Recently, media reports reported that Fisker, an electric carmaker, has just applied for a patent on solid-state batteries. This patent raised the battery life of an electric vehicle to an alarming 804 km and reduced charging time to one minute.
In China, as one of the core components in the development of electric vehicles, power battery has been a hot research topic in the field of batteries.In the key state key research and development program of new energy vehicles started in 2016, Li, a researcher in the Clean Energy Laboratory of Institute of Physics, Chinese Academy of Sciences Wang is responsible for the 'long life force lithium battery new materials and new system research' project, aimed at developing high energy density, high safety lithium battery to improve electric vehicle mileage, the project proposed lithium-ion battery, semi-solid lithium-sulfur battery , Solid lithium-air battery three long-lasting power lithium battery, or will become the future of China's new energy vehicles core.
Challenge battery ultimate energy density
'To improve the energy density of power battery cells to 400Wh / kg or more, will help significantly improve the driving range of electric vehicles.Beiqi EV200, for example, 400Wh / kg batteries, equivalent to more than 800Wh / L volume energy density. A battery pack volume and per kilometer of electricity consumption constant, a charge can not only battery life of 620 km; also can reduce costs and extend the life of the current electric vehicle to solve the larger differences between the performance of the fuel truck. 'Recently, Lee Wang accepted science and technology daily reporter said in an interview.
As an important part of the overall R & D of new energy vehicles in China, the mission of this project is to develop new batteries with energy density of 400Wh / kg or more at the forefront of the industrial chain, and to recognize and key the key basic scientific problems of accumulating high energy density batteries Technology, and for enterprises to simultaneously develop 300Wh / kg batteries provide an important reference and guidance.
'Long-life lithium-ion battery new materials and new system research' R & D team is in the project to assume the task of challenging the battery ultimate energy density.
Production of batteries energy density 300Wh / kg can be achieved
Reporters from the enterprise declared a public R & D program found that for the 300Wh / kg lithium-ion battery routes, the project team chose a high-nickel positive and nano-silicon carbon anode.
'According to the recent progress, the technical indicator that the energy density of a production cell reaches 300Wh / kg can be realized,' said Li Hong.
In recent battery research on new systems, the lithium-rich material used in the R & D team of Research on New Materials and Systems for Long-life Lithium Batteries has a positive electrode energy density of 348Wh / kg and a cell density of The lithium-rich material is a positive electrode, and the specific energy of the lithium-ion battery is 573Wh / kg; the specific energy of the lithium-sulfur battery reaches 600Wh / kg; the specific energy of a lithium-ion battery reaches 780Wh / kg.
"The development of high-energy-density batteries in excess of 300 Wh / kg, with lithium metal as an anode, is an important common technology. Some research groups have proposed the use of solid electrolytes or mixed solid-liquid electrolytes to address the major challenges facing batteries that use or contain metallic lithium negative electrodes Technical challenge. "Li Hong said.
The Chinese Academy of Sciences (CAS) laid out the Strategic Leadership Class A project of the Chinese Academy of Sciences in November 2013. The project also supported the development of solid-state batteries. Three of the teams made progress in polymer, sulfide and in situ solid-state technologies.
The technology is clear but still faces challenges
At present, the soft electrolyte batteries for developing and producing liquid electrolyte lithium-ion batteries generally comprise 15% -25% by weight of liquid electrolyte and negative carbon, silicon, etc. In the long run, all-solid-state lithium metal batteries need to be developed in the future, Contains lithium metal, the battery does not contain any liquid. "Li Hong said.
Li Hong said that from the development of mixed solid-liquid electrolyte batteries and all-solid-state lithium-ion battery industry, the need to focus on the development of solid electrolyte and lithium metal materials to address the interface ions and electronics Transmission, and volumetric deformation, thermal stability problems.Most of manufacturing equipment can be achieved through the use of existing lithium-ion batteries and primary lithium-ion battery manufacturing equipment.
In addition, production environment control technologies such as drying rooms for large-scale production of lithium metal batteries have also been mastered.Although many challenges in science and technology are faced with the development of mixed solid-liquid electrolyte batteries and all-solid-state lithium metal batteries, challenges in controlling costs are also included .
'As long as we thoroughly study and thoroughly understand the basic science issues and put forward feasible and creative comprehensive solutions, we hope that there will be even difficulties,' said Li Hong.
