At the current stage, the power battery is aimed at increasing the energy density and reducing the cost. The focus of the solid-state battery introduction is on the weight reduction of the vehicle body.
From the perspective of the battery structure, the structure of a conventional liquid lithium-ion battery is a positive electrode, a negative electrode, an electrolyte, a separator, and a structural case; among them, the separator and the electrolyte account for approximately 40% of the total weight of the battery, and the volume is approximately 30%. .
The solid-state battery changes the electrolyte in the solid electrolyte to conduct the conduction of the charged ions. In contrast, it eliminates the electrolyte, the separator, and the like, so that the volume is smaller, the density is higher, and the battery construction steps can also be improved. Simplify; At the same time, due to the lack of electrolyte, it also removes the battery leakage, electrolyte evaporation or burning at high temperatures and other issues, help improve battery safety and service life.
From the aspect of electric vehicles, lithium-ion batteries used at this stage are mainly made of lithium iron phosphate (LFP), nickel manganese cobalt (NMC), lithium manganese oxide (LMO) and other ternary materials. The choices are not the same.
Since 2017, cobalt metal prices have continued to rise, coupled with the demand of electric vehicles for increased battery energy density, which led the battery factory to introduce high-nickel NMCs with lower cobalt content, thereby increasing the nickel's weight to increase the cell's capacity. Since the proportion of cobalt is reduced, the cost of the core is reduced, so the high-nickel NMC is an important development direction of the electric vehicle battery in 2018, including the Nissan Leaf E-Plus, Hyundai Kona EV, and Volkswagen ID 2019 models, all planned to use NMC. The ratio is 8: 1: 1 high nickel NMC battery.
Even though the introduction of high-nickel NMC batteries is expected to solve the challenges of cost and battery energy density, due to the limitation of the inherent vehicle conditions of the internal combustion engine model, it is possible to reduce the battery volume and reduce the weight without degrading the energy density. Direction with battery plant effort.
The solid-state battery has the advantages of small size and high density, and it has become an important consideration for vehicle manufacturers to develop lighter body weight. At the same time, the solid-state battery has better thermal stability, and is expected to reduce the carrying capacity of the heat sink and further promote lighter weight.
On the other hand, solid-state batteries represented by glass or ceramic electrolytic electrodes at the present stage have a wider electrochemical window and therefore have better compatibility with high-voltage positive electrode materials, which also meets the development trend of high-nickel NMC at this stage. .
As the depots focus on increasing the battery capacity density and driving the increase in endurance, the next step is expected to achieve lighter weight through the introduction of solid-state batteries.
The depot, battery plant has been deployed, solid-state battery electric vehicles are expected to be available within 3 years
Solid-state batteries in the production process, process methods and lithium-ion batteries are different, so now the major depot major strategic investment, alliance mode for the solid-state battery layout, in addition to Renault-Nissan Alliance, including BMW alliance start-up company Solid Power and investment Ionic Materials, planning to launch electric vehicles using solid-state batteries in 2026; Toyota is working with Ilika Technologies to develop solid-state batteries for automobiles, and plans to launch solid-state battery electric vehicles in 2022.
Dyson, which has announced its entry into the electric vehicle market, has also adopted the acquisition of Sakti 3, a solid-state battery technology company. China’s new vehicle company, Weima, has teamed up with Taiwan’s solid-state battery developer, Huineng Technology, and built a 5GWh solid state in 2018. The battery plant is expected to be completed and put into production in 2019; Hyundai will use its own research and development to layout solid-state batteries.
In addition to the depot, the battery factory began to actively deploy, including Panasonic EV Energy and Toyota have jointly invested in the development of solid-state batteries in the vehicle direction; Hitachi Vehicle Energy also announced the commercialization of solid-state batteries developed by 2020; GS YUASA in Japan is Joined with Bosch to acquire solid-state battery company Seeo; Chinese battery giant Ningde also began to accelerate the development of solid-state lithium-ion batteries for electric vehicles.
In fact, solid-state batteries have been used in electric cars. The French start-up company Autolib launched 3,500 electric shared cars using solid-state battery technology in London in 2015.
In the last two years, major car manufacturers began to announce the time-to-market for solid-state battery electric vehicles, and battery manufacturers have gradually invested in the construction of solid-state battery production lines. It is estimated that electric cars using solid-state batteries will be available in the market for three years.