Cobalt: A Key Player in Batteries and Vibrant Blue Hues

Ranked 27th on the periodic table, cobalt is a crucial component in rechargeable batteries and jet engines. In 2018, the U.S. Department of Interior identified it as one of 35 critical minerals vital to the nation’s economy. Its importance is heightened by its status as a national security concern, as the majority is mined in a politically unstable African region and processed in China.

Discover the fascinating journey of this versatile metal, once celebrated for its role in crafting stunning blue ceramics and now indispensable for the evolution of electric vehicles. We’ll begin with a touch of historical lore.

Cobalt Got Its Name from Gnomes

Hundreds of years ago, miners in the Schneeberg mountains, now part of Germany, encountered a persistent issue. While digging for silver and nickel-rich ore, they found that an unknown impurity disrupted the smelting process, preventing them from extracting the valuable metals.

Living in the Middle Ages, the miners attributed their smelting troubles to mischievous kopelts or kopolds, terms from medieval German folklore meaning "gnome" or "goblin." Legend has it that these creatures inhabited the Schneeberg mines, playing tricks by substituting silver and nickel with a harmful mineral that emitted toxic fumes during smelting. They were also accused of causing cave-ins.

Like many ancient tales, the gnome legend held a kernel of truth. The smelting process was indeed hindered by high levels of naturally occurring cobalt in the Schneeberg ore. Additionally, a mineral called cobaltite, containing arsenic and sulfur, posed deadly risks when released in confined mine shafts.

The elemental metal cobalt was first isolated and named in 1735 by Swedish chemist Georg Brandt, a skeptic of alchemy and likely no believer in gnomes.

Ancient Egyptians and Chinese Loved Cobalt Blue

Long before cobalt was named in the 18th century, its vibrant blue pigments and dyes were highly valued for thousands of years.

According to the Cobalt Institute, artifacts such as pottery and glass adorned with cobalt-based glazes have been discovered in Egyptian tombs, some as old as 2,600 years. Similarly, the renowned blue porcelain from China’s Tang (600-900 C.E.) and Ming (1350-1650 C.E.) dynasties also featured cobalt-based mineral glazes.

While pure cobalt appears as a lustrous gray metal, it can be converted into a vivid blue powder through calcination. This process involves heating cobalt oxides at temperatures exceeding 2,012 degrees Fahrenheit (1,100 degrees Celsius). The iconic Cobalt Blue is created by heating cobalt oxide (Co₃O₄) with aluminum silicates at 2,192 degrees Fahrenheit (1,200 degrees Celsius).

A variety of shades, such as mazarine blue, willow blue, and blue-black, can be produced by mixing cobalt oxide with different minerals. Additionally, small quantities of cobalt blue are utilized as a "decolorizer" to neutralize yellowish tints in glass caused by iron impurities.

Until the 20th century, cobalt was primarily used in pigments and paints. In 1916, over 70 percent of the global cobalt production, totaling just 440 tons (400 metric tons), was consumed as oxides for coloring purposes, as reported by the Cobalt Institute.

Half the World's Cobalt is Used for Rechargeable Batteries

The lithium-ion batteries in your smartphone, tablet, and electric vehicle rely partly on cobalt. This metal, alongside lithium, nickel, and manganese, is a crucial component in these high-performance batteries that fuel our digital lifestyles. Approximately 50 percent of the world’s cobalt supply is dedicated to rechargeable battery production.

Cobalt is a key component in the cathode, the positively charged electrode of lithium-ion batteries. During charging, lithium ions move from the cathode to the anode, the negatively charged electrode, where they are stored. When the battery discharges, these ions return to the cathode, releasing electrons that power devices like phones or electric motors.

Cobalt’s natural properties, such as thermal stability and high energy density, make it perfect for battery use. Cobalt-based cathodes resist overheating and combustion, addressing critical safety concerns, while also enabling greater energy storage and transfer. Beyond lithium-ion batteries, cobalt is also used in other rechargeable types like nickel-cadmium and nickel-metal hydride batteries.

With cobalt comprising 10 to 33 percent of rechargeable battery cathodes, the automotive industry will require significantly more cobalt to support the growing electric vehicle market. Estimates suggest that cobalt demand for passenger vehicles will surge from over 27,500 tons (25,000 metric tons) in 2020 to more than 110,231 tons (100,000 metric tons) by 2025.

It's Super-Useful in Superalloys

Aerospace engineers rely on cobalt-based "superalloys" for materials that can endure the extreme temperatures inside jet and rocket engines.

Superalloys, known for their exceptional durability, are high-performance metals renowned for their ability to withstand extreme heat and wear. Nickel-based superalloys excel in stress resistance at temperatures up to 1,706 degrees Fahrenheit (930 degrees Celsius). However, cobalt-based superalloys surpass them at even higher temperatures.

Cobalt boasts a higher melting point than nickel, and its superalloys are superior in resisting heat-induced corrosion. This makes cobalt superalloys ideal for the stationary fins in gas-turbine engines, where they endure the extreme heat of jet engines without degrading.

It's Mostly Mined in One Troubled Country

Cobalt's inclusion on the U.S. Department of Interior's list of 'critical minerals' for national security is largely due to the fact that 50% of the world's cobalt is mined in the Democratic Republic of Congo (DRC). The U.S. Geological Survey highlights issues such as government corruption, human rights abuses, and environmental harm linked to cobalt mining in the DRC.

Unsafe and unethical labor practices in unregulated 'artisanal' cobalt mining in the DRC have drawn concern not only from human rights organizations like Amnesty International but also from global stakeholders. The political and environmental instability in the DRC poses a significant risk to the cobalt supply chain, which is crucial for rechargeable batteries. Any disruption in the DRC could have far-reaching effects on the global high-tech economy.

According to the USGS report, China plays a dual role as the primary refiner of cobalt and a major financier of large-scale cobalt mining projects in the DRC. This leaves the U.S. tech industry heavily reliant on both an unstable supply from the DRC and a politically sensitive trade relationship with China, underscoring the final point on our list.

The U.S. Is Getting Into Cobalt Mining

Data from 2015 reveals that the United States accounted for 10 percent of global cobalt consumption but contributed less than 1 percent to the world's cobalt production.

While cobalt is not exceedingly rare, ranking 32nd in abundance within the Earth's crust, it is not widely distributed. Only two mines, located in Canada and Morocco, are capable of extracting pure cobalt ore. Most cobalt is obtained as a byproduct of copper and nickel mining, with the DRC's Central African Copperbelt hosting one of the richest cobalt deposits globally.

The U.S. faces challenges in cobalt mining due to limited high-grade deposits, making profitable extraction difficult. Additionally, the mining sector has criticized the slow permitting process for mineral exploration, both on land and offshore. To reduce dependence on foreign sources of critical minerals like cobalt, the Trump administration has instructed the Department of Interior to expedite the permitting process.

Although the U.S. faces permitting and geological challenges, advancements in cobalt mining have been made. In 2014, the Eagle Mine in Michigan's Upper Peninsula started extracting nickel and copper, with cobalt and other minerals as secondary products. Additionally, the nation's first cobalt-specific mine is set to begin operations in 2020 in Idaho.