Self-adaptive strain-relaxation optimization for high-energy lithium storage material through crumpling of graphene

Abstract

High-energy lithium battery materials based on conversion/alloying reactions have tremendous potential applications in new generation energy storage devices. However, these applications are limited by inherent large volume variations and sluggish kinetics. Here we report a self-adaptive strain-relaxed electrode through crumpling of graphene to serve as high-stretchy protective shells on metal framework, to overcome these limitations. The graphene sheets are self-assembled and deeply crumpled into pinecone-like structure through a contraction-strain-driven crumpling method. The as-prepared electrode exhibits high specific capacity (2,165 mAh g À 1 ), fast charge-discharge rate (20 A g À 1 ) with no capacity fading in 1,000 cycles. This kind of crumpled graphene has self-adaptive behaviour of spontaneous unfolding-folding synchronized with cyclic expansion-contraction volumetric variation of core materials, which can release strain and maintain good electric contact simultaneously. It is expected that such findings will facilitate the applications of crumpled graphene and the self-adaptive materials.

Three-dimensional-networked NiCo2S4 nanosheet array/carbon cloth anodes for high-performance lithium-ion batteries

“…16,17 Recently, direct growth of self-supported NiCo 2 O 4 nanowires and ZnCo 2 O 4 nanowire arrays on current-collecting substrates has been shown to overcome the drawbacks of mixing active electrode materials with conductive additives and binders and to increase endurance of fast charge and discharge processes. 22,23 Furthermore, it has been reported that 3D network structures (for example, graphene networks, 7 MO/3D graphene network composites 24 and diamond/ carbon nanotubes 25 ) can provide open channels for efficient electron/ ion transport and large surface area for reactions, both of which are favorable properties for materials and devices used in electrochemical applications. In this work, we report the synthesis of 3D-networked NiCo 2 S 4 nanosheet arrays (NSAs) directly on carbon cloth and their application as an anode material in LIBs; to our knowledge, this is the first such demonstration.…”

“…1-3 The increasing applications of LIBs in daily electronic devices-along with industry demands for further improvement in energy density, durability, rate capability and safety-have driven the development of new electrode materials and new electrode structures. [4][5][6][7] Among the great variety of anode materials studied, metal oxides (MOs) and metal sulfides ( 21 have been synthesized and offer superior electrochemical energy storage capacity compared with bulk MSs. However, the large volumetric change of MS nanostructures during electrochemical reactions leads to reduced capacity and poor cycling stability.…”

“…[1][2][3] The increasing applications of LIBs in daily electronic devices-along with industry demands for further improvement in energy density, durability, rate capability and safety-have driven the development of new electrode materials and new electrode structures. [4][5][6][7] Among the great variety of anode materials studied, metal oxides (MOs) and metal sulfides (MSs) such as Co 3 2 15 comprise an important class of materials that can be charged and discharged through redox reactions. Compared with their MO counterparts, MSs generally feature higher electrical conductivity, better mechanical and thermal stability, and richer redox chemistry, making them attractive anode materials for high-performance LIBs.…”

Microscale characterization of coupled degradation mechanism of graded materials in lithium batteries of electric vehicles

“…The interference beam can be decomposed into S and P components to decide the direction of movement. Film is made of high strength alloy steel and the contact surface with test piece is flat and strictly parallel [75,[145][146][147][148][149]. Stress wave propagates forward in the input film with test piece placed between input and output films [150][151][152][153][154][155].…”

Electromagnetic effects model and design of energy systems for lithium batteries with gradient structure in sustainable energy electric vehicles

“…Lithium batteries with this electromagnetic gradient structure have shown prospects in electric vehicles and large-scale battery packs [57], although a number of issues need to be solved at the scientific level to achieve the necessary performance levels. As previously stated, the research on lithium battery with tailored electromagnetic structure originated from the negative impact of thermal stress on the battery [58,59]. So far a number of ideas and research methods play an important role in systems design and microstructural characterization, including as homogenization and multifunctional integrated design.…”