@article{35884,
  author = {KyuJung Jun and Lori A Kaufman and Wangmo Jung and Byungchun Park and Chiho Jo and Taegu Yoo and Donghun Lee and Byungju Lee and Bryan D McCloskey and Haegyeom Kim and Gerbrand Ceder},
  title = {Understanding the Irreversible Reaction Pathway of the Sacrificial Cathode Additive Li6CoO4},
  abstract = {<p><span>The use of a sacrificial cathode additive that contains a large amount of lithium is one potential solution to compensate for the irreversible capacity loss associated with next-generation anodes such as silicon. Antifluorite-type Li</span><sub><span>6</span></sub><span>CoO</span><sub><span>4</span></sub><span>&nbsp;has attracted attention as a potential cathode additive owing to its remarkably high theoretical lithium extraction capacity. However, the complex mechanism of lithium extraction as well as the oxygen loss from Li</span><sub><span>6</span></sub><span>CoO</span><sub><span>4</span></sub><span>&nbsp;is not well understood. A generalizable computational thermodynamics and experimental framework is presented to understand the lithium-extraction pathway of Li</span><sub><span>6</span></sub><span>CoO</span><sub><span>4</span></sub><span>. It is found that one lithium per formula unit can be topotactically extracted from Li</span><sub><span>6</span></sub><span>CoO</span><sub><span>4</span></sub><span>, followed by an irreversible and nontopotactic phase transformation to Li</span><sub><span>2</span></sub><span>CoO</span><sub><span>3</span></sub><span>&nbsp;or LiCoO</span><sub><span>2</span></sub><span>&nbsp;depending on the temperature. The results show that peroxide species may form to charge-compensate for Li extraction which is undesirable as this can lead to gas release during battery operation. It is suggested that charging Li</span><sub><span>6</span></sub><span>CoO</span><sub><span>4</span></sub><span>&nbsp;at an elevated temperature that the electrolyte can withstand, redirects the reaction pathway and prevents the formation of intermediate peroxide species making it an effective and stable sacrificial cathode additive.</span></p>},
  year = {2023},
  journal = {Advanced Energy Materials},
  month = {06/2023},
  issn = {1614-6832},
  url = {https://onlinelibrary.wiley.com/doi/10.1002/aenm.202301132},
  doi = {10.1002/aenm.202301132},
  language = {eng},
}