Shandong Good Achievement | Combining high safety and long cycle characteristics, Shandong has achieved independent breakthroughs in all solid state lithium battery technology
How can a battery achieve high energy density, long lifespan, and intrinsic safety simultaneously? The high specific energy and long-life all solid state lithium battery developed by the Chinese Academy of Sciences Qingdao Institute of Bioenergy and Process (Shandong Energy Research Institute) has made a major breakthrough: it not only achieved the "slimming" of cathode materials, but also retained 80% of the initial capacity after the energy density reached 390Wh/kg and 5000 cycles, and greatly improved the safety of the battery. This achievement is expected to drive an energy revolution in fields such as new energy vehicles, deep-sea equipment, and low altitude aircraft.
All solid state lithium battery
The positive electrode material has undergone significant "slimming", achieving dual breakthroughs in safety and energy density
Since its commercialization in 1991, lithium-ion batteries have become the main power source for mobile electronic devices, new energy vehicles, etc., and are closely related to today's social life. The increasing development of science and technology has raised higher requirements for the safety, energy density, and service life of traditional lithium-ion batteries while improving people's living standards.
Deep sea self pressurized solid-state battery system
Dr. Ju Jiangwei, associate researcher of the Chinese Academy of Sciences Qingdao Institute of Bioenergy and Process (hereinafter referred to as the "Qingdao Institute of Energy"), said that the cathode of traditional all solid state lithium batteries requires at least three components: cathode active materials, electron conduction and lithium ion conduction additives. The chemical reaction between different materials will reduce the battery performance.
We have innovatively developed a positive electrode material with ionic and electronic conductivity that is 3-5 orders of magnitude higher than traditional positive electrode active materials, and a specific capacity that exceeds current high nickel positive electrode materials, "said Ju Jiangwei." It has the functions of three materials at the same time, making the positive electrode of all solid state lithium batteries composed of only one material, avoiding the occurrence of adverse reactions
Technical principle diagram: Homogenized positive electrode has efficient mixed conductivity of electrons and lithium ions
It is reported that the material has high discharge capacity, small volume deformation, and excellent conductivity, which is more than 1000 times higher than traditional positive electrode materials, making all solid state lithium batteries work without relying on conductive additives. After the positive electrode is "slimmed down", the all solid state lithium battery still maintains 80% of its initial capacity after 5000 cycles, and its high energy density of 390Wh/kg (660Wh/L) is 1.3 times that of long cycle all solid state lithium batteries mentioned in current public data.
It is worth mentioning that traditional lithium-ion batteries use organic electrolytes as lithium ion transport media, which pose risks of volatilization, leakage, and explosion, limiting the breakthroughs in safety and energy density of traditional lithium-ion batteries. All solid state lithium batteries use non flammable and inherently safer solid electrolytes, with a thermal runaway temperature of over 300 ℃, greatly improving the safety of the battery; At the same time, solid electrolytes combined with high-voltage positive and low-voltage negative electrodes are expected to achieve a breakthrough in battery energy density of 400Wh/kg (traditional lithium-ion batteries have an energy density that is difficult to exceed 300Wh/kg).
The staff is conducting continuous preparation of electrode sheets
Therefore, as an emerging battery technology, all solid state lithium batteries are expected to overturn traditional lithium-ion battery technology, achieve breakthroughs in safety, energy density, service life and other performance, and provide safe and durable power sources for new energy vehicles, energy storage grids, deep-sea and deep space equipment, which is of great significance for the development of new energy storage systems. We are currently conducting Chinese style large-scale production and expect to achieve large-scale production within two to three years, "said Ju Jiangwei.
Solid state lithium battery soft pack cell
New material insights from 'obscure' papers
If the manufacturing of all solid state lithium batteries used to be like "mixing cocktails" in the past, now it only requires "a glass of pure water". The homogenization positive electrode technology proposed by the Solid State System Technology Center of Qingdao Energy Institute greatly simplifies the battery preparation process, significantly saves battery manufacturing costs, and helps the rapid commercialization of all solid state lithium batteries. It has milestone significance for the development of energy storage devices with high energy density and long service life, the development of new quality productivity, and the acceleration of China's construction of a new energy system.
However, for the R&D team, the starting point of this technology was actually a paper that had been neglected for over a decade. In 2008, Nobel laureate Goodenough proposed a material with enormous potential, but due to its high synthesis difficulty and unsatisfactory performance, it has not received the attention of scientists for more than a decade.
When we read this report from over a decade ago, we thought it was a very promising material. Because its composition was similar to a commonly used oxide electrolyte, it may have good ionic conductivity. We decided to first synthesize this parent material and then further innovate the material design based on it to achieve high electronic and lithium-ion conductivity, "recalled Ju Jiangwei.
Researchers are conducting battery analysis tests
However, the R&D team tried for over a year before finally obtaining the product, but when testing the material properties, the ion conductivity of this material was very low, completely different from the team's expectations. However, the electronic conductivity of the material is very high. Based on this, the R&D team changed their approach and used this parent material as a basis. Firstly, the successful doping of germanium element improved its ionic conductivity, but the electronic conductivity decreased.
At that time, we were once confused. After multiple discussions, we were inspired by the evolution of sulfur compounds and proposed using selenium to replace sulfur and narrow the band gap of the material to improve electronic conductivity. Eventually, we successfully obtained the material, "said Ju Jiangwei.
All solid state lithium batteries are expected to become an all-around player in the future energy storage field. It is reported that they can be applied in devices or equipment that require batteries, such as new energy vehicles and low altitude aircraft.
Solid state batteries undergo performance testing to ensure compliance with industry standards and user requirements
Tested and applied in the fields of new energy vehicles and deep-sea power sources
At present, the all solid state lithium battery developed by the R&D team has been tested and applied in the fields of new energy vehicles and deep-sea power sources.
Among them, the high-energy density all solid state lithium battery prepared by the National Key R&D Program for New Energy Vehicles during the 13th Five Year Plan period has successfully achieved vehicle installation demonstration and completed 10000 kilometers of fault free operation testing. In the deep-sea field, our developed solid state power supply system provides energy power for all sea deep landing vehicles such as Tianya, Haijiao, Wanquan, Canghai, and Fendou, reversing the awkward situation of China's cable powered 10000 meter all sea deep scientific examination. In addition, we are realizing the transfer and transformation of all solid state lithium battery technology in the form of pricing and equity investment, striving to promote and apply the results as soon as possible, "said Ju Jiangwei.
Qingdao Institute of Bioenergy and Process, Chinese Academy of Sciences (Shandong Energy Research Institute)
By the end of 2027, Qingdao Energy Institute will build a sulfide electrolyte production line with an annual production capacity of 10 tons of sulfide solid electrolyte powder and electrolyte membrane, and develop 20Ah grade sulfide solid soft pack batteries with a single energy density of over 400Wh/kg and a cycling performance of over 1000 times.
In the future, we plan to use the newly developed conversion type positive electrode material combined with metal lithium negative electrode to develop ultra-high energy density solid-state batteries with an energy density exceeding 700Wh/kg, and first realize their application in special fields
The technological breakthrough of all solid state lithium batteries is not only a microcosm of Shandong's technological innovation, but also provides a "Chinese solution" for the global energy transformation. When new energy vehicles bid farewell to "range anxiety" due to it, and when deep-sea scientific expeditions achieve "energy freedom" due to it, this technology that emerged from Shandong may reshape the power map of the future world.
Information source: Shandong Provincial Department of Science and Technology (official website)
