Analysis of the technical route of solid battery

The pursuit of zero carbon trucks in the world's advanced countries is getting hotter and hotter, and the demand for new energy vehicle specifications has become increasingly clear. However, the sluggish development of lithium battery technology today has clamped down on cruising range and safety, making the upgrade of new energy vehicles slow down. The national standard (specific energy 300Wh/kg@2020) is approaching, the liquid lithium battery energy is limited by the innate safety problem (260Wh/kg has proved unable to control safety) and is unable to climb again, not to mention 350Wh/kg in 2025.

The long-term goal is hard to come by. Recently, the battery fire accident of the new energy vehicle has been happening again and again, forcing international automakers such as BMW and Toyota to start their operations. Whether it is investment, joint venture or joint development, it is only for the first step and the battery technology. A piece of paradise "solid-state battery" is strategically bundled.

However, the industry leaders have invested in solid-state batteries for about 20 years, but they are still in an unclear state. The battery factories have different electrolyte systems, and there is no technical flow or integration. Some of them have success. Production, some continue to postpone the development of the broad spectrum, throwing hundreds of millions of dollars and then leaving the scene is even more familiar, heaven and hell-like drop is caused by the difference in the essential route between the various electrolyte systems, instability, electricity Sexual performance and mass production have congenital advantages and disadvantages that are irreversible with modern science and technology. We divide electrolytes into six categories according to process and chemical system: oxides, sulfides, cyanide, halogen, films, polymers, etc. The four major technical routes illustrate the current status of their development:

Solid polymer

Thanks to the maturity of liquid polymer development, the mass production capacity of solid polymer batteries has not been far from liquid polymers, but there is poor stability resulting in poor electrical reliability, coupled with ion conductivity at room temperature. Poor battery performance is therefore greatly compromised, even resulting in a situation where it is difficult to operate below 10-4 S/cm.

Earlier, the French Bolloré Group used the BatScap battery to launch the car in the city network, but it must continue to heat the battery of the electric car to above 60 °C to maintain the conductivity inside the battery. The German component giant Bosch Bosch Group also had to abandon its investment in Seeo in early 2018; the most recent high-profile polymer electrolyte manufacturer Ionic Materials has received investment from Samsung SDI, Dyson, Wanxiang and other groups, perhaps In recent years, samples have been available.

Oxide film

Thin film batteries up to the micron level, once considered the best solution for the medical and wearable market, but similar to the semiconductor sputter production process, equipment costs, high environmental requirements, low yield, so mass production is not easy And the cost is very high.

The US IPS made an all-solid-state thin-film battery in 2008 and was acquired by Apple in 2014. So far, no products have been released. In addition, Dyson Dyson Group invested in Sakti3, which is the hottest news in the solid-state battery market in 2015, but in 2017. Announced the abandonment of all Sakti3 patents and turned to invest in solid polymer plants seeking to quickly enter the market. From this point of view, the commercialization of mass production of thin film batteries remains to be seen.

Sulfide

Although the conductivity is good, the stability is not the best, the shortest board, the stability of oxidation and reduction is also low, the process technology is complicated, and it is far from the lithium battery process. Therefore, the sulfide system has extremely high resources.

Toyota, Samsung SDI, and CATL have invested in the development of this system. Toyota expects its developed solid-state sulphide battery to be put into commercial use in 2022. South Korean battery manufacturer SDI turned to the beginning of this year after spending more than a decade on the sulphide technology route. The solid polymer route, the sulphide road is unreasonable, can only be proved by time.

Oxide

Oxide has the highest stability and can be produced in relatively inexpensive process equipment and factory facilities under normal atmospheric conditions.

Sony, Ohara and Huineng Technology are the representatives of this technical route. Among them, Huineng Technology has taken the lead in overcoming the oxides. It is the first to overcome the oxides. Its conductivity is poor, the oxidized metal stack is brittle and the bending will break. Such problems have successfully achieved the commercialization of "12-minute fast charge" and "dynamically bendable" solid-state batteries, and have been applied to HTC, Soft Bank and other brand products. Currently, solid-state power has been deployed with several car manufacturers in China, Europe, and Japan. Battery market.

In conclusion:

At present, the mastery of solid-state batteries is not high, and the willingness to share them is less. Therefore, the choice of the technical route of the battery factory is like an adventure that cannot be turned back. Each road has different obstacles to be overcome, before departure. I only know the advantages and disadvantages of the theory, but after seeing it all the way, it will be a dead end, a living road or a long and bumpy long road, but no one knows. We can only speculate from the trend of the industry that the current fastest oxide system, followed by solid polymer, should be able to come out in recent years; whether sulfide and thin film batteries are feasible in commercialization, at least 5 In the year, the oxide system has now officially entered commercial mass production.

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