In this paper, we conduct a comprehensive investigation on the thermal transport in one-dimensional (1D) van der Waals (vdW) heterostructures by using non-equilibrium molecular dynamics simulations. ...As for the considered 1D vdW heterostructures having a base of (40,40) carbon nanotube (CNT), we find that the boron nitride nanotube (BNNT) coating can increase the thermal conductance of inner CNT base by 36%, while the molybdenum disulfide nanotube (MSNT) coating can reduce the thermal conductance by 47%. The different effects of nanotube coatings on the thermal transport behaviors of 1D vdW heterostructures are explained by the competition mechanism between the improved heat flux and the increased temperature gradient in 1D vdW heterostructures. The thermal transport in 1D vdW heterostructures containing three layers is also investigated. It is found that the coaxial BNNT-MSNT coating can significantly reduce the thermal conductance of inner CNT base by 61%, which is even larger than the influence of an individual MSNT coating. This work not only provides molecular insights into the heat transport behaviors of 1D vdW heterostructures but also provides guidance for the design of 1D vdW heterostructures with desired thermal properties.
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The rapid development of battery technology has promoted the deployment of electric vehicles (EVs). To ensure the healthy and sustainable development of EVs, it is urgent to solve the problems of ...battery safety monitoring, residual value assessment, and predictive maintenance, which heavily depends on the accurate state-of-health (SOH) estimation of batteries. However, many published methods are unsuitable for actual vehicle conditions. To this end, a data-driven method based on the random partial charging process and sparse Gaussian process regression (GPR) is proposed in this article. First, the random capacity increment sequences ( △Q ) at different voltage segments are extracted from the partial charging process. The average value and standard deviation of △Q are used as features to indicate battery health. Second, correlation analysis is conducted for three types of batteries, and high correlations between the features and battery SOH are verified at different temperatures and discharging current rates. Third, by using the proposed features as inputs, sparse GPR models are constructed to estimate the SOH. Compared with other data-driven methods, the sparse GPR has the highest estimation accuracy, and its average maximum absolute errors are only 2.88%, 2.52%, and 1.51% for three different types of batteries, respectively.
Graphullerene (GF), an extended quasi-two-dimensional network of C60 molecules, is proposed as a multicontact platform for constructing superlubric interfaces with layered materials. Such interfaces ...are predicted to present very small and comparable sliding energy corrugation regardless of the identity of the underlying flat layered material surface. It is shown that, beyond the geometrical effect, covalent interlinking between the C60 molecules results in reduction of the sliding energy barrier. For extended GF supercells, negligible sliding energy barriers are found along all sliding directions considered, even when compared to the case of the robust superlubric graphene/h-BN heterojunction. This suggests that multicontact architectures can be used to design ultrasuperlubric interfaces, where superlubricity may persist under extreme sliding conditions.Graphullerene (GF), an extended quasi-two-dimensional network of C60 molecules, is proposed as a multicontact platform for constructing superlubric interfaces with layered materials. Such interfaces are predicted to present very small and comparable sliding energy corrugation regardless of the identity of the underlying flat layered material surface. It is shown that, beyond the geometrical effect, covalent interlinking between the C60 molecules results in reduction of the sliding energy barrier. For extended GF supercells, negligible sliding energy barriers are found along all sliding directions considered, even when compared to the case of the robust superlubric graphene/h-BN heterojunction. This suggests that multicontact architectures can be used to design ultrasuperlubric interfaces, where superlubricity may persist under extreme sliding conditions.
