In 1980, John Goodenough invented the first lithium-ion rechargeable battery needing cobalt in Oxford. Experiments have shown that cobalt has a very high energy density and is particularly suitable for batteries that are small but require large amounts of energy. Goodenough heats the leading part by himself. To extract cobalt.
Figure 丨 John Goodenough
Today, most commercial lithium-ion batteries use cobalt, but it is expensive. To this end, it derives a black interest chain: For a long time, there have been human rights violations in the Republic of Congo, including the use of child labor mining. Behavior. Electronic equipment and electric vehicle companies are reluctant to pay big prices for manufacturing, and they are unwilling to participate in local human rights exploitation. So they gradually reduce the amount of cobalt used in batteries. Tesla’s battery supplier Matsushita Electric Co., Ltd. They announced at the end of last month that they are developing batteries that do not require cobalt. Goodenough and other researchers who have developed cobalt-free batteries are also helping Panasonic.
The battery has a positive electrode, usually graphite, and a negative electrode, a composition of lithium, cobalt, and oxygen. In battery packs for electric vehicles, the negative electrode portion often contains more nickel than the electronic product, which reduces cobalt. Use, but it brings higher processing costs and is more likely to cause fires on the aircraft - for example, the battery in the Samsung Note 7. In contrast, the electrons on the outer orbits of cobalt atoms are distributed in pairs. , This means it is small and dense, and it is easy to form a layer.
Figure 丨 Raw Cobalt Copper Ore
But new generation battery researchers, including Goodenough, are turning to the study of materials such as manganese and iron. Unlike layered structures, these elements form a 'rocksalt' structure. Negative electrodes containing rock salt are already in some The device is used, but currently the rock salt structure does not yet have the same high energy density as cobalt or nickel.
Researchers and companies are ready for alternatives. 'Because cobalt is expensive, companies try not to use it in battery manufacturing', said Goodenough, professor of engineering at the University of Texas. In the past two years, cobalt has The price has quadrupled. At this stage, portable electronic devices use most of the cobalt on the market, and the future demand for cobalt for electric vehicle battery packs will be nearly 1,000 times higher than that of mobile phones. With global warming, the More and more people are replacing internal combustion engine-driven cars with electric ones. Although this is a good thing for the Earth, it actually pushes up the price of cobalt.
Cobalt is a by-product of the production of other metals such as nickel and copper, but it also exists in its own form in the earth's crust, mainly in the mines in the Democratic Republic of the Congo. In 2016, the Washington Post conducted an opaque cobalt supply chain in the past. The investigation revealed the situation of child labor employment and the lack of necessary mining equipment.
It is true that there are other ways to avoid dangerous mining: Recycling of cobalt. However, since lithium-ion batteries have a long life and people’s demand for electronic products will increase, it’s important to purchase lithium-ion batteries in the next 10 years. People will increase significantly, said Elsa Olivetti, an energy research expert from the Massachusetts Institute of Technology. In October last year, she published an article that concluded that the supply of cobalt will grow rapidly to meet the needs of the next few years. With the rise of electric vehicles, despite the progress in the development of new negative materials and the open source of cobalt in the past eight months, she still wrote: 'Currently, cobalt electrodes still exist and have been studied. But People have begun to gradually reduce the use of cobalt elements. The use of stable, energy-intensive metals such as phosphorus and iron to make battery negative electrodes will be the future trend.
In addition to stratified and rock salt-structured batteries, researchers are developing solid-state batteries. Such batteries may require more lithium, but not necessarily cobalt, and are much safer than existing lithium-ion batteries. BMW, Toyota, Honda, and other auto companies are studying these batteries, but Olivetti believes the technology will not meet market demand in 2025. Prior to this, the company will try to reduce the use of cobalt-containing batteries. Companies such as Apple and Samsung have joined the Responsible Cobalt Initiative The plan promises to improve the environmental pollution and adverse social impacts produced in the production of cobalt. Recently, Apple has begun to purchase cobalt directly from the miners to ensure that the cobalt supplier's production safety conditions meet industry requirements.
Goodenough, 96 years old, is still thinking about the use of cobalt. Although he has developed a battery that does not require cobalt, he still does not think lithium batteries using cobalt will withdraw from the stage of history. Despite the high production costs, he designed lithium batteries in his early years. Still has a very good application potential.
