DENDRITES ON LITHIUM-METAL BATTERIES: A NUMERICAL APPROACH TO THE EFFECT OF THE MORPHOLOGY ON THE NMR SPECTRUM

MALDONADO OCHOA, SANTIAGO AGUSTÍN; VACA CHÁVEZ, FABIÁN; OTERO, MANUEL; ZAMPIERI, MURIEL

Workshop; AMPERE NMR SCHOOL 2021; 2021

Lithium metal is considered the ultimate anode for lithium based batteries, due to, for instance, its high theoretical capcity (3860 mAhg-1) compare with the currently used graphite [1]. However, this electrode presents several drawbacks that compromise the battery security and performance, such as the growth of lithium microstructures (dendrites) during the charge/discharge process. Great efforts are made to overcome those issues by proposing strategies for dendrite suppression and regulation. Therefore, it is crucial to have characterization tools to monitor the growth of dendrites throughout the cycles. In this sense, Nuclear Magnetic Resonance emerges as a powerful non-invasive technique capable of detecting the formation of dendrites [2]. Although it is possible to detect the presence of microstructures, interpretation of the spectra is not straightforward because different morphologies can lead to similar results [3]. The shape of the spectrum depends on the perturbations of the local magnetic field produced by the dendrites in presence of the static magnetic field, and a better interpretation of the spectrum can be achieved by means of numerical calculations of such perturbations. In this work, we performed those computations using the fourier based method developed by Salomir et al. [4]. This calculations allow us to study the effect of the dendrites on the NMR spectrum as a function of the density, height and width of the mictrostructures. We found that the most important factor is the density of dendrites, as suggested by Küpers et al. [3]. This simulations can also be useful for the assessment of multipulse sequences, such as proposed by Ilott et al [5], which could be used to enhance the microstructures signal.References[1] X. Zhang, A.Wang, X. Liu, J. Luo. Acc. Chem. Res. 2019, 52, 11, 3223?3232[2] R. Bhattacharyya, B. Key, H. Chen, A.S Best, A.F Hollenkamp, C.P Grey. Nature Mater., 2010, 9, 504?510.[3] V. Küpers, M. Kolek, P. Bieker, M. Winter, G. Brunklaus. Phys. Chem. Chem. Phys., 2019,21, 26084-26094.[4] R. Salomir, B.D de Senneville, C.T. Moonen. Concepts Magn. Reson., 2003, 19B, 26-34. [5] A.J Ilott, A. Jerschow. Sci. Rep., 2017, 7, 5425.