In 1980, John Goodenough invented the first lithium-ion battery in Oxford that required cobalt. Experiments have shown that cobalt has a very high energy density, which is especially suitable for small but high-energy batteries.
Cobalt is now used in most commercial lithium-ion batteries, but it is expensive, and for that, it spawned a black profit chain. Human rights violations, including the use of child labor in mining, have long existed in the Republic of Congo. Electronics and electric-car companies are reluctant to pay high prices for manufacturing and participate in local human rights abuses, so they began to use less cobalt in their batteries. Panasonic, Tesla's battery supplier, announced late last month that it is developing batteries that do not require cobalt and researchers such as Goodenough who has developed cobalt-free batteries are also helping Panasonic.
The battery has a positive electrode, usually graphite, and a negative electrode, a composite of lithium, cobalt, and oxygen. In the battery pack of an electric car, the negative part often contains more nickel than the electronic part, which has reduced cobalt use but has resulted in higher processing costs and a greater risk of fire on airplanes, such as the battery in the Samsung Note 7. In contrast, electrons in the outer orbital of cobalt atoms are paired, which means it is small, dense and easily layered.
But a new generation of battery researchers, including Goodenough, is turning to materials like manganese and iron. Unlike layered structures, these elements form a rocksalt structure. The negative electrode containing rocksalt has been used in some devices, but the rocksalt structure does not have the same high energy density as cobalt or nickel.
Apart from the layered and rocksalt batteries, researchers are developing solid-state batteries, which may require more lithium, but not necessarily cobalt, and are much safer than existing lithium-ion batteries. Car companies such as BMW, Toyota, and Honda are working on the batteries, but Olivetti, the energy research expert at MIT, doesn't think the technology will be ready for the market in 2025. Until then, the companies will try to reduce the use of cobalt batteries. Companies such as Apple and Samsung have joined the Responsible Cobalt Initiative, which promises to improve environmental pollution and adverse social impacts from Cobalt production. Recently, Apple has started buying cobalt directly from miners to ensure that cobalt suppliers meet industry safety requirements.