Endurance 1000km, when will such an electric car be available?

When will there be an electric car with a battery life of 1000km? I have to start with this netizen's message:

The ability of netizens to dig holes is really strong, and a wave of their hands is a grand theme. In view of the unrealistic accurate description, Diange will briefly sort out the development process of mainstream power batteries in the order of time axis; Although you can't see the whole picture, it's also excellent to see the leopard in the tube ~

In the enlightenment era before 1980, electric vehicles were born before fuel vehicles.

In order to simplify the content and highlight the key points, Dian Ge called 1980 years ago the Enlightenment Age.

There is a famous cold knowledge that the birth of electric vehicles is much earlier than that of fuel vehicles. In the early days of its birth, pure electric vehicles were the absolute mainstream. After all, the earliest concept of electric vehicle can be traced back to the motor "toy" invented by Yedrick in 1828, but this invention has no clear concept of "power battery", so it is not a real pure electric vehicle.

In the following years, the first DC motor-driven electric car, the first electrically driven carriage and other aquatic products were born, but the common problem of these products is that they can not charge batteries, which can basically be regarded as disposable toys. Tell a joke, the purpose of inventing pure electric cars at that time was because the cost of carriages was too high for ordinary people to afford.

The turning point occurred in 1859, when gaston invented the lead-acid battery, which can be regarded as a serious power battery. On the basis of this invention, the first lead-acid battery electric vehicle was successfully born in 188 1 (even taking this as a reference, it was earlier than the first fuel vehicle in 1886). Then Camille improved the design intensively and made this lead-acid battery tricycle, with a weight of only 160kg and a top speed of12 km/h. Maybe you are not strong enough to run fast, which is much slower than a horse-drawn cart. In that era of great development of energy forms, electric vehicles, internal combustion engines and steam engines were three pillars.

Just like today, electric vehicles in the late19th century were quieter than fuel vehicles, and even the reliability of electric vehicles at that time was much higher than that of fuel vehicles, but it was limited by the capacity of lead-acid batteries carried by electric vehicles at that time. The endurance of these big guys is generally limited to 70 kilometers, and the top speed is only 30 kilometers per hour.

Let's summarize the characteristics. At this time, the power battery was large in size, large in mass and extremely low in energy density. It was exaggerated that the battery stack could not improve the battery life at that time, because after the battery stack was seven or eight hundred kilograms, the motor at that time could not even drive such a huge body. Even if new technologies such as nickel-cadmium batteries appear one after another in the same period, it is difficult to improve the essential dilemma. After entering the 20th century, it was an era of blowout of internal combustion engines, and the development of electric vehicles came to a stage of stagnation.

19 13 Ford model t production line, there is no tram during this time.

1976-1985 with the first oil crisis and the increasingly serious environmental problems, how to save energy and reduce emissions of automobiles has returned to people's field of vision. Naturally, we think of electric cars again. Among them, Stanley, John and Yoshino successively laid the framework of lithium-ion batteries. With the birth of lithium batteries, high-voltage rechargeable batteries have gradually entered people's lives. Since then, the human power battery technology tree has basically made a fuss about lithium batteries.

To commemorate their contribution to the world, the winners of the 20 19 Nobel Prize in Chemistry are these three buddies.

1980-2000 entered the lithium age: batteries such as lithium cobaltate and lithium ferrous phosphate appeared.

After entering the lithium battery era, what form to use as a vehicle-mounted power battery is not a one-off event, but a difficult exploration. Therefore, the first batch of truly pure electric vehicles we saw in the early days are still using some older battery technologies. For example, if you use the oil-to-electricity sign of nickel-chromium battery 106, the top speed is 90km/h, and the battery life is only 100km.

1995 logo 106 electric version, which looks like our old man's music.

There is also the well-known GM EV 1. Unlike the logo 106, the GM EV 1 is an original design that is absolutely pure electric. The two-seater coupe was very popular as soon as it was launched. The battery capacity of the early lead-acid battery version is 16.5kWh~ 18.7kWh, and the battery life of EPA is 65438+. The ups and downs of GM EV 1 are another story. If you are interested, you can watch the 2006 documentary who killed the electric car.

Last generation general EV 1

At this point, pure electric vehicles have gone through the road of eliminating lead-acid batteries and trying safer nickel-hydrogen batteries. However, Ni-MH battery is facing the dilemma of extremely low energy density, and the weight energy density basically stagnates below 80Wh/kg. If we want to launch a pure electric vehicle with long battery life, the Ni-MH battery is not ideal. It was not until Yoshinoya proposed LCO lithium cobalt oxide battery that lithium ion battery entered a period of vigorous development.

During this period, lithium batteries represented by LCO lithium cobaltate and LCO lithium manganate have made positive development, but it seems that it is always difficult to develop a set of mature vehicle-mounted power batteries. In the past, lithium cobaltate batteries had high energy density, but from the name, the cost was terrible, and it was not so realistic to build a huge automobile-grade battery. In the latter case, the cost of lithium manganate is reduced, but the service life is low and the energy density is reduced again. The result of this round of attempts is always unsatisfactory. Fortunately, lithium-ion batteries with large capacity and better cycle performance have been recognized as the development direction of vehicle-mounted power batteries.

Partial crystal model of lithium cobaltate.

This connecting flight took place at 1997. After unremitting efforts, John developed LFP lithium iron phosphate battery. Finally, he found a lithium battery technology that combines safety, low cost and high cycle life, making the commercialization of power lithium batteries possible.

The Great Leap Forward of Energy Density from 2000 to 2020: Debate on Lithium Ferrophosphate/Lithium Ternary

Everyone is familiar with the story after entering the new century, which is basically a situation in which lithium iron phosphate batteries and ternary lithium batteries compete with each other.

Lithium iron phosphate battery (LFP) is a lithium-ion battery with lithium ferrous phosphate as cathode material, and ternary lithium battery is a lithium battery with nickel cobalt as cathode material and manganese salt or aluminum salt to stabilize its chemical structure, mainly including NCM (nickel cobalt manganese) and NCA (nickel cobalt aluminum). Due to its chemical characteristics, lithium iron phosphate battery has a low voltage platform and an energy density of about 140Wh/kg. The ternary lithium battery has a high voltage and an energy density of 240Wh/kg. That is to say, under the same battery weight, the energy density of lithium ternary is easier to make higher than that of lithium ferrous phosphate.

Both NCM (Nickel Cobalt Manganese) battery and NCA (Nickel Cobalt Aluminum) battery have advantages over lithium iron phosphate battery in energy density, and the energy density continues to change subtly with the different ternary ratios. Specifically, according to the different proportions of nickel, cobalt and manganese or nickel, cobalt and aluminum, higher energy density is obtained. The principle is not complicated, that is, increase the proportion of nickel as much as possible.

Take NCM (Nickel Cobalt Manganese) battery as an example. According to their different contents, NCM523, NCM622 and NCM8 1 1 (numbers represent the proportion of nickel, cobalt and manganese) are common. There are some new energy sources such as Aion at present? S, Weilai ES6 and other models use NCM8 1 1 battery, and the energy density of the battery can be significantly improved under the premise of keeping the volume unchanged.

Guangzhou Automobile New Energy Aion? S

Weilai ES6

It can be seen that high nickel ternary lithium battery has become an inevitable development direction to improve capacity density in a short time. With the increase of nickel content, the specific capacity of ternary cathode material will gradually increase, and the energy density of the battery will also increase. For example, Tesla uses 2 1700 extensively? The energy density of NCA ternary lithium battery cell is as high as 260Wh/kg, and its nickel-cobalt-aluminum ratio is 8: 1.5:0.5. Undoubtedly, it belongs to "high nickel battery".

Generally speaking, lithium iron phosphate battery has low cost, strong cycle performance and strong safety, that is, its weight and energy density are relatively low; The Ni-Co-Al/Ni-Co-Mn ternary lithium battery has higher cost, stronger cycle performance and easier to improve the energy density of the system, but its stability is uncertain (especially for high nickel batteries). Therefore, in traditional cognition, ternary lithium batteries are more used in small passenger cars and lithium iron phosphate batteries are more used in large commercial vehicles.

It is worth noting that with the rapid development of high-nickel ternary lithium battery, its security risks also broke out in many security incidents on 20 19, which made people re-examine the pursuit of high energy density and long battery life, while safety can not be ignored.

2020-2025: With the continuous improvement of ternary lithium batteries, lithium ferrous phosphate may emit light in the second spring.

Judging from the current technical level, ternary lithium batteries will maintain the dominant position in the market, even for a long time. The energy density in the field of power batteries is expected to jump from the current 255Wh/kg to 300Wh/kg, and the endurance will be further improved from the current maximum of about 600km.

How to improve? There are several methods, which we are used to dividing according to the different packaging techniques and forms. At present, the mainstream can be divided into three types, namely cylindrical lithium-ion batteries, flexible lithium-ion batteries and square lithium-ion batteries. Since the commercialization of lithium-ion batteries, cylindrical lithium-ion batteries have been widely used in 3C and consumer electronic products. Tesla adopted Panasonic's 18650 and 2 1700? NCA cylindrical lithium-ion battery is characterized by mature winding process and high energy density, but the difficulty of electronic control increases accordingly.

Flexible packaging lithium-ion battery industry has developed for more than 20 years. LG, SK, AESC and other companies have a large number of mature products widely used. Its most obvious feature is that the shell is aluminum-plastic film, so the assembly process is relatively simple, and the lamination process is used in the field of power batteries. The corresponding square lithium-ion battery will understand that the manufacturing process is similar to that of the soft bag, only because the aluminum case and the cover plate are packaged by laser welding after assembly, and the liquid injection hole is left for secondary liquid injection after welding, so the assembly process is naturally more complicated. At present, winding molding process is mostly used.

Square lithium-ion battery (VDA size is mostly used in domestic vehicles) has the dual advantages of relatively low difficulty in electronic control and more prominent safety in manufacturing process, so it can be said that it has become an increasingly mainstream choice. At present, most of the breakthroughs of ternary lithium batteries are based on their existing lamination technology, thus breaking through the biggest problem of square lamination? -? The production efficiency that brings a lot of benefits may be the mainstream development direction of power batteries in the next few years.

Whether it is a soft bag or a square aluminum shell power battery, its height is generally limited by the design of new energy vehicle battery pack, and its shape is also developing in a longer direction. In order to comply with this trend, the traditional winding process battery can no longer meet the shape requirements of automobile-grade power batteries, and will be replaced by batteries produced by lamination process. It is precisely because of the flexible size of the laminated battery core and not limited by the winding needle structure that the laminated production has high interface flatness of the pole piece.

The flatness is higher, and the most direct change is that the energy density will be increased by 5%, the cycle life will be increased by 10%, and the cost can be reduced by 5% after the technology is mature and large-scale. On the premise of not changing other processes and raw materials, the cycle life of 10% can be improved only by using lamination process.

Therefore, in the future, power batteries will gradually abandon modularity and develop towards specialization (vehicle regulations) and scale. The larger the volume, the more prominent the advantages of lamination, which is also the development trend of power batteries in the future. Industry giants such as Panasonic, Samsung SDI, CATL, BYD and Honeycomb all plan to introduce laminating technology in the near future.

Of course, in addition to the process, ternary lithium batteries will also make a lot of efforts in reducing cobalt (reducing costs) and exploring new materials. The purpose and process improvement are similar, so I won't go into details here.

In addition, it is worth noting that the process of lithium iron phosphate battery has been greatly improved, and the energy density of its battery system has reached about 160Wh/kg. Although there is still a gap compared with the current high-nickel battery, this performance is obviously enough for large commercial vehicles and some passenger cars with less extreme endurance requirements. Coupled with the advantages of cost and safety, lithium iron phosphate battery is expected to glow in the second spring and increase the installed capacity again.

2025: Solid-state batteries are on the rise.

Unfortunately, by upgrading the process and changing the ternary ratio upgrading process to improve the performance of lithium batteries, the growth space is bound to be limited, and at the same time, it has to bear the cost of more active chemical characteristics. Is there a longer-term and more promising battery technology? Of course there is. This is the ultimate goal of vehicle-mounted power battery, solid-state battery.

Because of the inherent advantages of solid-state batteries in chemical characteristics, the energy density will easily exceed 400Wh/kg, the impact life will be 1000km, and the safety will also make a qualitative leap.

Solid-state lithium batteries, as the name implies, use solid electrolyte instead of diaphragm and electrolyte. Solid-state battery is revolutionary for improving the performance of vehicle-mounted power battery; Figuratively speaking, compared with traditional lithium batteries, the performance improvement of solid-state batteries using solid electrolyte on mechanical hard disks is comparable to that of solid-state hard disks.

There are too many benefits brought by solid electrolyte. The first thing to bear is to directly use metal lithium as the negative electrode, without the graphite negative electrode of the traditional ternary lithium battery. Only in this step can the energy density be greatly improved. Secondly, solid electrolyte also allows the use of cathode materials with larger capacity, and can also be superimposed to improve energy density, with more obvious benefits.

More importantly, solid electrolyte has many core advantages, such as non-flammable, non-corrosive, non-liquid leakage and non-volatilization. In the past, the safety problems that pure electric vehicles were worried about will be solved.

It solves the problems of battery life and safety, not to mention that solid-state batteries have many advantages such as small size, long life and easy recovery. Therefore, in the foreseeable future, solid-state batteries will be the development direction of vehicle power batteries and even the whole battery industry.

Even though the research and development is difficult and costly, the future of solid-state batteries is still clear under the demand of the whole industry. By then, I'm afraid that the battery life of electric vehicles running all over the street will exceed 1000km.

This article comes from car home, the author of the car manufacturer, and does not represent car home's position.