Tesla Battery Day's latest spoiler: or launch a large battery with twice the diameter of the battery cell

What joy will Tesla’s battery day and shareholder meeting held on September 22 bring to the outside world? According to speculations by many industry organizations and foreign media, these joys may include cobalt-free high nickel batteries, silicon-nano-wire technology batteries, dry electrodes, and so on. According to the latest 'spoiler' of the American professional new energy vehicle website electrek, Tesla will show off a large cylindrical battery on Battery Day. 'Suspected' Tesla's newly developed large battery. Image source: electrekelectrek reported that, according to an anonymous source, the large battery is one of the results of Tesla's self-developed battery project Roadrunner. The core of this large battery is twice the diameter of the 2170 cylindrical battery currently used in Tesla Model 3 and Model Y. The specifications of the 2170 cylindrical battery are 21 mm in diameter and 70 mm in length. The 2170 cylindrical battery is processed by Gigafactory1, a joint venture between Panasonic and Tesla in Nevada, USA. The technical route is a ternary lithium battery with a positive electrode material polymer of nickel cobalt aluminum (NCA). According to electrek, the diameter is twice that of the 2170 cylindrical battery, which means that the cell volume of the large battery is four times that of the existing cells. If the battery can be fully utilized, the capacitance will be greatly increased, the number of batteries and assembly sets will be reduced, and the cost will be reduced. Electrek said that this large battery may use a new type of electrodeless battery unit that Tesla applied for in May of this year. Regarding this specially designed new type of electrodeless battery, Musk once said on Twitter, 'This is more important than it sounds.' The electrodeless battery unit is a new type of battery manufacturing method that can reduce the resistance of the existing path inside the battery cell and improve the battery performance. The energy density of the 2170 cylindrical battery is about 260Wh/kg. Tesla CEO Elon Musk recently stated that batch processing of batteries with a high cycle life of 400Wh/kg with a volume density of 400Wh/kg is not far away, and it may only take three to four years. Silicon nanowire battery technology is also one of the industry's expectations for Tesla Battery Day. An anonymous professor from the National Key New Materials Laboratory told the interface news reporter that silicon nanowires are different from the currently used ternary batteries and lithium iron phosphate batteries, and there is no alternative relationship. The key structure of lithium battery includes positive electrode, negative electrode and electrolyte. Lithium iron phosphate, lithium nickel cobalt manganate or lithium nickel cobalt aluminate are commonly used materials for the positive electrode of lithium batteries; graphite and silicon are commonly used as negative electrode materials. Silicon nanowire is a kind of semiconductor nanomaterial, the diameter of the wire body is generally about 10 nanometers, the inner crystal core is single crystal silicon, and the outer layer has a silicon dioxide coating layer. The aforementioned anonymous professor told the interface reporter that the advantage of silicon nanowire battery technology lies in its higher theoretical energy density. He also pointed out that the biggest problem with silicon nanowires is that after the material is nanosized, the energy density of the assembled finished battery is reduced, and the specific surface area of u200bu200bthe nanomaterial is large, the reaction activity is large, and the side reaction with the electrolyte will increase. 'The side reaction refers to the irreversible reaction between the negative electrode of the battery and the electrolyte, resulting in a loss of capacity.' The professor said. He believes that it will not take too long for the silicon nanowire battery technology to go from research and development to commercial use, because the silicon carbon anode has already been used. Whether Tesla will show off its silicon nanowire battery technology can only be announced on the battery day four days later. Disclaimer: Some pictures and content of articles published on this site are from the Internet, please contact to delete if there is any infringement.