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The all-solid-state lithium-ion battery (ASSLIB) is a promising candidate for next-generation rechargeable batteries due to its high-energy density and potentially low risk of fire hazard compared with that of traditional lithium-ion batteries. However, the widespread application of ASSLIBs is unfortunately hindered by new critical issues arising from the all-solid-state structure, especially mechanical instability. First, employing solid electrolytes (SEs) in ASSLIBs is accompanied by a reduction of cell compliance. The SEs are normally much stiffer than liquid electrolytes, and they are no longer able to effectively accommodate the swelling and shrinkage of active particles during (de)lithiation. This may lead to the interfacial delamination and fragmentation of the active particles and electrolytes. In addition, although SEs are expected to mechanically suppress the growth of lithium dendrites at the lithium metal (Li)/SE interface, lithium dendrites are still observed frequently in battery cells employing SEs even with high stiffness. Hence, comprehending these phenomena and providing solutions to these issues are crucial to promote the application of ASSLIBs. A number of theoretical models have been developed to investigate the chemo-mechanical behavior of ASSLIBs in recent decades. This mini-review aims to comprehensively review them, focusing on the mechanically informed modeling on two main topics: (1) lithium dendrite initiation at the Li/SE interface and propagation through SEs and (2) delamination and fragmentation within a composite electrode due to (de)lithiation of an active particle. With this mini-review, we want to supply a more nuanced understanding for chemo-mechanical behavior at different interfaces in ASSLIBs from a modeling perspective.

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The coupling relationship between polymer gel system and reservoir pores is an important basis for scientific formulation of tertiary oil recovery programs. The polymer gel profile control agent can significantly modify the fluid migration path inside the reservoir. In this study, artificial cores were used to carry out indoor water flooding experiments after polymer gel injection that considering formation permeability, polymer concentration and polymer injection rates. Based on the accurate records of the breakthrough pressure and injection volume during water flooding, as well as a large number of observations of the microscopic morphology of the cores after the polymer gel profile control and displacement, a set of criteria for determining reservoir-matched polymer gel profile control agents is proposed. The experimental results show that a complex spatial network structure is formed after the gelation of the polymer gel system. As the polymer concentration increases, the network structure of the gel system becomes denser. At the same time, the unit network structure is becoming smaller, and the order of the grid chain structure becomes clearer. Under the condition of low polymer concentrations, the backbone structures of the gel are obvious, but there are a lot of fine pores. When the polymer concentration is greater than 1,500 mg/L and the injection rate is less than 0.15 ml/min, the water flooding breakthrough pressure is greater than 0.2 MPa, the plugging rate is greater than 95%, and a good plugging effect is obtained.

In the article, we employed and extended the chemo-mechanical model for a hollow spherical particle to account for different optimization strategies for improved battery performance. In particular, we assessed the influence of surface tension and coating on a hollow particle. We have shown that hollow spherical particles can significantly reduce the charging time with only a small sacrifice of the theoretical capacity. Surface tension, however, plays as negligible role in the hollow as in a solid spherical particle, when the particle is synthesized at micro-level. Finally, we assess the influence of the coating on the hollow particle and found that it can effectively push the whole active particle into compressive state.