Will the prospect of Tesla's "Battery Day" set off a technological revolution?

SMM News: with Tesla's "Battery Day" approaching, more insider information flows out. Although Tesla is an electric vehicle brand, with its research and development accumulation in battery technology, its influence in the field of battery technology has been very important, and its technical direction has even been said as a weather vane in the industry. What's more, Tesla is still thinking of developing his own battery, so what artifact it will release on "Battery Day" will naturally attract the attention of the global battery industry.

Guess one: will the process structure start with a larger cell?

Recently, it has been revealed on overseas social media that Tesla's "new battery", also from the cylindrical battery family, is larger than the 21700 cylindrical cell mainly used by Tesla.

It is reported that Tesla also has an interesting name for this new type of battery-"cookie box (Biscuit Tin)". In addition, sources also revealed that the battery, which will be produced in Tesla Austin Super Factory, is a battery of Tesla's "Roadrunner" series. In the future, it will be used for CyberTruck pickups, Semi trucks, and possibly locally produced Model 3 and Model Y models.

If the revelations are true, then Tesla in the pursuit of energy density and cost reduction on the technology path, or even can be said to be a "routine", and last year's Ningde era, BYD in the battery process CTP and blade battery take a bit similar: starting from the process and structure, do large single cell size, improve the battery pack space utilization, reduce the number of parts in the battery package. Synthesize these process innovations to improve the carrying capacity of battery PACK and reduce the cost of battery PACK.

Many years ago, in order to improve the carrying capacity of electric vehicle batteries and reduce costs, Tesla did not meet the 18650 cells provided by Panasonic at that time, and took the lead in using 21700 cells on a large scale in the industry. This practice of "upgrading" through batteries quickly triggered imitation in the industry, and many domestic power battery companies began to layout 21700 cylindrical battery production lines.

So it seems that Tesla's evolution idea on the cylindrical cell is to work hard in the direction of large size.

It is reported that Tesla's new battery may carry more power. Foreign media quoted sources as saying that the diameter of the new battery is twice the diameter of the 21700 cell currently produced at the Gigafactory1 battery factory in Nevada, "which may mean that the unit volume of the new battery has increased more, closer to the size of the capacitor." Correspondingly, the energy density of the new battery is also expected to increase. At the same time, it is expected to achieve a significant reduction in battery PACK cost as a whole because of the reduction in the number of cell shells and structural components.

In addition, in photos posted on the Internet, the new battery appears to have a non-polar ear design, which Elon Musk called "much more important than it sounds" last year.

If the new battery is indeed inspired by the patent of Tesla electrodeless electrode, the composition of the new battery will pave the way for improving performance and further reducing production costs.

In fact, Tesla has been doing "subtraction" on the module side in recent years. At present, the number of Tesla Roadster and Model Splash X battery modules is 16, while the number of Model 3 battery modules is only 4. If Tesla launches a larger-sized cell on Battery Day, it will be worth looking forward to whether the module structure will continue to be simplified and whether there will be a CTP integration scheme similar to that being done by domestic enterprises.

Judging from the previous revelations in the industry, Tesla's changes in cell size and technology should be unexpected to the industry, but carefully comparing the trend of the technical route of domestic battery enterprises, we can see that innovative attempts have been made in this respect all the time, and related products have been loaded and applied.

However, if it is only the innovation of the process section, it is obviously not in line with Tesla's campaign behavior that has been "Battery Day" for the past six months. Tesla has consciously or unintentionally revealed to the outside world the progress of his battery technology, such as million-mile batteries, electrodeless electrode cells, silicon nanomaterial cells, cobalt-free batteries and other new technologies.

Guess 2: will the silicon nanowire battery be launched?

Improving battery energy density has always been one of the main directions of battery technology research and development, and the breakthrough of battery energy density improvement should start from the battery material end. In August this year, Tesla announced the invitation poster of the "Battery Day" event, which sparked speculation in the industry about his battery material technology breakthrough.

The lattice line pattern on the background image of this poster is considered to be the structure of silicon nanowires, a new battery material, which leads to new speculation: is Tesla going to launch silicon nanowire batteries?

According to industry insiders, silicon nanowires are a new type of semiconductor nanomaterials. "it solves the problem that ordinary silicon materials are easy to expand and crack, and at the same time can store ten times more electric energy than conventional battery anode material graphite." If its application creates a new type of battery, the energy density of the cell can be increased by 50%. "

In addition, a picture of Tesla's factory posted online shows Amprius, a patented technology company for silicon nanowire battery anode materials, located near Tesla's Fremont plant in California, where Tesla's upcoming Battery Day is located. This probably implies that Tesla and Amprius are already working together on silicon nanowire technology.

Tesla plans to achieve mass production of power batteries with energy density 400Wh/kg within three to four years. Silicon nanowires may become one of the important technical supports for achieving this goal. Tesla is looking forward to having relevant information about this technology on Battery Day.

Guess 3: millions of miles of battery will be unveiled?

The term "million-mile battery" was mentioned by Tesla last year. In April 2019, Musk said he wanted to develop a battery that could last up to 1 million miles (1.6 million kilometers) in its full life cycle.

In June of the same year, the team of Tesla battery expert Jeff Dayne (Jeff Dahn) published a paper in which it mentioned that Tesla's new battery will use a new generation of "single crystal" NCM523 materials and more advanced electrolytes. "compared with modern traditional batteries, its charging life cycle will be increased to 4000 times, and the car mileage during the battery life cycle will exceed 1 million miles."

It is worth mentioning that once Tesla's million-mile battery is mass produced, the service life of Tesla electric vehicle will be at least twice as long as it is now, which means that the whole life cycle cost of electric vehicle will be lower and the battery residual value will be higher.

After Tesla proposed the "million miles" battery, some domestic battery companies have also announced the research and development of their long cycle life batteries one after another, among which Ningde era and Honeycomb Energy have revealed their own company's research and development of millions of kilometers of battery technology.

With a range of up to one million miles, the value of the battery life cycle will be significantly extended, so the expectations of the industry are also very high. According to Tesla's campaign in the first half of this year, there is a good chance that the "million miles" battery will be unveiled.

Guess 4: is the cobalt-free battery a gimmick or a real one?

In view of the limited cobalt reserves and high cost, low-cobalt and cobalt-free battery technology has always been the direction of attention and efforts in the industry. Musk has also publicly stated many times that he wants to reduce the amount of cobalt in the battery, even to be completely cobalt-free. At the beginning of this year, the news of Tesla's "cobalt-free battery" reported by the media caused bloodshed in the capital market, and the stocks of listed companies involving cobalt and lithium iron phosphate batteries were "toyed with". However, due to the repeated postponement of its "Battery Day", the industry has not seen the specific research and development of its cobalt-free battery.

By contrast, domestic Honeycomb Energy took the lead in releasing two samples of cobalt-free battery products in May this year, and plans to officially launch them to the market in the second half of next year. In addition, Ningde Times also revealed that "the company has its own 'cobalt-free' battery technology reserves, research and development is progressing smoothly, is looking for ways to improve the supply chain."

It is worth noting that as the current exclusive supplier of Tesla power batteries in North America, the head of Panasonic's US electric vehicle battery business said that Panasonic plans to commercialize cobalt-free batteries within 2-3 years. Therefore, whether Tesla will announce his cobalt-free battery on Battery Day is also very noteworthy.

In people's impression, Musk is a person who plays cards according to common sense and has very subversive thoughts. Musk has personally described his "Battery Day" as there will be a lot of "exciting" content, I believe that the highlight of the "Battery Day" should be more than the relevant revelations from the industry. Of course, any of these battery technologies can be turned into reality as soon as possible and can be called "exciting" when applied to electric vehicles. What battery technology secret weapons Tesla has will be known tomorrow.