Nowadays, all kinds of lithium batteries have become indispensable devices in daily life. Whether it is mobile phones, computers, wearable devices or new energy vehicles, its application has become more and more extensive. However, the ensuing concerns about lithium battery resources, especially the soaring prices of lithium battery related raw materials since this year, have forced countries to speed up the layout of the "post lithium battery" era.
Multi Country bet on magnesium battery
"Nihon Keizai Shimbun" website on the 20th with "when will lithium batteries be surpassed?" It is reported that the joint research team "e-magic" composed of Cambridge University in the UK, well-known engineering universities in Denmark and Israel and research institutions in Germany and Spain, with the financial support of the EU, is accelerating the development of breakthrough magnesium and zinc batteries with high capacity and better environmental protection with the goal of 2030.
According to the report, the lithium battery was first commercialized by Sony Corporation of Japan in the 1990s. It can store more electric energy than the previous nickel hydrogen battery and lead-acid battery. Now it has been popularized in new energy vehicles, personal computers, smart phones and other products. Relevant research also won the Nobel Prize in Chemistry in 2019. But the biggest disadvantage of lithium battery is its high cost. For example, if lithium batteries are used as energy storage batteries for large-scale storage of renewable energy such as solar energy or wind energy, the data of Japan's Ministry of economy and industry show that it is "a daydream" to reduce its cost to 23000 yen per kilowatt hour equivalent to hydropower.
Therefore, the main goal of the "post lithium battery" era is to reduce costs and improve durability. "E-magic" aims at lower cost magnesium batteries. Magnesium ions can carry two positive charges, while lithium ions can only carry one. Therefore, in theory, the energy density of magnesium batteries can be greater than that of lithium batteries. At present, the magnesium battery in the laboratory has been able to charge and discharge repeatedly for more than 500 times. Researchers will focus on improving electrolyte and developing new electrode materials. At the same time, Toyota's North American Research Institute and the University of Houston are also developing new magnesium batteries. Its electrode cathode material adopts organic compounds and its electrolyte adopts boron. Although the magnesium battery can only be charged and discharged 200 times at present, the research team said that "the direction of developing high stability and high-performance batteries has been found".
In addition to magnesium batteries, the report mentioned that assistant professor hiroming Kobayashi and Professor benjiange of Tohoku University in Japan are also developing new zinc batteries. They use aqueous solution to replace organic solvent as electrolyte, which reduces the risk of fire accidents. Due to its low cost, it is expected to be used to save renewable energy power in the future.
Alternative technologies are not yet mature
In an interview with the global times on the 21st, Moke, chief analyst of true lithium research, said that in terms of the lithium battery replacement technology currently being developed, there are relatively more mature sodium batteries in addition to the magnesium batteries and zinc batteries mentioned by the Japanese media. In fact, both sodium ion batteries and lithium-ion batteries originated in the 1970s, and their working principles are highly similar. However, due to the lack of appropriate electrode materials, sodium battery did not make a breakthrough until 2000. At present, the most advanced sodium battery is released by China Ningde times in July this year. It has the highest energy density in the world (160wh / kg) and ultra fast charging characteristics (80% rechargeable in 15 minutes). It is estimated that the energy density of the next generation sodium battery in Ningde era can exceed 200wh / kg; It is planned to form a basic industrial chain in 2023.
Merco believes that from the current development situation, whether magnesium battery, zinc battery or sodium battery, there is still a considerable gap between its maturity and large-scale commercial application, even just in the laboratory stage, and there are many defects in its performance. He said that the core reason why the outside world is so enthusiastic about these lithium battery alternative technologies is not their better performance, but richer resources and cheaper raw materials.
As Japan economic news mentioned, the origin distribution of lithium battery raw materials - lithium, nickel and cobalt is extremely uneven. Relevant data show that nearly 80% of the output of lithium resources is mainly concentrated in the four lakes in the Americas and the six mines in Australia, and more than 80% of the lithium resources needed by China need to be imported; Most nickel resources are concentrated in Indonesia, Australia, Brazil, Russia, Cuba and the Philippines. The nickel reserves of these six countries account for nearly 78% of the global reserves; About 51% of the world's proven cobalt resources are distributed in the Democratic Republic of the Congo. In contrast, the reserves of sodium, magnesium and zinc are much higher. For example, the reserves of lithium in the earth's crust are 0.0065%, the global reserves are only 86 million tons, while the reserves of sodium in the earth's crust are 2.74%, and the sodium salt reserves in China's Qaidam Basin alone reach 321.6 billion tons.
However, on the other hand, there are still many obstacles to be overcome in technology and materials of magnesium battery and zinc battery. At present, a more suitable electrode material has not been found, let alone large-scale application. It is predicted that it will take another 30 years from the development of these new technologies to mass production. He also said that even relatively mature sodium batteries are limited in the improvement of energy density due to the relatively large radius and volume of sodium ions, which may be more suitable for energy storage batteries, two wheeled electric vehicles and other fields with low requirements for energy density. Ningde times revealed that it has developed a system shared by sodium battery and lithium battery, which can "learn from each other".
Lithium batteries can also "tap the potential"
If lithium battery is still difficult to replace in a short time, what about its future? Merco believes that the soaring price of raw materials related to lithium batteries this year has been artificially hyped. In terms of the reserve of lithium resources alone, although it is far less than sodium magnesium zinc, it will be absolutely sufficient in the next 30 to 50 years.
At the same time, the potential of lithium batteries is far from being tapped. Merco said that the theoretical energy density of lithium batteries can reach up to 700wh / kg. At present, the energy density of high nickel 811 batteries (i.e. nickel accounts for 80%, cobalt accounts for 10% and manganese accounts for 10%) can reach 260-270wh / kg. However, Japan and South Korea's head battery enterprises have launched ultra-high nickel battery products with nickel content of more than 90% in 2021. Coupled with the use of silicon carbon materials for the cathode, it is expected to increase the energy density to 400wh / kg, The storage capacity of lithium battery is increased by 50%. In addition, many countries are also studying replacing the liquid electrolyte of lithium battery with solid electrolyte, which can improve its energy density and safety at the same time.
