Chemomechanics is an old subject, yet its importance has been revived in rechargeable batteries where the mechanical energy and damage associated with redox reactions can significantly affect both the thermodynamics and rates of key electrochemical processes. Thanks to the push for clean energy and advances in characterization capabilities, significant research efforts in the last two decades have brought about a leap forward in understanding the intricate chemomechanical interactions regulating battery performance. Going forward, it is necessary to consolidate scattered ideas in the literature into a structured framework for future efforts across multidisciplinary fields. This review sets out to distill and structure what the authors consider to be significant recent developments on the study of chemomechanics of rechargeable batteries in a concise and accessible format to the audiences of different backgrounds in electrochemistry, materials, and mechanics. Importantly, we review the significance of chemomechanics in the context of battery performance, as well as its mechanistic understanding by combining electrochemical, materials, and mechanical perspectives. We discuss the coupling between the elements of electrochemistry and mechanics, key experimental and modeling tools from the small to large scales, and design considerations. Lastly, we provide our perspective on ongoing challenges and opportunities ranging from quantifying mechanical degradation in batteries to manufacturing battery materials and developing cyclic protocols to improve the mechanical resilience.

Single-crystalline nickel-rich cathodes are a rising candidate with great potential for high-energy lithium-ion batteries due to their superior structural and chemical robustness in comparison with polycrystalline counterparts. Within the single-crystalline cathode materials, the lattice strain and defects have significant impacts on the intercalation chemistry and, therefore, play a key role in determining the macroscopic electrochemical performance. Guided by our predictive theoretical model, we have systematically evaluated the effectiveness of regaining lost capacity by modulating the lattice deformation via an energy-efficient thermal treatment at different chemical states. We demonstrate that the lattice structure recoverability is highly dependent on both the cathode composition and the state of charge, providing clues to relieving the fatigued cathode crystal for sustainable lithium-ion batteries.

Understanding interactions between cell-penetrating peptides and biomembrane under tension can help improve drug delivery and elucidate mechanisms underlying fundamental cellular events. As far as the effect of membrane tension on translocation, it is generally thought that tension should disorder the membrane structure and weaken its strength, thereby facilitating penetration. However, our coarse-grained molecular dynamics simulation results showed that membrane tension can restrain polyarginine translocation across the asymmetric membrane and that this effect increases with increasing membrane tension. We also analyzed the structural properties and lipid topology of the tensed membrane to explain the phenomena. Simulation results provide important molecular information on the potential translocation mechanism of peptides across the asymmetric membrane under tension as well as new insights in drug and gene delivery.

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Defects are pervasive in electrochemical systems across multiple length scales. The defect chemistry largely differs from the bulk behavior and often dictates the rate performance for battery materials. However, the impact of material defects on Li kinetics remains elusive because of their complex nature and the sensitivity of the reaction kinetics on the local atomic environment.Here we focus on the grain boundaries (GBs) in layered-oxide cathodes and address their role in Li transport using the firstprinciples theoretical approach. We construct the coincidence site lattices of ∑2(11̅ 04̅ ), ∑3(1̅ 102̅ ), ∑5(11̅ 01̅ ), and ∑9(1̅ 104̅ ) GBs. The energy profiles for Li migration across and along the grain planes are plotted. We discuss in detail how the atomistic features associated with various grain structures such as the local structural distortion and charge redistribution determine the Li transport kinetics. Specifically, the coherent ∑2 GBs facilitate Li migration with 1−2 orders of magnitude increased diffusivity than the bulk diffusion, the asymmetric ∑3 GBs significantly impede Li diffusion, and the locally disordered ∑5 and ∑9 GBs cause slightly increased Li diffusivity at the intermediate diffusion distance (∼15 Å). We further evaluate the overall Li diffusivity and conductivity in the layered-oxide lattice by a distinction of Li transport in the bulk, across the GBs, and along the grain planes. The fundamental understanding sheds insight on a prevalent defect in the state-of-the-art cathode and its potential optimization of Li kinetics.