Flexible Lithium-ion Battery Anodes Research Articles

PVD synthesis of binder-free silicon and carbon coated 3D α-Fe2O3 nanorods hybrid films as high-capacity and long-life anode for flexible lithium-ion batteries

Flexible lithium-ion batteries are being given great attention as up-and-coming power source for the development of flexible and wearable electronic devices. In this work, a carbon and silicon coated 3D α-Fe2O3 nanorod arrays on carbon cloth composite was firstly designed by facile hydrothermal method and physical vapor deposition process. The as-prepared composite can be directly applied as flexible anode for Li-ion batteries without adding any binder and conducting materials. The electrochemical results show that the composite exhibits outstanding electrochemical lithium storage properties with high initial Coulombic Efficiency of 76% at 100 mA g−1 current density and a superior cycling performance that could maintain about 910 mAh·g−1 after 500 cycles at a 500 mA g−1 current density, which is two to three times of commercial graphite anodes. This study offers a promising route to greatly enhance the electrochemical properties of metal oxides and provides suggestive insights for developing high-performance electrode materials for flexible energy storage devices.

Novel carbon coated core-shell heterostructure NiCo2O4@NiO grown on carbon cloth as flexible lithium-ion battery anodes

Binding-free NiCo2O4@NiO@C/cc electrode was prepared by hydrothermal method, annealing method and physical vapor deposition. In this composite, NiCo2O4@NiO was strongly grown on carbon cloth and formed a core-shell heterostructure, which can facilitate the transport of ions. What's more, the conductivity was dramatically improved after coating NiO nanofalkes. Additionally, carbon coating can inhibit volume expansion, improve material conductivity and structural stability. The free-standing electrode material showed an initial capacity of 1885 mAh g−1 at a current density of 100 mA g−1, after 100 cycles, the reversible capacity stabilized around 1051 mAh g−1 with Coulomb efficiency of 99.9%. At a high rate of 1600 mA g−1, the capacity exhibited about 721 mAh g−1, indicating that the NiCo2O4@NiO@C/cc composite is an outstanding material as the anode electrode material for flexible lithium-ion batteries with broad application prospect.

Flexible Graphene‐Wrapped Carbon Nanotube/Graphene@MnO2 3D Multilevel Porous Film for High‐Performance Lithium‐Ion Batteries

The ingenious design of a freestanding flexible electrode brings the possibility for power sources in emerging wearable electronic devices. Here, reduced graphene oxide (rGO) wraps carbon nanotubes (CNTs) and rGO tightly surrounded by MnO2 nanosheets, forming a 3D multilevel porous conductive structure via vacuum freeze-drying. The sandwich-like architecture possesses multiple functions as a flexible anode for lithium-ion batteries. Micrometer-sized pores among the continuously waved rGO layers could extraordinarily improve ion diffusion. Nano-sized pores among the MnO2 nanosheets and CNT/rGO@MnO2 particles could provide vast accessible active sites and alleviate volume change. The tight connection between MnO2 and carbon skeleton could facilitate electron transportation and enhance structural stability. Due to the special structure, the rGO-wrapped CNT/rGO@MnO2 porous film as an anode shows a high capacity, excellent rate performance, and superior cycling stability (1344.2 mAh g-1 over 630 cycles at 2 A g-1 , 608.5 mAh g-1 over 1000 cycles at 7.5 A g-1 ). Furthermore, the evolutions of microstructure and chemical valence occurring inside the electrode after cycling are investigated to illuminate the structural superiority for energy storage. The excellent electrochemical performance of this freestanding flexible electrode makes it an attractive candidate for practical application in flexible energy storage.

Fabrication of Si Nanoparticles@Carbon Fibers Composites from Natural Nanoclay as an Advanced Lithium-Ion Battery Flexible Anode

In this paper, a cost-effective strategy for fabricating silicon-carbon composites was designed to further improve the electrochemical performance and commercialization prospects of Si anodes for lithium-ion batteries (LIBs). Silicon-carbon fibers (CFs) were prepared by loading Si nanoparticles (SiNPs) on interconnected carbon fibers via an electrospinning technique (SiNPs@CFs). The Si nanoparticles were obtained by the reduction reaction of natural clay minerals. As a flexible anode for LIBs, the SiNPs@CFs anode demonstrated a reversible capacity of 1238.1 mAh·g−1 and a capacity retention of 77% after 300 cycles (in contrast to the second cycle) at a current density of 0.5 A·g−1. With a higher current density of 5.0 A·g−1, the electrode showed a specific capacity of 528.3 mAh·g−1 after 1000 cycles and exhibited a superior rate capability compared to Si nanoparticles. The excellent electrochemical properties were attributed to the construction of flexible electrodes and the composite comprising carbon fibers, which lessened the volume expansion and improved the conductivity of the system.

Porous CoS nanosheets coated by N and S doped carbon shell on graphene foams for free-standing and flexible lithium ion battery anodes: Influence of void spaces, shell and porous nanosheet

The mass production of the sixth generation flexible cell phone screen is boosting the demand for flexible lithium ion batteries with high energy density and longer lifetime. CoS with high theoretical capacity and graphene foams with excellent flexibility can be candidates. In this work, CoS nanosheets are synthesized by electrodeposition and sulfuration. For the first time, free-standing porous CoS nanosheets supported on graphene foams with N and S doped carbon shells are synthesized by carbonization and sulfuration of polydopamine, which enhances conductivity. With controllable precursors, three types of morphologies were obtained and the influences of void spaces, carbon shells and the inner pores are studied. The void space and porous structure of CoS nanosheets can benefit the lithium ion diffusion and rate capability while the void space and conformal carbon shells can improve the stability of electrodes and long cycling performances. By combining the advantages of void spaces, shells and porous nanosheet structures, a high cyclic capacity of 481.7 mA h g-1 is delivered, evaluated by the overall weight of the electrode at 0.1C (1C = 600 mA h g-1) after 100 cycles and good rate capability.

Hierarchical Fe2O3@CNF fabric decorated with MoS2 nanosheets as a robust anode for flexible lithium-ion batteries exhibiting ultrahigh areal capacity

Hierarchical Fe2O3@CNF@MoS2 fabric film was fabricated as robust anode for flexible LIBs exhibiting ultrahigh areal capacity.

Enhanced reversible lithium ion storage in stable 1T@2H WS2 nanosheet arrays anchored on carbon fiber

Recent years, as a competitive anode material for lithium ion batteries (LIBs), tungsten disulfide (WS2) has attracted significant attention for its high theoretical capacity, abundant resources and low cost, but how to improve the cycle stability and reversible capacity is still an important research subject. In this work, stable metallic WS2 anchored on carbon fiber cloth was fabricated as flexible anode for LIBs. The transversal displacement of S atoms in WS2 was induced by incorporation of N atoms, and the stability of metallic phase WS2 was ensured by the formation of N-W covalent bonds. The results of electrochemical measurement and dynamics analysis demonstrate that the incorporation of metallic phase could not only reduce the initial discharge capacity loss, but also improve the reversible capacity than traditional semi-conducting phase WS2.

Hierarchical carbon cloth supported Li4Ti5O12@NiCo2O4 branched nanowire arrays as novel anode for flexible lithium-ion batteries

Abstract The hierarchical carbon cloth supported Li 4 Ti 5 O 12 @NiCo 2 O 4 branched nanowire (NW) arrays were fabricated as the flexible, binder-free anode for lithium-ion batteries. The novel composite exhibits greatly improved specific capacity and rate capability as well as excellent cyclic stability compared to carbon cloth supported Li 4 Ti 5 O 12 NW arrays. The results clearly demonstrate that branched growth of NiCo 2 O 4 NWs on the surface of Li 4 Ti 5 O 12 NWs on carbon cloth enhances lithium diffusion. The superior electrochemical performance is ascribed to the unique architecture as well as the synergetic effect of good flexibility and high conductivity of carbon cloth, almost zero volume change during charge/discharge process of Li 4 Ti 5 O 12 , and high capacity and conductivity of NiCo 2 O 4 . This novel anode possesses high potential for applications in high-performance, flexible lithium-ion batteries.

Improved cycling stability of MoS2-coated carbon nanotubes on graphene foam as flexible anodes for lithium-ion batteries

Flexible binder-free MoS2-coated carbon nanotubes on graphene foam have been produced and this novel composite exhibited enhanced electrochemical behavior.

Mn3O4/nitrogen-doped porous carbon fiber hybrids involving multiple covalent interactions and open voids as flexible anodes for lithium-ion batteries

Flexible Mn3O4/NPCF hybrids with a reasonable microstructure and multiple interactions delivered a high capacity of 1058 mA h g−1.

Fe7Se8@C core–shell nanoparticles encapsulated within a three-dimensional graphene composite as a high-performance flexible anode for lithium-ion batteries

The composite Fe7Se8@C encapsulated within 3D-graphene serves as a high-performance flexible anode for LIBs with excellent rate performance.

Zn2GeO4 nanorods grown on carbon cloth as high performance flexible lithium-ion battery anodes

A novel strategy was proposed for the simultaneous preparation of a high performance flexible Zn2GeO4/CC electrode. The as-formed composites exhibited high reversible lithium storage capacity, long cyclability, and excellent rate capability.

Microwave synthesis of SnS2 nanoflakes anchored graphene foam for flexible lithium-ion battery anodes with long cycling life

SnS2 nanoflakes anchored three dimensional graphene foam (SnS2@GF) as flexible lithium ion battery anodes were fabricated via a single mode microwave hydrothermal technique. The flexible SnS2@GF electrode shows high capacity, high rate capability and long cycling life for lithium ion battery. The SnS2@GF electrode exhibits a high reversible specific capacity 1386.7mAh/g at 0.1A/g and a long cycling life with a high capacity of 818.4mAh/g after 500 cycles at 1A/g. The excellent performance of flexible SnS2@GF electrode is attributed to the reduced strain during intercalation/extraction process, shortened ion transport distance, higher conductivity and more electrode/electrolyte contact area.

Three-dimensional SnO2@TiO2 double-shell nanotubes on carbon cloth as a flexible anode for lithium-ion batteries

In this study, three-dimensional SnO2@TiO2 double-shell nanotubes on carbon cloth are synthesized by a combination of the hydrothermal method for ZnO nanorods and a subsequent SnO2 and TiO2 thin film coating with atomic layer deposition (ALD). The as-prepared SnO2@TiO2 double-shell nanotubes are further tested as a flexible anode for Li ion batteries. The SnO2@TiO2 double-shell nanotubes/carbon cloth electrode exhibited a high initial discharge capacity (e.g. 778.8 mA h g−1 at a high current density of 780 mA g−1) and good cycling performance, which could be attributed to the 3D double-layer nanotube structure. The interior space of the stable TiO2 hollow tube can accommodate the large internal stress caused by volume expansion of SnO2 and protect SnO2 from pulverization and exfoliation.

Self-assembly silicon/porous reduced graphene oxide composite film as a binder-free and flexible anode for lithium-ion batteries

A Si/porous reduced graphene oxide (rGO) composite film synthesized by evaporation and leavening method are developed as a high-performance anode material for lithium ion batteries. The porous structure as buffer base can effectively release the volume expansion of the silicon particles, increase the electrical conductivity and reduce the transfer resistance of Li ions. The Si/porous rGO composite film presents high specific capacity and good cycling stability (1261mAhg−1 at 50mAg−1 up to 70 cycles), as well as enhanced rate capability. This approach to prepare such a unique structure is a low-cost and facile route for the silicon-based anode materials.

Three-dimensional hierarchical MoS2nanoflake array/carbon cloth as high-performance flexible lithium-ion battery anodes

3D hierarchical MoS2nanoflake array/carbon cloth is synthesized with a thickness of MoS2nanoflakes <15 nm. A full Li battery based on the cloth exhibits good electrochemical performance and high flexibility.