In view of this, governments and enterprises in many countries have accelerated their pace to deploy the "post-lithium battery" era. For example, some European institutions are committed to the development of magnesium and zinc batteries, and the CATL introduced sodium batteries. As the "Nihon Keizai Shimbun" magazine website pointed out in a recent report, the global competition for alternatives to lithium batteries has begun!
High cost of lithium battery
Lithium batteries were born in the 1960s and were commercialized by Sony Corporation in Japan in the 1990s. Compared with its "predecessors" nickel-hydrogen batteries and lead-acid batteries, lithium batteries can store more electrical energy. They have now flown into the homes of ordinary people. It is widely used in new energy vehicles, personal computers, smart phones and other products; it can also store solar and wind energy, making a world without fossil fuels possible.
In view of the tremendous contribution that lithium batteries have made to mankind, in 2019, three "fathers of lithium batteries" won the Nobel Prize in Chemistry. Lithium batteries have also become the "masters" in the battery industry today.
But the biggest disadvantage of lithium batteries is their high cost. It's just good for smart phones. If you need to store electrical energy on a large scale, you need a corresponding large battery. According to data from the Ministry of Economy, Trade and Industry of Japan, if you want the storage cost of a lithium battery power storage system to reach 23,000 yen (approximately 1,280 yuan) per kilowatt, which is the same as that of a pumped storage power station, it is simply a dream.
In addition, the production areas of lithium, nickel, and cobalt, the raw materials for lithium batteries, are extremely unevenly distributed, and the global lithium and cobalt deposits cannot be fully used for production. The reserves of lithium in the crust are 0.0065%, and the global reserves are only 86 million tons; in contrast, the reserves of sodium, magnesium, and zinc are much higher: the reserves of sodium in the crust are 2.74%, only China’s Qaidam The sodium salt reserves in the basin reach 321.6 billion tons; and the content of magnesium in the crust is as high as 13.9%.
Prospects for candidate elements are promising
Therefore, scientists have turned their attention to magnesium, zinc, sodium and other elements.
For example, the University of Cambridge in the United Kingdom, well-known universities of science and engineering in Denmark and Israel, and research institutions in Germany and Spain have jointly initiated a research project called the "EU Magnesium Interactive Battery Community" (E-Magic). This 4-year forward-looking project has received financial support from the European Union. The goal is to develop an environmentally friendly rechargeable magnesium battery with an energy density of more than 1,000 Wh/L (equivalent to twice that of a lithium battery).
The researchers said that this kind of battery uses metallic magnesium as the negative electrode. Because one magnesium ion carries two electrons, the capacity of the magnesium battery doubles compared with the lithium ion which can only carry one electron. It can be repeatedly charged and discharged more than 500 times.
It is reported that in 2020, the research group of Professor Yao Yan from the University of Houston in the United States and Toyota Research Center in North America successfully developed a very promising high-energy magnesium battery. Its potential applications include electric vehicles and storage batteries for renewable energy systems. Although the battery has only been charged and discharged continuously for more than 200 times, the research team believes that they have found a research direction for safer and higher-performance magnesium batteries: the positive electrode uses organic compounds and the negative electrode uses pyrenetetraketone (PTO) to achieve rapid And the reversible redox process, the weak coordination electrolyte based on boron clusters makes the ion movement faster. This advanced cathode and electrolyte design has great guiding significance for the development of magnesium batteries and will accelerate the pace of commercialization of magnesium battery technology.
In addition, Japan’s Tokyo Metropolitan University professor Kamimura Seishino has developed a battery that uses manganese oxide in the positive electrode and magnesium metal in the negative electrode. "Nihon Keizai Shimbun" reported that although the performance of magnesium batteries is still at a low level compared with lithium batteries, its potential is worth tapping. In the future, researchers will focus on solving the problem of electrolyte modification and strengthen the research of electrode materials.
Zinc is equally noticeable as magnesium. The new type of zinc-ion battery developed by Associate Professor Kobayashi Hiroaki and Professor Honma Kee of Tohoku University in Japan uses an aqueous solution as an electrolyte instead of traditional organic solvents and reduces the risk of battery fire. Researchers from the Pacific Northwest National Laboratory in the United States and the University of Munster in Germany have also collaborated to develop a "zinc metal dual-ion battery", which is composed of a zinc anode, a natural graphite cathode and a dual-ion salt solution.
In July of this year, China's CATL released a sodium battery with the world's highest energy density and ultra-fast charging characteristics (80% charge in 15 minutes). CATL is expected to continue to increase the energy density of sodium batteries and is expected to A basic industrial chain will be formed in 2023.
Lithium batteries have great potential to tap
Although the research on various alternative technologies is in full swing, judging from the current development situation, whether it is a magnesium battery, a zinc battery or a sodium battery, there are still many problems to be solved in terms of technology and materials. For example, magnesium ions are small in size, high in charge density, and strong in polarization. It is difficult to insert into most substrates, and it is difficult to form embedded compounds. Therefore, the choice of cathode materials is limited.
In view of this, there are also scientists who are committed to deeply tap the potential of lithium batteries, improve the performance of lithium batteries, and develop better quality lithium batteries.
According to a report from Nihon Keizai Shimbun, Japan’s Yuasa Company and Kansai University have developed a lithium-sulfur battery that uses sulfur as the positive electrode active material. Its mass and energy density can reach about twice that of existing lithium batteries. The mass energy density of lithium batteries commonly used in pure electric vehicles is about 200-300 Wh/kg, while the mass energy density of the lithium-sulfur battery developed this time exceeds 370 Wh/kg.
The researchers explained that theoretically the capacity of a lithium-sulfur battery can reach 8 times that of a traditional lithium battery under the same size, but there are problems such as low conductivity and easy soluble intermediate products in the electrolyte. The newly developed lithium-sulfur battery Sulfur batteries use microporous carbon particles to circumvent the above two problems. Yuasa stated that it hopes to increase the mass energy density of its lithium-sulfur batteries to 500 Wh/kg by 2023.