Texas University develops manganese-based sodium-ion batteries or will reduce the cost of electric vehicle batteries

According to foreign media reports, lithium-ion batteries have become mainstream battery products in the market, and many smart phones and electric vehicles have adopted such batteries. However, the University of Texas (Dallas) and the Seoul National University of Korea jointly developed a new battery that uses manganese and sodium-ion-based materials. )material. The material may reduce the cost of the battery and is more eco-friendly, and the battery produced can be used by electric vehicles.

Professor Kyeongjae Cho of Materials Science and Engineering at Erik Jonsson School of Engineering and Computer Science, a division of the University of Texas at Dallas, said battery costs are a real issue that needs to be addressed.

With the increasing demand from manufacturers and users for electric vehicles, Lithium Battery production is likely to be unsustainable and unable to meet the growing demand for products. According to a recent report released by the International Energy Agency, the number of electric vehicles in the world will reach 9 million to 20 million by 2020; by 2025, the number of electric vehicles in the world will reach 40 million. 70 million vehicles, the actual number of electric vehicles will depend on relevant national policies.

If sodium is used, it is expected to reduce the battery cost of electric vehicles, because the price of sodium is relatively cheap, and the reserves are abundant, but there are also some drawbacks.

Cho said: "Lithium is more expensive, mineral resources are limited, there are only a few lithium mines in the world. But sodium does not have the problem of insufficient minerals, it can be extracted from seawater. Unfortunately, despite the price ratio of sodium ion batteries Lithium-ion batteries are cheap, but the energy density of sodium is 20% lower than that of lithium. The energy density (or energy storage capacity) of a battery directly determines the running time of equipment such as electric vehicles.

The battery usually consists of a positive electrode (anode) and a negative electrode (cathode) and an electrolyte between the two. In a standard lithium ion battery, the anode is composed of lithium, cobalt, nickel, and oxygen, and the cathode is composed of graphite (a form of carbon). When the battery is charged, lithium ions move from the anode to the cathode and adhere to the carbon. When the battery is discharged, lithium ions return to the anode to provide power to the device.

Cho said: "As early as a few years ago, it was expected to add manganese oxide materials to the anode of lithium-ion batteries, thereby increasing the battery's power. Unfortunately, the state of the battery was not stable when tested."

According to the design of Cho and his colleagues, they replaced the lithium, the most abundant material in the anode, with lithium, and replaced the more expensive and more scarce cobalt and nickel with manganese.

Cho declared: “The sodium ion materials we have developed and designed are more stable, and their battery capacity is comparable to that of lithium-ion batteries. We believe that these batteries are scalable. To this end, we hope that the industry can adopt such new materials and gradually realize Commercial mass production."

Based on an in-depth study of the physical and chemical properties of other experimental materials, the research team used a reasonable ratio of raw materials and overcome the above technical problems. They first used computer simulations to determine the configuration of the atoms for the best performance of the battery, and then conducted extensive material testing in the lab until the development was successful.