High-performance Lithium-ion Battery Anodes Research Articles

CoO nanocrystals dispersed in N-doped carbon networks as enhanced anode for lithium storage

CoO emerges as a promising anode material for lithium-ion batteries (LIBs) because of high theoretical specific capacity and rich resource. However, its practical application is impeded by significant volume expansion and poor electrical conductivity during the charging and discharging cycles. Herein, we construct a nanocomposite of CoO nanocrystals and N-doped carbon serving as an enhanced anode for LIBs by a facile strategy. In the nanocomposite, CoO nanocrystals with average size of 60 nm uniformly were dispersed in N-doped carbon networks. The synergy effects of CoO nanocrystals and N-doped carbon networks can extremely enhance electronic conductivity, relieve volume expansion, and effectively protect CoO nanocrystals from aggregating. Hence, the composite anode delivers large reversible capacity (1190 mAh g−1 at 0.3 A g−1 after 100 cycles), remarkable rate capability (592 mAh g−1 at 5 A g−1), and long cycling ability. This offers a simple approach for designing high-performance anodes for LIBs.

Co(OH)2 derived from in-situ conversion of metal Co confined within a spongy porous carbon for high-performance lithium-ion battery anode

Fabricating Co(OH)2/C composites is considered as an efficient solution to poor conductivity and significant volume expansion issues of Co(OH)2 anode during cycle, but the easy conversion of Co(OH)2 into cobalt oxides during thermal treatment process limits structural design of materials and selection of carbon precursors, hence constricting the diversified design and structural optimization of the Co(OH)2/C composites. Herein, a distinctive method is demonstrated to embed Co(OH)2 nanoparticles (NPs) into a porous carbon (PC), which involves in-situ conversion of the metallic Co NPs confined within a spongy PC into Co(OH)2 NPs by simple H2O2 treatment under hydrothermal conditions. The as-prepared composite is referred as Co(OH)2@PC. This method avoids the conversion of Co(OH)2 into cobalt oxides during preparation of Co(OH)2/C. Moreover, the findings verify that the rational combination of porous carbon and nanoscale Co(OH)2 NPs endows Co(OH)2@PC with enhanced conductivity, improved Li+ diffusion coefficient, high capacitive contribution, stable structure and a LiF-rich SEI layer during cycle. As a result, the Co(OH)2@PC exhibits outstanding electrochemical performance, displaying 815.8 and 543.4 mAh g−1 after 120 cycles at 0.2 and 1.0 A g−1, respectively. This work may broaden the way for diversified design and structural optimization of Co(OH)2/C anodes of lithium-ion batteries.

Magnesiothermic reduction SiO coated with vertical carbon layer as high-performance anode for lithium-ion batteries

Silicon monoxide (SiO), as one of the most competitive anode materials for lithium-ion batteries (LIBs), has received considerable attention. Nevertheless, poor initial Coulombic efficiency (ICE) and larger volume change are the main obstacles to the application of SiO. Here, we suggest a controllable route for the modification of micro-sized SiO via magnesiothermic reduction. To prevent the excessive growth of Si grains caused by the overheating reaction, the solid-state thermal reaction between Mg and SiO is achieved by mixing a certain proportion of NaCl at a suitable temperature, resulting in a loose surface and porous structure of SiO particles, which is conducive to the transportation of lithium ions and electrons. Combined with chemical vapor deposition (CVD), the carbon-coated SiOx composites (M-SiOx@C-R, where R is the molar ratio for Mg and SiO) exhibit unique morphology structure and remarkable electrochemical characteristics. As expected, the vertical carbon network improves the conductivity and alleviates the volume expansion of SiOx. Notably, the M-SiOx@C-0.75 electrode offers a large initial specific capacity of 2283.17 mAh g−1 with a higher ICE of 86.03 % at 100 mA g−1. Furthermore, the full cells using M-SiOx@C-0.75 composite as the negative electrode and LiNi0.8Co0.1Mn0.1O2 (NCM811) as the positive electrode were assembled. After 150 cycles, the full cell still delivers a high specific capacity of 72.22 mAh g−1 (with a retention rate of 47 %). This work provides a feasible route for the fabrication of applicable SiO-based anode materials.

Formation of hollow stepped FePBA@rGO anode for high-performance lithium-ion batteries

Prussian blue and its analogues (PBAs) have been considered promising anode materials for lithium-ion batteries (LIBs) owing to their high theoretical capacity and cost-effectiveness. However, they often encounter challenges such as poor electronic conductivity and structural instability. Herein, we introduce a hollow stepped FePBA framework structure coated with reduced graphene oxide (FePBA@rGO). This sophisticated design significantly improves electronic conductivity and optimizes the diffusion pathways for lithium ions, leading to exceptional cycling stability and rate performance. The FePBA@rGO-15 anode developed in this study shows a notable rate capability of 294 mAh g−1 at a current density of 2 A g−1. More significantly, it demonstrates exceptional lithium storage performance, maintaining a capacity of 1245 mAh g−1 after 600 cycles at a current density of 1 A g−1. Density functional theory simulations further support our findings by illustrating that the robust interface between FePBA and rGO significantly accelerates the reactions kinetics of Li+ within the FePBA framework. This study represents a significant advancement towards improving the capacity and cycling stability of PBA-based anode materials, offering promising prospects for future battery applications.

Consecutive covalent bonds reconstruct robust dual-interfaces by carbonized binder to enable conductive-additive-free durable silicon anode

The substantial volume expansion and poor electrical conductivity tremendously hinder the utilization of high silicon (Si) content anode with compelling capacity. Herein, we propose an efficient strategy to stabilize Si-based anodes by carbonization of the slurry-casting Si electrode with a conductive polyoxadiazole (POD) binder. Such POD-derived materials can form a nitrogen/sulfur-rich carbon network, not only serving as a resilient scaffold to buffer the volume swelling and firmly adhere the Si to the current collector by robust dual-interfaces bonding but also evolving into a conductive matrix to facilitate the electron/ion transport. The conductive-additive-free Si electrode possesses a high Si content of up to 84 %. It exhibits a high initial Coulombic efficiency (86.34 %), competitive gravimetric capacity (3340 mAh g−1), stable cycling performance (the capacity retention rate reaches 79 % after 1000 cycles), commercial-level areal capacity (5.32 mAh cm−2), and outstanding rate capability (1673 mAh g−1 at 5.0 A g−1). This work offers a scalable modification idea and forward-looking perspective for high-performance Si-based anodes in next-generation lithium-ion batteries.

Hierarchical mesoporous Co3O4@C-N nanostructure rods derived from a metal-organic framework as high-performance anode for lithium-ion battery

A uniform hierarchical mesoporous Co3O4@C-N nanostructure rods were in situ fabricated successfully by developing a facile one-step strategy. Cobalt-based metal organic framework [Co3(ndc)(HCOO)3(μ-OH)(H2O)]n with special Co chine constructed framework structure treated as a precursor directly pyrolyzed in a mixed atmosphere of argon and oxygen (95:5) at 500 °C for 2 h. According to the XRD pattern, SEM, TEM, EDS mapping images and XPS spectrum analysis, the well-defined hierarchical mesoporous Co3O4@C-N nanostructure rods showed pure Co3O4 phase, are assembled from a large number of core–shell structured Co3O4@C-N spherical particles with an ultrasmall and uniform size (∼8 nm) which were further connected by N doped carbon net to form nanostructure rods. Using as anode material for lithium-ion batteries, these hierarchical mesoporous Co3O4@C-N nanostructure rods exhibit excellent electrochemical performance with high reversible capacity, rate capability and good cycling stability. They maintained a reversible specific capacity of more than 1000 mAh/g at 100 mA/g, and the discharge specific capacities at the 5 current density of 0.1, 0.2, 0.5, 1, 2, and 5 A/g reached 1123, 1094, 1044, 979, 879 and 688 mAh/g, respectively.

MoS2/SnS heterostructure composite for high-performance lithium-ion battery anodes

Layered metal sulfides are potential anode materials for lithium-ion batteries (LIBs) because their unique structure makes them suitable for Li+ de-intercalation. As a typical 2D layered material, MoS2 is a potential anode material for LIBs due to the weak van der Waals forces between the layers, which facilitates the de-intercalation of Li+ and supports multiple Li+. However, when MoS2 is used as anodes for LIBs material, rapid capacity decay hinders the application. Coupling two different materials to form a heterogeneous structure is an effective way to solve the above problems. In this work, one-pot hydrothermal method is proposed to construct MoS2/SnS heterostructure composites. The electrochemical properties are significantly enhanced, which could be attributed to the presence of heterogeneous structures, leading to increase the electrode charge transfer rate and interfacial reaction kinetics. The results show that the discharge capacity of the MoS2/SnS-1.5 electrode is about 1492.1 mAh/g at 500 mA/g. Furthermore, assembled MoS2@SnS-1.5||LiCoO2 full cell displays a high discharge capacity of 226.1 mAh/g after 50 cycles at 500 mA/g. This facile method provides the application value of layered metal sulfides as LIBs anode materials.

Constructing Si@CN@MXene from silicon waste as high-performance lithium-ion battery anodes

Silicon represents one of the most attractive materials for anodes in lithium-ion batteries (LIBs) due to highest theoretical specific capacity. Thus, there is a most urgent need to prepare Si-based nano materials in a very efficient way, and develop some reasonable approaches for their modification in order to resolve the short-falls of Si anode, which include both low conductivity and huge volume changes during intercalation of lithium ions. In this work, the kerf loss silicon (KL Si) from the photovoltaic industry has been used as an inexpensive Si source for the synthesis of the Si@CN@MXene (SCM) composite to be applied as an anode material. Meanwhile, the chitosan works as the charge bridge in sequence with the Si and MXene nanosheets under electrostatic force during composite preparation. The MXene nanosheet and N-doped carbon layer that build up during chitosan calcination can be attributed to forming a hierarchical high-speed conductive network over the surface of silicon, which contributed to alleviate the volume expansion of silicon. The SCM electrode discharge capacity was obtained at a stable value of 900.8 mAh g−1 at 0.5 A g−1, 861.9 mA g−1 at 1 A g−1 and 657.6 mA g−1 even at 2 A g−1 after 100 cycles. The SCM electrode also exhibited good rate performance from 0.2 to 5 A g−1. Therefore, this study recommends that the method is very promising for producing the silicon anode material for LIBs from KL Si.

One-step fabrication of binder-free nanoSi-CNT-carbon black/cyclized PAN composite anode for high-performance lithium-ion batteries

Silicon is one of the most promising anode materials for lithium-ion batteries (LIBs) due to its high theoretical capacity. However, its non-conductive nature and significant volume expansion during lithiation pose challenges. In this study, we developed a novel electrode comprising silicon nanoparticles (nanoSi), carbon nanotubes (CNTs), and carbon black (CB) in cyclized polyacrylonitrile (cPAN), referred to as nanoSi-CNT-CB/cPAN. This electrode is fabricated through a one-step thermal process by heating a cast nanoSi-CNT-CB/PAN film on Cu foil at 310 °C. The LIB performance using the nanoSi-CNT-CB/cPAN electrode shows an impressive initial coulombic efficiency of 93.1 % at 0.1 A g−1, a high specific capacity of 2267.2 mAh g−1 at 0.5 A g−1, and a retention of 89.2 % over 390 cycles, achieving 783 mAh g−1 at 5 A g−1. We attribute these results to the fused cPAN, which provides good adhesion to nanoSi, CNTs, CB, and Cu foil, acting as a binder, active material, and ionic conductive medium. The well-dispersed CNTs and CB form an effective conductive network in the electrode. Additionally, the one-step electrode fabrication is a simple and cost-effective process for next-generation Si-based LIBs.

A Novel Gelatin Binder with Helical Crosslinked Network for High-Performance Si Anodes in Lithium-Ion Batteries.

Silicon(Si) is a promising anode material for lithium-ion batteries, but its large volume expansion during cycling poses a challenge for the binder design. In this study, a novel gelatin binder is designed and prepared with a helical crosslinked network structure. This gelatin binder is prepared by enzymatic crosslinking and immersion in Hofmeister salt solution, which induces the formation of network and helical secondary structures. The helical crosslinked network structure can be analogous to a spring group system to effectively dissipate the stress and strain caused by the Si expansion. The gelatin binder is further partially carbonized by low-temperature pyrolysis, which improves its conductivity and stability. The Sianode with the optimized gelatin binder exhibits high initial coulombic efficiency, excellent rate performance, and long-term cycling stability. This study provides an innovative approach for the preparation of high-performance Si anodes, namely by controlling the molecular configuration of the binder to significantly improve the cycle stability, which can also be applied to other high-capacity anode materials that suffer from large volume changes during cycling.

ZIF-derived "cocoon"-like in-situ Zn/N-doped carbon as high-capacity anodes for Li/Na-ion batteries

Owing to the unique structure and physicochemical properties, including high specific surface area, self-doped N atoms, open pore structure and good chemical stability, zeolitic imidazolate frameworks (ZIFs) and their derivatives have been widely used in the field of energy storage. Here, a new type of "cocoon"-like Zn/N doped ZIF-derived porous carbon (Zn@N-C-800) is synthesized as an anode for lithium-ion batteries (LIBs) and sodium ion batteries (SIBs) through a one-step carbonization process using a novel Zn-ZIF as the precursor. In Zn@N-C-800, the "cocoon"-like disordered carbon skeleton is conducive to electrolyte infiltration, while the Zn/N doping can provide additional active sites for ion storage. Benefiting from these unique structural characteristics, Zn@N-C-800 achieves excellent electrochemical performances as anode for both LIBs and SIBs: an ultrahigh rate capability of 352 mAh g−1 can be delivered at 12.8 A g−1 for LIBs; an outstanding long-term cycling stability (312 mAh g−1 at 1 A g−1 after 2000 cycles) can be achieved for SIBs. This paper provides new ideas for the design and preparation of high-performance anodes for LIBs and SIBs.

Co-Assembly of Polyoxometalates and Porphyrins as Anode for High-Performance Lithium-Ion Batteries.

Polyoxometalates (POMs) have been considered one of the most promising anode candidates for lithium-ion batteries (LIBs) in virtue of their high theoretical capacity and reversible multielectron redox properties. However, the poor intrinsic electronic conductivity, low specific surface area, and high solubility in organic electrolytes hinder their widespread applications in LIBs. Herein, a novel hybrid nanomaterial is synthesized by co-assembling POMs and porphyrins (PMo12/CoTPyP) through a facile solvothermal method. The POM clusters are stabilized by porphyrin units through electrostatic interactions, which simultaneously realize the uniform dispersion of POMs and porphyrin units. Benefiting from the generated sub-1nm channels for fast ion transport and the synergistic effect between evenly distributed PMo12 clusters and high-conductive CoTPyP units, the LIB based on the optimized PMo12/CoTPyP anode exhibits significantly improved Li+ storage capability as well as superior rate and cycling performance. The results of density functional theory simulations further reveal that the co-assembly of PMo12 and CoTPyP can accelerate the mobility of Li+ and electrons, which in turn promotes the enhancement of LIBs performance. This work paves a strategy for synthesizing POMs-based anode materials with simultaneously high dispersibility, redox activity, and stability.

A novel embedded KVO3/NC anode for high-performance lithium-ion batteries

Vanadium-based metallic salts, characterized by their intrinsic low electronic conductivity, are impeding their advancement as anode materials in the realm of lithium-ion battery technology. This study presents a novel embedded anode material KVO3/NC (KVO/NC) synthesized via a sol–gel method, with KVO3 (KVO) particles in situ growing on N-doped carbon, thereby ameliorating conductivity and electrochemical performance. The findings reveal that KVO/NC composite has three lithium-ion storage sites, ultra-high cycling stability (289 mA h/g@5000 cycles@10 C@100 %), and superior rate performance (249 mA h/g@15 C; 221 mA h/g@20 C). Coupled with LiFePO4 cathode, it achieves a competitive energy density (391 W h kg−1@0.1 C; 1–3.9 V). This work reveals the practical potential of KVO/NC as a new type of lithium-ion battery anode material with high energy density and long cycle life through a series of ex situ/in situ characterizations.

Insight into graphene/boron arsenide heterostructure used for high-performance lithium-ion battery anode materials: The first principles study

Two-dimensional (2D) van der Waals (vdW) heterostructures demonstrate potential applications in Lithium-ion batteries (LIBs) characterized by their elevated energy storage capacity and extended operational longevity as anode materials. The structures and electronic properties of graphene/boron arsenide (Gr/BAs) heterostructures, along with the adsorption and migration of lithium (Li) atoms within the structures, are methodically analyzed through first-principles studies underpinned by density functional theory. Our calculations indicate the metallic Gr/BAs heterostructures have the structural stability, where their mechanical strength is confirmed from the elastic constant. Its diffusion barrier of Li atoms (0.25 eV) is superior among similar anode materials. The Li atoms' diffusion coefficient within the Gr/BAs heterostructure at 300 K (1.27 × 10−10 m2/s) exceeds that observed in Gr (2.0×10−11 m2/s). Besides, the presence of Gr assists in maintaining the open-circuit voltage (OCV) of Gr/BAs heterostructures in the range of 0-1 V. The theoretical specific capacity of proposed heterostructure reaches 920 mAh/g. The present calculations suggest that the Gr/BAs heterostructure could serve effectively as an anode in LIBs due to its excellent electrical conductivity, small diffusion barriers and appropriate open-circuit voltage.

Modulating porous silicon-carbon anode stability: Carbon/silicon carbide semipermeable layer mitigates silicon-fluorine reaction and enhances lithium-ion transport

Silicon-based material is regarded as one of the most promising anodes for next-generation high-performance lithium-ion batteries (LIBs) due to its high theoretical capacity and low cost. Harnessing silicon carbide's robustness, we designed a novel porous silicon with a sandwich structure of carbon/silicon carbide/Ag-modified porous silicon (Ag-PSi@SiC@C). Different from the conventional SiC interface characterized by a frail connection, a robust dual covalent bond configuration, dependent on SiC and SiOC, has been successfully established. Moreover, the innovative sandwich structure effectively reduces detrimental side reactions on the surface, eases volume expansion, and bolsters the structural integrity of the silicon anode. The incorporation of silver nanoparticles contributes to an improvement in overall electron transport capacity and enhances the kinetics of the overall reaction. Consequently, the Ag-PSi@SiC@C electrode, benefiting from the aforementioned advantages, demonstrates a notably elevated lithium-ion mobility (2.4 * 10−9 cm2·s−1), surpassing that of silicon (5.1 * 10−12 cm2·s−1). The half-cell featuring Ag-PSi@SiC@C as the anode demonstrated robust rate cycling stability at 2.0 A/g, maintaining a capacity of 1321.7 mAh/g, and after 200 cycles, it retained 962.6 mAh/g. Additionally, the full-cell, featuring an Ag-PSi@SiC@C anode and a LiFePO4 (LFP) cathode, exhibits outstanding longevity. Hence, the proposed approach has the potential to unearth novel avenues for the extended exploration of high-performance silicon-carbon anodes for LIBs.

Tailoring nanoscale primary silicon in laser powder bed fusion for high-performance lithium-ion battery anodes

Silicon-based anodes, utilizing nanosized silicon materials, hold great promise for the next-generation of lithium-ion batteries due to their high capacity and stable expansion. This study aims to address challenges in traditional slurry-coated anodes, such as agglomeration and low adhesive strength, through the application of laser powder bed fusion (LPBF). The process involves fabricating an Al-Si-Cu alloy layer on a Cu foil current collector, followed by dealloying to create a porous Si-Cu anode. Simulated and experimental results demonstrate successful alloy layer formation through optimized laser spot (55 μm) and powder sizes (1–5 μm). Controlled cooling produces primary Si particles ranging from 150 nm to 1 μm. The resulting microstructure enhances electrochemical performance, particularly by tailoring the size of primary Si. The resultant porous Si-Cu anode, featuring uniformly distributed primary Si (200 nm) metallurgically bonded with Cu networks, exhibits an initial coulombic efficiency of 83% and a remarkable capacity retention of 80% after 300 cycles at 2 C. In-situ and ex-situ observations confirm the crucial role of anode architecture in performance enhancement. This study elucidates the influence of the LPBF microstructure on anode performance and broadens the potential application of laser powder bed fusion in battery manufacturing.

Novel binary regulated silicon-carbon materials as high-performance anodes for lithium-ion batteries

The massive volume dilation, unsteady solid electrolyte interphase, and weak conductivity about Si have failed to bring it to practical applications, although its potential capacity is up to 4200 mAh g−1. For solving these problems, novel binary regulated silicon–carbon materials (Si/BPC) were done by a sol–gel procedure combined with single carbonization. Analytical techniques were systematically utilized to examine the effects of element doping at several gradients on morphology, structure and electrochemical properties of composites, thus the optimal content was identified. Si/BPC preserves a discharge specific capacity of 1021.6 mAh g−1 with a coulomb efficiency of 99.27% after 180 cycles at 1000 mA g−1, within the upgrade than single-doped and undoped. In rate test, it has a specific capacity of 1003.2 mAh g−1 at a high current density of 5000 mA g−1, quickly back towards 2838.6 mAh g−1 at 200 mA g−1. The inclusion of B and P elements is linked to the electrochemical characteristics. In the co-doped carbon layers, the synergistic impact of doping B and P accelerates the diffusion kinetics of lithium ions, boosts diffusion rate of Li+, offers low electrochemical impedance (45.75 Ω). This brings more defects to provide transport carriers and induces a substantial amount of electrochemically active sites, which fosters the storage of Li+, thus making silicon material electrochemically more active and potential.

Regeneration of photovoltaic industry silicon waste toward high-performance lithium-ion battery anode

Regeneration of photovoltaic industry silicon waste toward high-performance lithium-ion battery anode

Facile synthesis of SiOx/C as high-performance anodes for lithium-ion batteries

Despite its high capacity (∼2615 mAh·g−1), silicon oxide (SiOx) suffers from low electrical conductivity and volume expansion during cycling, leading to capacity fading. In this work, a SiOx/C composite was synthesized by magnesium thermal reduction using co-assembled mesoporous SiO2 and graphitic carbon nitride (g-C3N4) as precursors. The SiOx/C composite displays a sheet-like nanostructure with highly dispersed SiOx. The presence of carbon enhances the conductivity and structural stability of the composite, leading to a low charge resistance (94.0 Ω), fast lithium diffusion (DLi+ = 5.15 × 10−14 cm2·s−1), and excellent cycling capability (863 mAh·g−1 after 160 cycles).

Construction of sub micro-nano-structured silicon based anode for lithium-ion batteries

The significant volume change experienced by silicon (Si) anodes during lithiation/delithiation cycles often triggers mechanical-electrochemical failures, undermining their utility in high-energy-density lithium-ion batteries (LIBs). Herein, we propose a sub micro-nano-structured Si based material to address the persistent challenge of mechanic-electrochemical coupling issue during cycling. The mesoporous Si-based composite submicrospheres (M-Si/SiO2/CS) with a high Si/SiO2 content of 84.6 wt.% is prepared by magnesiothermic reduction of mesoporous SiO2 submicrospheres followed by carbon coating process. M-Si/SiO2/CS anode can maintain a high specific capacity of 740 mAh g−1 at 0.5 A g−1 after 100 cycles with a lower electrode thickness swelling rate of 63%, and exhibits a good long-term cycling stability of 570 mAh g−1 at 1 A g−1 after 250 cycles. This remarkable Li-storage performance can be attributed to the synergistic effects of the hierarchical structure and SiO2 frameworks. The spherical structure mitigates stress/strain caused by the lithiation/delithiation, while the internal mesopores provide buffer space for Si expansion and obviously shorten the diffusion path for electrolyte/ions. Additionally, the amorphous SiO2 matrix not only servers as support for structure stability, but also facilitates the rapid formation of a stable solid electrolyte interphase layer. This unique architecture offers a potential model for designing high-performance Si-based anode for LIBs.