End-of-life (EOL) lithium-ion (Li-ion) battery waste from consumer electronics, electric vehicles (EVs), and large-scale energy storage systems continues to increase in volume while these technologies gain increasing popularity. Because state-of-the-art recycling methods tend to be energy intensive and cost ineffective, only a fraction of Li-ion battery waste becomes recycled. To ensure future availability of rare elements included in battery cathodes and to protect the environment, recycling facilities require a low-cost, low-energy, and negligible waste method to recycle Li-ion-battery cathodes. A researcher at NREL has developed a low-cost, low-energy, and negligible waste method to restore EOL Li-ion battery cathodes to a like-new relithiated condition. NREL’s method occurs at room temperature and facilitates autonomous relithiation by redox mediators without external process controls.
A critical component of cathode recycling is the efficient filling of vacancies in the cathode’s crystal structure, as the cathode materials, which are the lithium source in the battery, lose lithium ions by irreversible side reactions over time. A researcher at NREL has developed novel cathode recycling methods for lithium-ion (Li-ion) batteries, employing efficient cathode relithiation with low-cost, short-duration, and low-energy lithium-reinsertion techniques. In particular, redox mediators deliver lithium ions and electrons from the anode (e.g. Li metal) to the cathode materials with lithium vacancies. Next, the cathode materials adsorb/intercalate the lithium ions/electrons to fill the lithium vacancies. Finally, the redox mediators diffuse back to the anode and repeat the cycle, acting like charge shuttles.
To learn more about Cathode Recycling of End-of-Life Lithium Batteries, please contact Erin Beaumont at:
Applications and Industries
- Lithium-ion battery manufacturers
- Battery recycling facilities
- Auto manufacturers
- Grid-storage device manufacturers
- Personal/consumer electronics manufacturers
NREL’s lithium-ion-cathode recycling methods have the following advantages:
- Cathode relithiation is an autonomous process, so there is no need to control any electrochemical parameters.
- The selection of particular redox mediators determines the cell voltage, shuttling kinetics, and materials stability.
- Abundant choices exist for available redox mediators.
- The recycling process generates very little waste and does not produce another waste stream for recycling.
- The recycling process is very easy to scale up with batch or continuous operations possible.
- The recycling method is a room-temperature process, so there is no need to increase temperature and pressure, saving time, energy, and money.