Technology overlord starts with new energy vehicles

Just when some domestic brands that originally made cars gradually entered the field of Laotou Le manufacturing.

Nishikawa Province, Kyushu Automobile Works.

After more than two months, today's Kyushu Automobile Factory has undergone tremendous changes.

Next to the old factory of the original Kyushu Automobile Factory, two newly established factories have been completed.

Compared with the previous Kyushu Automobile Factory, the scale is even worse.

One of the factories is the Jiuzhou Electric Vehicle Factory, which produces two-wheeled electric vehicles.

The other factory is Hengxin Battery Factory, which specializes in providing batteries for Kyushu Mini and the next Kyushu two-wheeled electric vehicles.

At this time, inside the Hengxin Battery Factory.

The high-level managers of Kyushu Automobile, under the leadership of Xu Yifan, are inspecting this battery production line that has just officially started production today.

It is different from the Kyushu Automobile production workshop where you can easily see pieces of material being processed and turned into auto parts.

There are more devices here, but you can no longer witness the process of turning a piece of material into a battery.

Lithium-ion batteries are a complex system, including positive electrodes, negative electrodes, separators, electrolytes, current collectors, binders, conductive agents, etc.

The reactions involved include electrochemical reactions of positive and negative electrodes, lithium ion conduction and electron conduction, and heat diffusion.

The production process of lithium batteries is relatively long, involving more than 50 processes in the production process.

On the whole, the lithium battery manufacturing process can be divided into front-end process (electrode manufacturing), middle-end process (cell synthesis), and back-end process (chemical formation and packaging).

The production goal of the front-end process is to complete the manufacture of positive and negative electrodes. The main processes are: mixing, coating, rolling, slitting, sheeting, and die-cutting.

The equipment involved mainly includes: mixer, coating machine, roller press, slitting machine, sheeting machine, die-cutting machine, etc.

In the first process of the battery production workshop, the incoming materials are inspected by the staff and transported to the next process according to the positive and negative materials.

After the crushed phosphate rock and iron ore have been tested, they are transported by the conveyor belt to the batching process for the next stage of processing.

At the same time, Lu Jingping, who followed Xu Yifan and others, introduced information related to these devices.

"Lithium iron phosphate molecular formula LiFePO4, also known as lithium iron phosphate, lithium iron phosphorus, or LFP for short, is a positive electrode material for lithium-ion batteries.

There are many methods for preparing LiFePO4 cathode materials, which can be roughly divided into liquid-phase method and solid-phase method.

The liquid-phase method includes co-precipitation method, hydrothermal method, sol-gel method and other low-temperature synthesis methods.

Solid-phase methods include high-temperature solid-phase sintering, carbothermal reduction, and microwave sintering.

And our Hengxin Battery Factory uses a high-temperature solid-phase method.

The preparation method of this positive electrode material has the advantages of simple process, easy industrialization, easy removal of decomposition products to reduce impurities, easy control of preparation conditions, and the like.

The disadvantages are that the crystal size of the produced positive electrode material is large, the phase is uneven, and the calcination time is long at the same time. "

Under the leadership of Cui Wuyuan, who is responsible for managing battery production tasks, and Lu Jingping, who is in charge of technical support and built the battery factory, the people wearing dustproof clothing walked slowly in the battery production workshop.

Cui Wuyuan, a Samsung talent, also has considerable management ability. He was able to stand out among hundreds of workers in just a month or so, which shows his outstanding learning ability. After he was promoted from skilled workers by Xu Yifan, he was temporarily in charge of managing the battery production workshop Production department deputy manager for production tasks.

Ingredients, positive electrode coating, negative electrode coating, positive electrode sheet production, negative electrode sheet production, positive electrode solder tab, negative electrode solder tab, cutting diaphragm, inspection and dust removal, core pressing, short circuit detection, bottom and top coating, shell entry, short circuit detection again, Cover plate welding, baking, injection of electrolyte, formation, volume separation, measurement of internal resistance and thickness, packaging, full inspection, and delivery.

A group of people walked through the long production line and saw many employees who were busy in production.

From time to time someone shouted for help.

"Qiu Gong, save me, save me!"

"Master Jiang, come quickly!"

Some steps that are not particularly proficient, and occasionally encounter situations that you don’t understand, you have to ask the original R\u0026D team responsible for the technology to be responsible for guidance!

Of course, there are still relatively few calls for support. It’s just that from training to practical operation, some small details that I haven’t noticed before are still uncertain, and I can get used to it in two days.

Cui Wuyuan reported the current working conditions of the employees in the battery production workshop.

"Nowadays, these employees are not particularly proficient in their work, and their production capacity has not reached its peak at all.

However, because the battery factory is large enough, it is estimated that this production workshop can already supply the Kyushu Mini of Kyushu Automobile.

At the same time, when the employees are skilled, the battery factory can meet the needs of Kyushu Mini and two-wheeled electric vehicles under full power operation.

In addition, this is only the first production workshop, and five battery production workshops of the same size are under construction in the later period. "

Although the managers are confused about the craftsmanship.

As for how many batteries can be produced, it is much clearer.

After leading everyone to check around, everyone finally saw the final finished battery.

In the last process of the product line, the batteries that have passed the test are packaged into battery packs with different capacities after the capacity measurement.

The casing of the battery pack is uniformly made of high-strength plastic.

According to the difference of capacity, the number of batteries packaged inside is different.

Some pack the battery to the brim, and some put some materials in the middle to make up the number.

The battery pack with uniform specifications, the packaged battery pack is similar to a large battery, and it is common on all the new Kyushu Mini, but the capacity is different. According to different configurations, it can be installed on different models, and it can be directly use.

Looking at the battery packs produced piece by piece, Lu Jingping said with a little regret.

"Unfortunately, due to factors such as cost and production process, this battery cannot fully achieve the performance of lithium iron phosphate batteries manufactured under laboratory conditions.

The performance of the final product is only about 80% of the samples prepared in the laboratory.

The energy density is 130Wh/kg, and the low-temperature environment capacity is only 60%. After more than 4200 cycles, the remaining battery capacity is 80%. "

Xu Yifan comforted and said: "Even if it is about 80%, the performance is enough now.

I believe that you will develop better and more powerful batteries in the future. At the same time, our manufacturing process will be improved in the future, and we will have more money to buy better equipment. "

After finishing speaking, he continued to ask: "By the way, what is the specific safety of this battery?"

Safety is Xu Yifan's top priority!

Although theoretically speaking, lithium iron phosphate batteries have basically no risk of fire, this new type of lithium iron phosphate battery is naturally safer than ternary lithium batteries.

But Xu Yifan still needs to ask about the actual product.

Lu Jingping didn't even want to answer: "We have optimized the safety of this battery according to your requirements, the boss!

The finished product has passed thermal shock, overcharge, short circuit, heavy object impact, overcharge protection, overdischarge protection, short circuit protection, constant damp heat performance, battery external stress.

Vibration, collision, free fall, external short circuit, forced discharge, abnormal charging, wrong installation, over discharge, low air pressure, extrusion, high rate charging.

Acupuncture, puncture, external electric shock, knife hacking, etc.

And all test results are excellent! "