In fact, mobile phone manufacturers have taken aim at this advantage of solid-state batteries. Since 2012, Apple has been actively deploying patents for all-solid-state battery technology, looking forward to using this new type of battery with high energy density, high safety, and flexibility potential in iPad, MacBook and other devices and flexible electronics to be developed in the future. On the device. In November 2015, the United States Patent and Trademark Office published a new Apple patent related to solid-state battery charging technology-solid-state battery charging technology for portable devices.
All-solid-state batteries can become the mainstream direction of battery development recognized by the battery research and industry circles in the next step, which is directly related to their unique performance.
High safety: The solid-state battery can separate the positive side of the air from the negative side of the lithium metal due to its solid electrolyte, which can completely prevent the direct reaction between atmospheric components and lithium metal, and the maximum operating temperature of the battery can be raised from the current 40°C to higher , So that the battery can adapt to a wider range of operating temperature, and the application range will be wider. Therefore, safety is one of the most fundamental driving forces for the development of all-solid-state batteries.
High energy density: After solid-state batteries replace the separators and electrolytes of traditional lithium-ion batteries with solid electrolyte materials, the applicable material system for lithium-ion batteries has also changed. Instead, metal lithium is directly used as the negative electrode, which can significantly reduce the amount of negative electrode material and significantly increase the energy density of the battery. The increase in energy density is conducive to making batteries more portable. One of the development directions of my country's new energy vehicles is lightweight. If solid-state batteries can be commercialized, they will contribute to this.
Flexibility prospects: Due to the lightness and thinness of solid-state batteries, it has the potential to be further optimized into flexible batteries. Flexible batteries developed from solid-state batteries can withstand hundreds to thousands of bends without degrading performance. This type of battery is the best power source choice for some wearable electronic devices. Apple's vigorous research and development of solid-state batteries is precisely because of its flexible prospects.
However, the advent of a product always has to go through various tests, and solid-state batteries are no exception. In an all-solid-state lithium-ion battery, the solid-solid contact between the electrode and the solid electrolyte has a higher interface contact resistance than the solid-liquid contact. At the same time, the interface compatibility and stability also significantly affect the performance of the all-solid-state lithium-ion battery. Cycle performance and rate performance. In addition, solid-state batteries are also facing development bottlenecks in which production processes need to be improved and costs need to be reduced.
In response to these problems, many scientific research institutions have done a lot of research and development work.
Sakti3, founded by former University of Michigan engineering professor Mary Setterley in the United States, has developed a solid-state lithium-ion battery using flat-panel TV and solar panel manufacturing technology. This battery uses "thin film deposition technology" to make The cost is only one-fifth of the current cost of lithium-ion batteries, but the energy density is twice that of lithium-ion batteries.
The R&D team of Qingdao Energy Storage Industry Technology Research Institute has developed a series of all-solid polymer electrolytes with excellent comprehensive performance. The electrochemical window of this new all-solid electrolyte membrane can be as high as 4.6V, and the thermal stability temperature of the electrolyte can reach at least 200°C. When this electrolyte is used in an all-solid-state lithium-ion battery, after 1000 long cycles of charge and discharge, it still maintains a capacity of 92%. At present, this high-energy-density, high-performance all-solid-state lithium-ion battery has passed the 11,000-meter full-sea depth simulation pressure chamber cycle pressure test, and it is expected to become the ideal energy power for all-sea deep submersibles such as "Jiaolong" in the future.
Researchers at the Swiss Federal Institute of Technology Zurich used garnet as an electrolyte to enlarge the contact area between the solid-state battery electrode and the electrolyte, thereby realizing the effect of accelerating the charging speed of the solid-state battery and being able to withstand a high temperature of 100°C.
The United States SunCultureSolar applies solid-state battery technology to the field of energy storage. It has developed a new integrated solar panel with a built-in solid-state low-voltage battery and seamless integration with the inverter. This fully integrated product design can reduce the total cost of solar installation and energy storage by more than 50%.
The solid-state battery does not contain flammable liquid electrolyte, which can greatly improve the safety of the battery, and it will surely become an advanced technology touted by the battery industry. Since the research and development of solid-state batteries in all countries in the world is in its infancy, it is now the best time for solid-state battery research, development, and industrialization. In addition, the accumulation of R&D technology and related experience for solid-state batteries is also vital to the future research and development of lithium-sulfur batteries and lithium-air batteries.