Contact

  • Academic
    dfrivera@stanford.edu
    University - Student Department: Materials Science and Engineering Position: Graduate

Additional Info

  • Mail Code: 4034

All Publications

  • Substantial oxygen loss and chemical expansion in lithium-rich layered oxides at moderate delithiation. Nature materials Csernica, P. M., McColl, K., Busse, G. M., Lim, K., Rivera, D. F., Shapiro, D. A., Islam, M. S., Chueh, W. C. 2024

    Abstract

    Delithiation of layered oxide electrodes triggers irreversible oxygen loss, one of the primary degradation modes in lithium-ion batteries. However, the delithiation-dependent mechanisms of oxygen loss remain poorly understood. Here we investigate the oxygen non-stoichiometry in Li1.18-xNi0.21Mn0.53Co0.08O2-delta electrodes as a function of Li content by using cycling protocols with long open-circuit voltage steps at varying states of charge. Surprisingly, we observe substantial oxygen loss even at moderate delithiation, corresponding to 2.5, 4.0 and 7.6ml O2 per gram of Li1.18-xNi0.21Mn0.53Co0.08O2-delta after resting at upper capacity cut-offs of 135, 200 and 265mAhg-1 for 100h. Our observations suggest an intrinsic oxygen instability consistent with predictions of high oxygen activity at intermediate potentials versus Li/Li+. In addition, we observe a large chemical expansion coefficient with respect to oxygen non-stoichiometry, which is about three times greater than those of classical oxygen-deficient materials such as fluorite and perovskite oxides. Our work challenges the conventional wisdom that deep delithiation is a necessary condition for oxygen loss in layered oxide electrodes and highlights the importance of calendar ageing for investigating oxygen stability.

    View details for DOI 10.1038/s41563-024-02032-6

    View details for PubMedID 39420105

  • Calcination Heterogeneity in Li-Rich Layered Oxides: A Systematic Study of Li<sub>2</sub>CO<sub>3</sub> Particle Size CHEMISTRY OF MATERIALS Busse, G. M., Csernica, P. M., Lim, K., Lee, J., Jiang, Z., Rivera, D. F., Kim, Y., Shapiro, D. A., Gent, W. E., Chueh, W. C. 2023; 35 (24): 10658-10671

    View details for DOI 10.1021/acs.chemmater.3c02404

    View details for Web of Science ID 001133027400001