For many years battery researchers around the world have been researching ways to eliminate the need for cobalt from high-energy batteries used in various electronic devices. The reason such effort is being put into eliminating cobalt from batteries is due to the high cost of the material and human rights. The problem with removing cobalt so far has been that matters created about the material habit lived up to the performance standards of batteries that use cobalt.
University of Texas researchers from the Cockrell School of Engineering say that they have solved the problem of a cobalt-free high-energy lithium-ion battery that eliminates cobalt. The breakthrough has the potential to reduce the cost of producing batteries while boosting performance in some ways. Specifically, the team has a new class of cathodes, which is the electrode in a battery where all the cobalt typically resides, that uses a high nickel content. The cathode in the study is 89% nickel but also contains manganese and aluminum.
The more nickel there is in a battery, the more energy it’s able to store. Increased energy density can lead to longer battery life for whatever the device is using the battery. That could mean longer runtime for a smartphone or longer driving distance for an electric car.
The researchers overcame some of the downsides of cobalt-free batteries, such as short lifecycle and poor rate capability issues using an optimal combination of metals to ensure an even distribution of ions. Cobalt is extremely expensive at about $28,500 per ton, making it more expensive than nickel, manganese, and aluminum combined. Typically cobalt makes up 10 to 30% of lithium-ion battery cathodes.
The key to the breakthrough resides at the atomic level. Researchers were able to ensure the ions of the various metals are evenly distributed across the cathode’s crystal structure during synthesis. When the ions bunch up, performance degrades, so keeping the ions evenly distributed avoids performance loss. The researchers say that ultimately they have lowered the cost of creating batteries and increase the energy density without sacrificing cycle life.