Anode Material For Secondary Batteries Research Articles

SiOx/C Composite Anode for Lithium-Ion Battery with Improved Performance Using Graphene Quantum Dots and Carbon Nanoparticles.

In this study, a composite was manufactured by mixing graphene quantum dots, silicon oxide, and carbon nanoparticles, and the characteristics of the anode materials for secondary batteries were examined. To improve the capacity of the graphene quantum dot (GQD) anode material, the added silicon oxide content was varied among 0, 5, 10, 15, and 30 wt%, and carbon nanoparticles were added as a structural stabilizer to alleviate silicon oxide volume expansion. The physical properties of the prepared GQD/SiOx/C composite were investigated through XRD, SEM, EDS, and powder resistance analysis. Additionally, the electrochemical properties of the manufactured composite were observed through an analysis of the charge-discharge cycle, rate, and impedance of a lithium secondary battery. In the GQD/SiOx/C composite, by adding carbon nanoparticles, an internal cavity was formed that can alleviate the volume expansion of silicon oxide, and the carbon nanoparticles and silicon oxide particles were uniformly distributed. The formed internal cavity had a silicon oxide content of 5 wt%. Low initial efficiency was observed, and above 30 wt%, low cycle stability was observed. The GQD/SiOx/C composite with 15 wt% of silicon oxide added showed an initial discharge capacity of 595 mAh/g, a capacity retention rate of 92%, and a rate characteristic of 81 at 2 C/0.1 C. Silicon oxide was added to improve the capacity of the anode material, and carbon nanoparticles were added as a structural stabilizer to buffer the volume change of the silicon oxide. To use GQD/SiOx/C composite as a highly efficient anode material, the optimal silicon oxide content and carbon nanoparticle mechanism as a structural stabilizer were discussed.

Challenges and Prospects of Phosphorus‐based Anode Materials for Secondary Batteries

AbstractThe research of new electrode materials is vital, among which anode materials have a significant role in the improvement of the overall energy density of batteries. Phosphorus‐based anode materials show tremendous potential in the exploration of anode materials due to their high theoretical capacity, natural abundance, and environmental friendliness. In this review, we sum up the latest research progress of red phosphorus‐based, black phosphorus‐based, and transition metal phosphide‐based anode materials for lithium‐ion batteries (LIBs) and sodium‐ion batteries (SIBs). The features of the phosphorus‐based materials, the preparation methods, and the advantages/disadvantages are introduced, as well as the electrochemical storage mechanism of LIBs and SIBs. On this basis, the problems of phosphorus‐based anode materials are considered and analyzed in depth and improvement strategies are proposed. Finally, the directions that phosphorus‐based materials will take in the future are examined. This paper is intended to advance knowledge of phosphorus‐based anode materials among researchers and to offer some recommendations for using such materials in LIBs and SIBs.

Tailored chemically bonded metal phosphide@carbon nanowire arrays on foam metal as an all-in-one anode for ultrahigh-area-capacity sodium-ion batteries

Metal phosphides are superior anode materials for secondary batteries but suffer from variable volume and low electronic conductivity. In this work, chemically bonded metal phosphide@carbon nanowire arrays with adjustable structure mounted on foam metal were synthesized via a general facile chemical vapor deposition (CVD)-like approach using an environmentally friendly, solid ionic resin as a phosphorus source. The diameter of the nanowires and thicknesses of the carbon shell could be tailored via control of the synthesis conditions. Using a Fe2P@C array on iron foam as an example, it was demonstrated that the new materials could be used directly as an electrode in sodium-ion batteries (SIBs) without any additives or post-processing. The Fe2P@C electrode delivered a significantly high area capacity of 0.40 mAh cm−2 after 1400 cycles at a current density of 3 mA cm−2, a capacity retention rate of 80.25 %, which is, to the best of our knowledge, one of the most stable, high surface capacity performances achieved in SIBs at this large current density. Tests showed that the Fe2P@C nanowire array on a 3D foam structure provided a larger exposure area for electrolyte penetration, a shorter passage for Na+ diffusion, and faster electronic transfer. In situ TEM revealed that the carbon shell effectively alleviated volume expansion of the Fe2P and in-situ Raman and XRD verified the mechanism and high reversibility of Fe2P@C.

Carbon Nanotube Interwoven Polyhedrons with Inside-out Lithiophilic Gradients toward Stable Lithium Metal Battery

Lithium metal is one of the most potential anode materials for secondary batteries with high energy density. Nevertheless, the uncontrolled dendrite growth, fragile solid electrolyte interphase and theoretical infinite volume expansion during repeated plating/stripping process cause low Coulombic efficiency, short cycle life, and safety hazard. Carbon nanotube interwoven polyhedrons evolved from ZIF-8@ZIF-67 core–shell framework with inside-out lithiophilic gradients are prepared for lithium metal accommodation. The well-designed architecture with decreasing gradient of the main lithiophilic content ZnO from the inside out enables dendrite-free lithium deposition and stripping, and the outer interwoven carbon nanotubes induced by Co nanoparticles provide an optimal path to guide the diffusion of Li ion reduction from inside to outside as well as excellent electron conduction network for the whole anode. As the lithium metal host, the average Coulombic efficiency of lithium metal batteries can reach up to 98.2% (200 cycles) at 1 mA cm−2, and an extended lifespan (1500 h) is achieved at 3 mA cm−2. As was expected, outstanding capacity retention (82.7% after 300 cycles) with a competitive high-mass-loading (18.3 mg cm−2) LiFePO4 cathode at 1 C is realized. This structure design concept expands a promising application pathway of abundant carbon-based materials in lithium metal batteries.

Heterogeneous interface containing selenium vacancies space-confined in double carbon to induce superior electronic/ionic transport dynamics for sodium/potassium-ion half/full batteries

The exploration of suitable anode materials to overcome key issues of electrode volume fluctuation and sluggish electronic/ionic transport dynamics caused by the large radius of sodium/potassium ions is an urgent need for Na+/K+ storage. Herein, a fascinating FeSe2/CoSe2/C (FCSe@C) containing heterostructure and special selenium vacancies is confined within the void space inside carbon sphere by using a combination strategy of melting diffusion and selenization. Surface chemical states and structural analyses demonstrate that the as-obtained FCSe@C@void@C is constructed by an internal FCSe@C core and an external carbon sphere. The rational design of double carbon architectures with large interior void space can not only promote the electrical conductivity but also protect the integrity of selenide during cycling. As a result, FCSe@C@void@C electrode delivers the prominent energy storage properties in half/full SIBs and PIBs. More importantly, the thorough understanding of heterogeneous interfaces on the improved performance is explicitly interpreted by combining experimental and theoretical analysis. This work demonstrates a new idea to construct phase interface and internal reserved void structure of transition metal selenides, and provide an effective method for the design and optimization of other advanced anode materials for secondary batteries and other energy storage systems.

Turning waste into treasure: Reuse of contaminant-laden adsorbents (Cr(vi)-Fe3O4/C) as anodes with high potassium-storage capacity

In this study, we try to find possible solutions to synchronously solving energy and environmental problems. In our design, orange peel is used as a carbon source to synthesize low-cost Fe3O4/C composites, which are employed as adsorbents to purify Cr(vi)-contaminated water. After that, these Cr(vi)-laden Fe3O4/C composites are used and tested as anodes in potassium-ion batteries. It is found that their K-storage capacity is more than 300 mAh g−1 at a current density of 0.1 A g−1, depending on the mass content of Fe3O4. The more Fe3O4 component in composite, the more adsorbed Cr(vi) species through chemisorption, and the larger K-storage capacity. The good electrical conductivity of cabon-based anodes endows them with superior rate performance. At current densities of 0.1, 0.5, 1 and 2 A g−1, K-storage capacity amounts to 357.8, 316.3, 276.3 and 236.8 mAh g−1, respectively. The reuse of contaminant-laden adsorbents as anodes will shed new light on the disposal of exhausted adsorbents after water treatment and development of anode materials for secondary batteries.

Morphological Effect on Electrochemical Properties of BaSnO₃ as an Anode Material for Lithium Ion Batteries.

In this study, we investigated the electrochemical effects of morphological changes using BaSnO₃ (BSO) of various shapes (columns, hollow rods, spheres) as anode materials for Li-ion batteries. The BSOs were prepared by hydrothermal method and their electrochemical properties were evaluated using galvanostataic charge/discharge and CV test. As a results, columnar BSO exhibits the best electrochemical properties, as an inert material, BaO can contribute to Li storage because of higher electrical conductivity. This results suggest that the formation of column shape can lead to improved electrochemical properties as anode materials of secondary battery.

Novel approach for controlling free-carbon domain in silicone oil-derived silicon oxycarbide (SiOC) as an anode material in secondary batteries

Silicon oxycarbide (SiOC) has been regarded as potential anode for lithium-ion secondary batteries (LIBs) due to high reversible capacities (higher than conventional graphite) and superior electrical conductivity with regard to free-carbon domain (FCD). Thus, controlling and optimizing the FCD in SiOC is essential factor in determining battery performance. In this study, the FCD controlled SiOC is successfully synthesized via a simple pyrolysis using silicone oil and phenyl group-containing additives (divinylbenzene (DVB)) as precursors. The DVB is critical for the incorporation of carbon to facilitate Si-O-C bonding as well as the formation of the FCD in SiOC. The SiOC anode materials show that there is a dependence between the FCD content and electrochemical performance. The FCD controlled SiOC exhibits remarkable electrochemical performance as compared to carbon-excess materials, such as high reversible capacity (550 mAh g−1 at 200 mA g−1), cycle stability (95% capacity retention after 200th cycles at 200 mA g−1) and superior rate capability (300 mAh g−1 at 2000 mA g−1).

High-Performance Ionic Liquid Gel Polymer Electrolytes for Solid-State Lithium Metal Batteries

Lithium metal is considered as a “Holy Grail” anode material for secondary batteries because of its extremely high theoretical specific capacity (3860 mA h g−1), low electrochemical potential (-3.04 V vs. SHE), and low density (0.59 g cm-3). Ionically conductive polymer electrolytes represent a class of environmental-friendly and inflammable electrolytes for solid-state batteries that can enable the use of lithium metal. In our study, we fabricated lithium metal batteries based on transparent self-standing ionic liquid gel polymer electrolytes (ILGPEs) and LiFePO4cathodes. We evaluated the properties of ILGPEs by engineering the compositional space between the constituting components: poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP), N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide (PP13TFSI), and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). The ionic conductivity of ILGPE increases with the increase of PP13TFSI and LiTFSI, and a maxima conductivity was obtained when the mass ratio of PP13TFSI, PVDF-HFP, and LiTFSI was 3:1:1, and the value was 1.3 mS cm-1at 22 ºC, and then increased to 5.82 mS cm-1at 80 °C. The optimized ILGPE showed excellent compatibility with lithium metal, determined by the interfacial resistance stability with the elapsed time. The solid-state LiFePO4cells delivered a practical capacity approaching 89.5% of the theoretical capacity and a capacity retention of 95.1% after 200 cycles with a current density of C/5 at 22 ºC. The solid-state lithium metal batteries using various cathodes materials, such as NMC, Co-free layered oxides, disordered rocksalt were also evaluated.

Synthesis of Rice Ball Shaped Rare Earth-Carbon Composite Electrode Material for Lithium-Ion Batteries

The CeO2, known as one of the typical rare earth oxides, is seen to have considerable potential for being used as novel anode materials for secondary batteries because it shows excellent electrochemical redox properties. When it is considered as an anode material, the foremost advantages are that its volumetric and morphological changes are hardly observed, so it could provide good stability and longevity of secondary batteries. It is well explained by the fully reversible phase transformation between fluorite structured CeO2 and cubic structured Ce2O3 during the electrochemical reaction. Nonetheless, it is essential to improve the conductivity problem of the CeO2 which has intrinsically low electron conductivity in order to apply it to secondary batteries. Meanwhile, there used to be a widely used method called carbon composite method to support nonconductive metal oxides. In this study, we have synthesized the CeO2-Carbon composite sphere in the form of rice balls to improve the conductivity problems of the rare earth oxide during their electrochemical performance. A rice ball structure is expected to provide more advanced electronic conductive networks than a core shell structure does. Indeed, high stability was observed during the charging and discharging process of LIB due to the nanostructures in the form of rice balls.

Ultrathin Bismuth Nanosheets for Stable Na-Ion Batteries: Clarification of Structure and Phase Transition by in Situ Observation.

Bismuth has garnered tremendous interest for Na-ion batteries (NIBs) due to potentially high volumetric capacity. Yet, the bismuth upon sodiation/desodiation experiencing structure and phase transitions remains unclear, which sets a challenge for accessing nanotechnology and nanofabrication to achieve its applicability. Here, we use in situ transmission electron microscopy to disclose the structure and phase transitions of layered bismuth (few-layer bismuth nanosheets) during Na+ intercalation and alloying processes. Multistep phase transitions from Bi → NaBi → c-Na3Bi (cubic) → h-Na3Bi (hexagonal) are clearly identified, during which the Na+ migration from interlayer to in-plane evokes the structure transition from ABCABC stacking type of c-Na3Bi to ABABAB stacking type of h-Na3Bi. It is found that the metastable c-Na3Bi devotes to buffer the dramatic structure changes from thermodynamic stable h-Na3Bi, which unveils the origin of volume expansion for bismuth and has important consequences for 2D in-plane structure. As the lateral ductility can efficiently alleviate the in-plane mechanical strain caused by the Na+ migration, the few-layer bismuth nanosheet exhibits a potential cyclability for NIBs. Our findings will encourage more attention to bismuthene as a novel anode material for secondary batteries.

Electrodeposition of Pure Phase Snsb As Anode Material for Lithium- and Sodium- Ion Batteries

Commercial industries currently utilize graphite as the primary lithium anode material for secondary batteries. Graphite’s gravimetric capacity, however, has already been fully utilized and materials with higher capacities are more desirable for the advancement of next generation applications, such as electric vehicles. Of these materials, intermetallic alloys such as SnSb are of interest due to their ability to store multiple alkali metals per metal center, resulting in higher gravimetric and volumetric capacities. Electrodeposition is a promising method to produce these alloy anodes, as it can control the particle morphology, size, thickness, composition, and is easily scalable to larger productions. In this work, we have successfully synthesized pure SnSb by electrodeposition which, based on the authors’ knowledge, is the first occurrence to date. The synthesis is carefully analyzed through tools and techniques such as cyclic voltammetry, scanning electron microscopy, and x-ray diffraction. Electrochemical testing of the electrodeposited SnSb samples showed promising performance of the material, with long cycle life and high rate capabilities as both lithium- and sodium- ion battery anodes. It is also found that purity of the material has an evident impact on the electrochemical performance of the electrode, in which control of the purity is important to the material’s cycling lifetime.

Stabilization of Lithium Metal Anodes by Hybrid Artificial Solid Electrolyte Interphase

Li metal is among the most attractive anode materials for secondary batteries, with a theoretical specific capacity > 3800 mAh g–1. However, its extremely low electrochemical potential is associated with high chemical reactivity that results in undesirable reduction of electrolyte species on the lithium surface, leading to spontaneous formation of a solid electrolyte interphase (SEI) with uncontrolled composition, morphology, and physicochemical properties. Here, we demonstrate a new approach to stabilize Li metal anodes using a hybrid organic/inorganic artificial solid electrolyte interphase (ASEI) deposited directly on the Li metal surface by self-healing electrochemical polymerization (EP) and atomic layer deposition (ALD). This hybrid protection layer is thin, flexible, ionically conductive, and electrically insulating. We show that Li metal protected by the hybrid protection layer gives rise to very stable cycling performance for over 300 cycles at current density 1 mA/cm2 and over 110 cycles at current density 2 mA/cm2, well above the threshold for dendrite growth at unprotected Li. Our strategy for protecting Li metal anodes by hybrid organic/inorganic ASEI represents a new approach to mitigating or eliminating dendrite formation at reactive metal anodes—illustrated here for Li—and may expedite the realization of a “beyond-Li-ion” battery technology employing Li metal anodes (e.g., Li–S).

Preparation of silicon nanoball encapsulated with graphene shell by CVD and electroless plating process

Abstract Carbon materials such as graphite have been widely used as the anode materials of secondary batteries. In spite of good stability, they are limited by low capacity. Silicon has a 4 times higher capacity than any other carbon material. But it cannot be used, because it has a low stability caused by the volume expansion. In this study, we fabricated a silicon nanoball encapsulated with graphene (Si-GB) to overcome the mentioned problems. In order to form a core/shell structured graphene encapsulated silicon nanoball, nickel was coated on the surface of a silicon nanoball by electroless plating method. Then, a graphene layer was synthesized on the surface of the nickel shell by a CVD process. We were able to make a Si-GB by etching the nickel layer. The Si-GBs were formed with a spherical void between the silicon particle and the graphene layer, by which it has a better safety against to volumetric change of anode during lithiation/delitiation of repeated charging–discharging in secondary batteries. Morphology of the graphene encapsulated silicon nanoball was observed by the field emission scanning electron microscope (FESEM) and the field emission transmission electron microscope (FETEM) to find core–shell structured nanoball. Spherical structure of graphene encapsulated silicon nanoball was investigated by the Raman, the X-ray Photoelectron Spectroscopy to identify graphene layer on the surface of the inner silicon core. The charge–discharge performance of the Li-ion battery using Si-GB was investigated by the battery cycler system.

ChemInform Abstract: Recent Progress of Silicon Composites as Anode Materials for Secondary Batteries

AbstractReview: 117 refs.

Silicon Non-Metal Compounds As New Promising Materials for Lithium Ion Batteries

Due to an increasing energy demand caused by an expanding global population and the rapid development of new technologies, a high priority to a further development of new battery systems is given. In fact, there is a great interest in Lithium Ion Batteries as they offer a high energy density and a high rate capability [1]. Owing to a high theoretical capacity silicon is a promising anode material to replace commercially used graphite [2]. The electrochemical energy storage originates from an alloying-dealloying mechanism where different lithium-silicon phases like Li12Si7, Li15Si4 or Li22Si5 were formed [2]. This mechanism conducts capacity fading caused by volume expansion during the insertion and extraction of lithium ions. Therefore, nanostructured silicon is expected to meet future criteria defined for new electrochemical energy storage systems. A new promising way to produce silicon nanoparticles is the application of silicon non-metal compounds and their decomposition through an electrochemical in situ conversion mechanism. In addition, the non-metal serves as a Li-containing matrix that buffers the volume expansion during charging and discharging. Moreover, the synthesis of silicon non-metal compounds via planetary ball mill is environmentally benign and easy scalable. Initial studies show that phase-pure produced silicon diphosphide (SiP2) is electrochemical active over a wide potential range. The first discharge cycle reaches a capacity closely to theory (about 3100 mAh/g). Continuous cycling is stable about 100 cycles. Cyclic voltammetry experiments give an insight into the behavior of the redox properties of materials which is in this case very similar compared to pure silicon. From this observation a similar reaction of silicon diphosphide as known from silicon is indicated. Ex situ XRD results confirm the proposed reaction mechanism and refers to the formation of lithium phosphide which serves as buffering matrix. The production of smaller particles is challenging and the large capacity fading after the first cycle needs to be explained and to be overcome. Both points are taken as prospective tasks. [1] C.-M. Park, J.-H. Kim, H. Kim, H.-J. Sohn: Li-alloy based anode materials for secondary batteries. In: Chem. Soc. Rev. VI. 39, 2010, S. 3115–3141. [2] S. Goriparti, E. Miele, F. De Angelis, E. De Fabrizio, R. P. Zaccaria, C. Capiglia: Review on recent progress of nanostructured anode materials for Li-ion batteries. In: J. Power Sources VI. 257, 2014, S. 421–443.

Preparation of Graphene Encapsulated Silicon Nanoball.

Concerning application of graphene, a lot of efforts have been made to improve performance of nanomaterials in many fields, such as electric and electronic devices. Some examples are preparation of 3-dimension structured nanomaterials like nanoballs by CVD process and hybridizing with silicon. These graphene-based materials are proven to be available for secondary battery, EMI and ACF in electronics. Especially, some research has shown that they were very effective to enhance safety and volumetric capacity when they were used as anode materials of secondary battery. Although graphite and its compound with metal have been used as an anode material due to their high stability and reversibility, it still has lower charge capacity. On the contrary, silicon is known as a material which increases the charge capacity up to four times, compared with carbon-based materials, but it has lower stability and reversibility. For that reason, a few researchers just started to improve the charge capacity by hybridization of carbon-based material with silicon. In this paper, we prepared nanocarbon based material which has a new structure of graphene encapsulated silicon nanoball as an anode material which is applicable to high-capacity secondary battery. In order to form a graphene encapsulated silicon nanoballs, the polystyrene encapsulated silicon nanoballs were prepared by emulsion polymerization of styrene monomer with silicon nanoparticles. The resulting nanoballs were immersed in iron chloride solution and then dried. Finally they were treated in high temperature through CVD and etched by hydrogen chloride. Morphology of the graphene encapsulated silicon nanoballs was observed by the field emission scanning electron microscope (FESEM) and the field emission transmission electron microscope (FETEM) to search for core-shell structured nanoball. Spherical structure of graphene encapsulated silicon nanoball was investigated by the Raman, the X-ray Photoelectron Spectroscopy to identify graphene layers on the surface of the inner silicon core.

Phosphorus-Based Composite Anode Materials for Secondary Batteries

Phosphorus-Based Composite Anode Materials for Secondary Batteries

Recent progress of silicon composites as anode materials for secondary batteries

This review mainly focuses on the latest research achievements of Si composites and their nanostructures as anode materials in lithium-ion batteries. The most recent applications of Si to sodium-ion and magnesium-ion batteries are also included.

96/04922 Manufacture of carbonaceous materials for secondary battery anodes

96/04922 Manufacture of carbonaceous materials for secondary battery anodes