Lithium-ion battery (LIB) is featured by structural and chemical complexities across a broad range of length scales and, ultimately, it is the hierarchy of the battery structure that determines its functionality. The study of the battery function, degradation, and failure mechanisms requires a thorough and systematic investigation from the structural, chemical, mechanical, and dynamic perspectives. X-ray-based characterization techniques are playing an important role in this research field.

In this talk, I will review my group’s research activities over the past few years [1-10] by presenting a macro-to-nano zoom through the hierarchy of a standard battery cell [2] using a suite of state-of-the-art X-ray techniques. Damage [6-7], deformation, compositional [9-10] and chemical [1, 4-5] heterogeneity at different length scales are visualized and are associated to different degradation phenomena and mechanisms. Our results highlight the importance of the battery cathode material’s mechanical properties [7-8], which evolve upon battery cycling and could significantly impact both the immediate and the long-term cell behaviours. Statistical analysis, numerical modelling [4], and machine learning [3, 5-6] approaches are key components integrated in our research efforts and will be touched upon in this presentation. I hope this presentation will ignite enthusiasm and ideas for future collaborations.

References:

(1) J. Zhang et al., Nat. Commun. 11 (2020) 6342.

(2) G. Zan et al., J. Mater. Chem. A (2021) DOI: 10.1039/D1TA02262H.

(3) Z. Jiang et al., Nat. Commun. 11 (2020) 2310.

(4) S. Li et al., Nat. Commun. 11 (2020) 4433.

(5) G. Qian et al., ACS Energy Lett. 6 (2021) 687–693.

(6) Y. Mao et al., Adv. Func. Mater. (2019) 1900247.

(7) S. Xia et al., Nano Energy 53 (2018) 753-762.

(8) C. Wei et al., Acc. Chem. Res. 51 (2018) 2484-2492.

(9) J.-N. Zhang et al., Nat. Energy 4 (2019) 594–603.

(10) F. Lin et al., Nat. Energy 1 (2016) 15004.