Lu Zhou replied, "I'll come." ”

The system doesn't specify who has to run the experiment, just do the experiment and collect the data that needs to be collected. However, not for the purpose of learning, Lu Zhou still wanted to do it himself.

After all, the paper is shallow, and the books handed to him are all theories, and only by implementing them in his hands can he turn the legendary black technology into a real guy.

Changing into a white coat with a sense of ceremony, Lu Zhou took out a little bit of the momentum of a scientist, took a deep breath, and reached for the sample box containing the experimental materials.

However, before he could touch his hand, he was snatched away by Senior Brother Qian, who was quick-eyed.

"I'll do it while I watch."

Without saying a word, Senior Brother Qian took over the initiative of the experiment and left Lu Zhou, who looked confused, to the side.

Looking at Senior Brother Liu, Senior Brother Liu, who was holding his arms, shrugged helplessly.

"Don't mind, Lao Qian is like this, the equipment here is like his wife, more important than his life...... The first time, you'd better watch him do it again. ”

Senior Brother Qian didn't look back, and then said: "Doing experiments is not doing mathematics, you can continue to calculate if you make a mistake and change a decimal point, and if you make a mistake in an experiment, a small detail may lead to the entire experiment being wasted." Of course, I'm more afraid that you will scrap the experimental equipment...... Show me the experimental process you designed. ”

"Here." Lu Zhou quickly took out the A4 paper.

He wrote down the experimental procedures required by the system and the experimental data that needed to be collected.

Senior Brother Qian took the A4 paper and glanced at it, and nodded: "The design is quite professional." ”

emmm……

After all, it is the system design.

Lu Zhou's expression was subtle and he didn't speak.

……

The process of the experiment is simple, starting with the making of the battery and ending with the observation of the phenomenon.

95.7% graphite is used as the anode material, the binders are sodium carboxymethyl cellulose (CMC) and styrene-butadiene rubber (SBR), and the current collector is copper foil. The thickness of the graphite layer is 90 μm, the cathode active material is LiFePO4, and the current collector is aluminum foil.

As for the diaphragm, a three-layer separator of Celgard2325 with a thickness of about 25 μm was used.

In order to prevent oxidation of the material, all operations are carried out in a glove box filled with argon.

Of course, not only to prevent oxidation of the material, but also to prevent the LiPF6 component in the electrolyte from reacting with water in the air to form hydrofluoric acid.

Hydrofluoric acid is something that anyone who has studied chemistry in high school knows.

And how dangerous this thing is, people who have been in silicon-based microelectronics laboratories should also know very well. Whichever hand is wiped a little, this hand is basically impossible to see people.

Judging from Senior Brother Qian's operation process, it is obviously more professional than Lu Zhou, a theorist.

Soon, the prototype was ready.

In order to prevent the sample from being destroyed, an edge-to-edge assembly method is used. Brother Qian completely covered the LiFePO4 material with a layer of diaphragm in the glove box, and carefully left a distance of 2mm between the free ends of the positive and negative electrodes.

This step is critical and is related to the safety of the experiment.

Taking out the sample from the glove box, Senior Brother Qian closed the air valves and let out a sigh of relief.

"That's it."

Looking at the sample in Senior Brother Qian's hand, Lu Zhou asked, "This is a battery?" ”

"A simple and unsafe lithium-ion battery," Qian said succinctly.

Lu Zhou was nervous for a moment: "Will it explode?" ”

Senior Brother Qian shook his head: "It won't explode, but if it is not operated properly, it may lead to a fire." ”

Moreover, it was a fire on a digital microscope.

Burning the sample is a trivial matter, but roasting the lens of a digital microscope is a big problem.

Lu Zhou estimated that this was also one of the reasons why Senior Brother Qian didn't let himself, a novice, touch the experiment.

The sample was connected to the BK-6808 rechargeable battery tester, and then placed on the digital microscope, Brother Qian set a few parameters to the computer, and repeated the steps on the paper in a low voice as if talking to himself: "Collect an image once in 2min, the data collection frequency is 1Hz, and the battery is charged for 400min for the first time and then discharged to the cut-off voltage...... OK. ”

The rest is a long wait.

Looking at the unchanged instrument, Lu Zhou couldn't help but ask, "Do you have to wait so long to do battery material tests?" ”

Four hundred minutes, that's almost seven hours.

Senior Brother Qian pushed his glasses and said: "Seven hours is the basic operation, sometimes you have to wait a few days to see the results, under normal circumstances, someone will be left on duty in the laboratory, basically Liu Bo and I take turns to do it." ”

"That's right," Liu Bo said with a smile, "I watched more than 40 dramas last year, and I watched them when I was on duty in the laboratory, do you want me to recommend some to you?" ”

Lu Zhou: "This, it's better not to use it." ”

Even if he did, he probably didn't have much time to read it.

After all the operations that needed to be done were done, Senior Brother Qian simply taught Lu Zhou some ways to deal with emergencies.

For example, if you see a sample coming out of smoke and smell something wrong, how to clean up the damaged sample, how to protect the instrument, and most importantly, how to protect yourself.

No matter how valuable an instrument is, it is not as important as a person.

Of course, this experiment was not so dangerous, so Senior Brother Qian threw the key into Lu Zhou's hand with confidence.

He and Senior Brother Liu still have some things, it is impossible to stay here all the time, and Lu Zhou is embarrassed to trouble people so much. After all, doing this experiment has already delayed them a lot of time.

Taking out the book on quantum chromodynamics, Lu Zhou sat next to the digital microscope, making up for his knowledge of theoretical physics, and glancing at the situation on the digital microscope from time to time.

Later, he realized that he didn't need to be so careful, and after being under the microscope for so long, it didn't look like anything had changed from the outside.

It can be seen that Senior Brother Qian's experimental skills are quite reliable.

Starting from more than ten o'clock in the morning, he stayed in the laboratory until almost six o'clock in the evening, during which Lu Zhou also ordered a takeout and had lunch.

Finally, when the set time was up, the charging and discharging were over, Lu Zhou kept the open circuit and waited for 10 minutes according to what Senior Brother Qian said, and then cut off the power supply.

Almost as soon as he had finished the finishing work, there was a sound of footsteps outside the laboratory, and Senior Brother Liu, who had just had dinner in the cafeteria, almost stepped on the laboratory.

"Done?" After glancing at the sample, Senior Brother Liu skillfully operated the computer and clicked the print button, "Then collect the data." ”

The printer buzzed.

Soon, Lu Zhou got what he wanted.

A set of pictures that record the growth of lithium dendrites under the microscopic level, as well as graphs such as cyclic voltage curves that the system requires to be collected, and so on.

While collecting these data, Senior Brother Liu said in a casual tone.

“…… Lithium is the most ideal anode material, but it is also the most difficult to serve. When charging, the lithium ions that return to the negative electrode will never turn back to a flat layer of lithium metal as you would like, but will bloom like a beautiful and deadly branch. ”

Waiting for the printer to finish printing the charts, Lu Zhou casually asked, "Fatal?" ”

"Yes, once this thing called dendrite is formed, it will continue to grow irrepressibly with continuous charging, and eventually it will be like a fork, piercing the diaphragm and touching the positive electrode."

Speaking of this, Senior Brother Liu paused and said in a joking tone: "Imagine what it would be like if you used a wire along with the positive and negative electrodes of the battery? That's right, it's a short circuit. And organic electrolytes are flammable, have you ever heard of Moli? ”

"No...... What's wrong? ”

Senior Brother Liu shrugged his shoulders and handed the printed A4 paper to Lu Zhou, "Their product almost made history, but because of the use of lithium as the anode, a major safety accident occurred, which led to the recall of NTT mobile phones, and finally the company went bankrupt and was acquired." In contrast, Sony is very smart, directly using graphite as the anode, and launched lithium-ion batteries to quickly occupy the market. ”

Lu Zhou couldn't help but ask: "Didn't they do a safety test?" ”

Senior Brother Liu sighed: "Yes, everyone will ask that, but things may be far from that simple. Maybe you didn't find a problem at all? Maybe they think they've found the perfect solution? Who knows? Sometimes, reality is just so magical. ”