorate and it is not easy to use."

After the battery is fully charged and discharged many times, the electrodes will gradually degenerate, resulting in poor performance, and ultimately the battery capacity will be reduced.

Just like a mobile phone battery, the performance of the battery will deteriorate because it is used for too long. This is reflected in the situation that the mobile phone may lose 10 cells of electricity in 10 minutes.

Therefore, it is also important to ensure that the performance of the electrode does not deteriorate so easily, which places very high requirements on the design of electrode materials.

Xiao Yi pondered, and his heart suddenly moved.

"What if some N elements are doped into it? Use high molecular polymer materials and then vulcanize!"

Xiao Yi searched for various related nitrogen-containing polymers in his mind, and finally, the name of a material appeared in his mind: "Vulcanized polyacrylonitrile!"

His eyes soon lit up.

As his mind moved, the S-C composite material under the material control field of view was also simulated as vulcanized polyacrylonitrile.

Soon, its superior performance immediately made Xiao Yi's eyes light up.

High active material utilization and almost 100% Coulombic efficiency, excellent reversibility and cycle stability...

This new sulfide carbon material immediately attracted all his attention.

At the same time, with its continuous optimization, this new material has gradually shown more and more superior performance.

Until finally, he once again successfully determined what should be the best structure of vulcanized polyacrylonitrile.

Soon, he withdrew from the perspective of material mastery and recorded various key points about vulcanized polyacrylonitrile. He then sent these key points to Meng Hao, who was in charge of S-C composite materials.

The next question is how to synthesize vulcanized polyacrylonitrile with this structure.

However, for Xiao Yi, who has mastery of the materials, he only needs to continue experimenting, and he will eventually be able to find the correct synthesis method.

Since then, two of the three key technologies, carbon nanoporous materials and sulfur electrode problems, have basically been solved.

The final question is.

"Interface modification of lithium phosphorus sulfur chloride."

Xiao Yi narrowed his eyes.

I took a look at the experimental reports of Tang Chunming and Chen Tao, but the results of these experiments were not ideal.

And even if you use the materials to master it, it feels like you don’t know where to start.

I think that whether it is compared to nanoporous materials or sulfur electrodes, solid electrolytes are far superior in complexity.

It involves many complex fields such as ion conduction mechanism, material synthesis, and interface engineering, and requires comprehensive interdisciplinary research and multi-faceted optimization.

Xiao Yi closed his eyes and began to synthesize all relevant knowledge in his mind.

After about a few minutes, he opened his eyes again.

"Now that we have researched it to this point, it is nothing more than coming up with another theory."

"Then come on!"

…

Chapter 198 Electronic Interface Reaction Migration Model

Chapter 198 Electron-Interface Reaction Migration Model

After all, it is impossible to easily develop solid-state lithium-sulfur batteries.

As far as the current theories in the scientific community are concerned, there are still quite a few things that are not understood about solid electrolytes.

Especially some processes that occur on the interface.

And [interface] is also a common concept in chemistry and physics.

An interface usually refers to the boundary or contact area between two different phases, such as the area of ​​contact between any different phases, substances or materials.

This concept exists between various combinations of solids, liquids, and gases.

Especially in the battery field, electrodes and electrolytes are different materials, and different materials have different properties.

So at the interface, these differences will lead to gradient changes in physical and chemical properties, such as differential changes in electric potential, concentration, structure, etc.

Naturally, different problems arise for the interfaces between different materials.

"However, although these materials appear to be different, the ultimate problem is only reflected in the electrons."

In the office, Xiao Yi lowered his head and thought.

It's like the absolute electronic principle he once developed.

Weak force, strong force, and gravity have nothing to do with materials. Under daily life and routine experimental conditions, the essence of materials is electromagnetic interaction force.

"It is quite appropriate to use the principle of absolute electronicity to calculate the migration of electrons and ions at the interface, but it lacks some pertinence."

The pen in his hand kept writing on the draft paper until finally Xiao Yi shook his head.

"The original calculation of absolute electronic properties only considered relatively simple situations, mainly focusing on the same kind of materials. It was indeed somewhat inadequate for this kind of interface problem that occurs between two complex materials."

"There is a lack of a theory that simply simplifies interface problems..."

"Well, there is currently a space charge layer theory, but it is not perfect yet."

"Also, there are some related concepts."

Xiao Yi narrowed his eyes slightly, and then wrote various related concepts on the draft paper.

Space charge layer, interface resistance, interface capacitance, interface interdiffusion model...

How to combine various different concepts?

Suddenly Xiao Yi's eyes moved and he focused on the interface mutual diffusion model.

"By the way, the reaction-diffusion equation!"

【u/t=D^2u+R(u)】

I wrote this formula on the scratch paper.

This is a partial differential equation, similar to the NS equation. The NS equation can describe various behaviors of molecules in a fluid, while the reaction-diffusion equation is used to describe the diffusion and reaction processes of chemical substances in the system.

Similarly, it can also provide a good description of the ion migration process occurring at the interface.

Xiao Yi's eyes brightened slightly and he started to deduce on the draft paper.