Controlled Nitrogen Doping in Crumpled Graphene for Improved Alkali Metal-Ion Storage under Low-Temperature Conditions

The significant performance decay in conventional graphite anodes under low-temperature conditions is attributed to the slow diffusion of alkali metal ions, requiring new strategies to enhance the charge storage kinetics at low temperatures. Here, nitrogen (N)-doped defective crumpled graphene (NCG) is employed as a promising anode to enable stable low-temperature operation of alkali metal-ion storage by exploiting the surface-controlled charge storage mechanisms. At a low temperature of −40 °C, the NCG anodes maintain high capacities of ≈172 mAh g⁻¹ for lithium (Li)-ion, ≈107 mAh g⁻¹ for sodium (Na)-ion, and ≈118 mAh g⁻¹ for potassium (K)-ion at 0.01 A g⁻¹ with outstanding rate-capability and cycling stability. A combination of density functional theory (DFT) and electrochemical analysis further reveals the role of the N-functional groups and defect sites in improving the utilization of the surface-controlled charge storage mechanisms. In addition, the full cell with the NCG anode and a LiFePO₄ cathode shows a high capacity of ≈73 mAh g⁻¹ at 0.5 °C even at −40 °C. The results highlight the importance of utilizing the surface-controlled charge storage mechanisms with controlled defect structures and functional groups on the carbon surface to improve the charge storage performance of alkali metal-ion under low-temperature conditions.     

Sodium Storage Behavior in Natural Graphite using Ether‐based Electrolyte Systems

This work reports that natural graphite is capable of Na insertion and extraction with a remarkable reversibility using ether‐based electrolytes. Natural graphite (the most well‐known anode material for Li–ion batteries) has been barely studied as a suitable anode for Na rechargeable batteries due to the lack of Na intercalation capability. Herein, graphite is not only capable of Na intercalation but also exhibits outstanding performance as an anode for Na ion batteries. The graphite anode delivers a reversible capacity of ≈150 mAh g^?1 with a cycle stability for 2500 cycles, and more than 75 mAh g^?1 at 10 A g^?1 despite its micrometer‐size (≈100 μm). An Na storage mechanism in graphite, where Na⁺‐solvent co‐intercalation occurs combined with partial pseudocapacitive behaviors, is revealed in detail. It is demonstrated that the electrolyte solvent species significantly affect the electrochemical properties, not only rate capability but also redox potential. The feasibility of graphite in a Na full cell is also confirmed in conjunction with the Na_1.5VPO_4.8F_0.7 cathode, delivering an energy of ≈120 Wh kg^?1 while maintaining ≈70% of the initial capacity after 250 cycles. This exceptional behavior of natural graphite promises new avenues for the development of cost‐effective and reliable Na ion batteries.     

Reconstruction of Conformal Nanoscale MnO on Graphene as a High‐Capacity and Long‐Life Anode Material for Lithium Ion Batteries

To tackle the issue of inferior cycle stability and rate capability for MnO anode materials in lithium ion batteries, a facile strategy is explored to prepare a hybrid material consisting of MnO nanocrystals grown on conductive graphene nanosheets. The prepared MnO/graphene hybrid anode exhibits a reversible capacity as high as 2014.1 mAh g^?1 after 150 discharge/charge cycles at 200 mA g^?1, excellent rate capability (625.8 mAh g^?1 at 3000 mA g^?1), and superior cyclability (843.3 mAh g^?1 even after 400 discharge/charge cycles at 2000 mA g^?1 with only 0.01% capacity loss per cycle). The results suggest that the reconstruction of the MnO/graphene electrodes is intrinsic due to conversion reactions. A long‐term stable nanoarchitecture of graphene‐supported ultrafine manganese oxide nanoparticles is formed upon cycling, which yields a long‐life anode material for lithium ion batteries. The lithiation and delithiation behavior suggests that the further oxidation of Mn(II ) to Mn(IV ) and the interfacial lithium storage upon cycling contribute to the enhanced specific capacity. The excellent rate capability benefits from the presence of conductive graphene and a short transportation length for both lithium ions and electrons. Moreover, the as‐formed hybrid nanostructure of MnO on graphene may help achieve faster kinetics of conversion reactions.     

Ultrathin Layered Hydroxide Cobalt Acetate Nanoplates Face‐to‐Face Anchored to Graphene Nanosheets for High‐Efficiency Lithium Storage

The dramatically increasing demand of high‐energy lithium‐ion batteries (LIBs) urgently requires advanced substitution for graphite‐based anodes. Herein, inspired from the extra capacity of lithium storage in solid‐electrolyte interface (SEI) films, layered hydroxide cobalt acetates (LHCA, Co(Ac)_0.48(OH)_1.52·0.55H₂O) are introduced as novel and high‐efficiency anode materials. Furthermore, ultrathin LHCA nanoplates are face‐to‐face anchored on the surface of graphene nanosheets (GNS) through a facile solvothermal method to improve the electronic transport and avoid agglomeration during repeated cycles. Profiting from the parallel structure, LHCA//GNS nanosheets exhibit extraordinary long‐term and high‐rate performance. At the current densities of 1000 and 4000 mA g^?1, the reversible capacities maintain ≈1050 mAh g^?1 after 200 cycles and ≈780 mAh g^?1 after 300 cycles, respectively, much higher than the theoretical value of LHCA according to the conversion mechanism. Fourier transform infrared spectroscopy confirms the conversion from acetate to acetaldehyde after lithiation. A reasonable mechanism is proposed to elucidate the lithium storage behaviors referring to the electrocatalytic conversion of OH groups with Co nanocatalysts. This work can help further understand the contribution of SEI components (especially LiOH and LiAc) to lithium storage. It is envisaged that layered transition metal hydroxides can be used as advanced materials for energy storage devices.     

Nitrogen‐Doped Graphene Ribbon Assembled Core–Sheath MnO@Graphene Scrolls as Hierarchically Ordered 3D Porous Electrodes for Fast and Durable Lithium Storage

Graphene scroll is an emerging 1D tubular form of graphitic carbon that has potential applications in electrochemical energy storage. However, it still remains a challenge to composite graphene scrolls with other nanomaterials for building advanced electrode configuration with fast and durable lithium storage properties. Here, a transition‐metal‐oxide‐based hierarchically ordered 3D porous electrode is designed based on assembling 1D core–sheath MnO@N‐doped graphene scrolls with 2D N‐doped graphene ribbons. In the resulting architecture, porous MnO nanowires confined in tubular graphene scrolls are mechanically isolated but electronically well‐connected, while the interwoven graphene ribbons offer continuous conductive paths for electron transfer in all directions. Moreover, the elastic graphene scrolls together with enough internal voids are able to accommodate the volume expansion of the enclosed MnO. Because of these merits, the as‐built electrode manifests ultrahigh rate capability (349 mAh g^?1 at 8.0 A g^?1; 205 mAh g^?1 at 15.0 A g^?1) and robust cycling stability (812 mAh g^?1 remaining after 1000 cycles at 2.0 A g^?1) and is the most efficient MnO‐based anode ever reported for lithium‐ion batteries. This unique multidimensional and hierarchically ordered structure design is believed to hold great potential in generalizable synthesis of graphene scrolls composited with oxide nanowires for mutifuctional energy storage.     

Lithium Accommodation in a Redox‐Active Covalent Triazine Framework for High Areal Capacity and Fast‐Charging Lithium‐Ion Batteries

The synthesis of a new type of redox‐active covalent triazine framework (rCTF) material, which is promising as an anode for Li‐ion batteries, is reported. After activation, it has a capacity up to ≈1190 mAh g^?1 at 0.5C with a current density of 300 mA g^?1 and a high cycling stability of over 1000 discharge/charge cycles with a stable Coulombic efficiency in an rCTF/Li half‐cell. This rCTF has a high rate performance, and at a charging rate of 20C with a current density of 12 A g^?1 and it functions well for over 1000 discharge/charge cycles with a reversible capacity of over 500 mAh g^?1. By electrochemical analysis and theoretical calculations, it is found that its lithium‐storage mechanism involves multi‐electron redox‐reactions at anthraquinone, triazine, and benzene rings by the accommodation of Li. The structural features and progressively increased structural disorder of the rCTF increase the kinetics of infiltration and significantly shortens the activation period, yielding fast‐charging Li‐ion half and full cells even at a high capacity loading.     

A New Strategy to Build a High‐Performance P′2‐Type Cathode Material through Titanium Doping for Sodium‐Ion Batteries

Herein, Ti⁴⁺ in P′2‐Na_0.67[(Mn_0.78Fe_0.22)_0.9Ti_0.1]O₂ is proposed as a new strategy for optimization of Mn‐based cathode materials for sodium‐ion batteries, which enables a single phase reaction during de‐/sodiation. The approach is to utilize the stronger Ti–O bond in the transition metal layers that can suppress the movements of Mn–O and Fe–O by sharing the oxygen with Ti by the sequence of Mn–O–Ti–O–Fe. It delivers a discharge capacity of ≈180 mAh g^?1 over 200 cycles (86% retention), with S‐shaped smooth charge–discharge curves associated with a small volume change during cycling. The single phase reaction with a small volume change is further confirmed by operando synchrotron X‐ray diffraction. The low activation barrier energy of ≈541 meV for Na⁺ diffusion is predicted using first‐principles calculations. As a result, Na_0.67[(Mn_0.78Fe_0.22)_0.9Ti_0.1]O₂ can deliver a high reversible capacity of ≈153 mAh g^?1 even at 5C (1.3 A g^?1), which corresponds to ≈85% of the capacity at 0.1C (26 mA g^?1). The nature of the sodium storage mechanism governing the ultrahigh electrode performance in a full cell with a hard carbon anode is elucidated, revealing the excellent cyclability and good retention (≈80%) for 500 cycles (111 mAh g^?1) at 5C (1.3 A g^?1).     

Densified Metallic MoS2/Graphene Enabling Fast Potassium‐Ion Storage with Superior Gravimetric and Volumetric Capacities

The potassium‐ion battery (PIB) is an attractive energy storage device that possesses the potential advantages of high energy density and low cost. Herein, a pure 1T‐MoS₂ is synthesized on graphene oxide and assembled into a hydrogel. The hydrogel is further tightened to a compact 1T‐MoS₂/graphene (CTMG) bulk by a densifying strategy of capillary tension. When employed as an anode for PIBs, the CTMG electrode can store K⁺ through reversible intercalation and conversion electrochemistry, accompanied with fast kinetics since the 1T‐MoS₂ induces a pseudocapacitive storage mechanism and the extraordinary K⁺ transportation ability. Consequently, the CTMG electrode delivers the high and reversible rate capacities of 511 and 327 mAh g^‐1 at 0.1 and 1 A g^‐1, respectively. Moreover, the compact architecture reduces the electrode thickness by ≈33% enabling a high volumetric capacity (512 mAh cm^‐3 at 0.1 A g^‐1 after 100 cycles), as well as holding a promising application in thick electrode.     

Few‐Layered SnS2 on Few‐Layered Reduced Graphene Oxide as Na‐Ion Battery Anode with Ultralong Cycle Life and Superior Rate Capability

Na‐ion Batteries have been considered as promising alternatives to Li‐ion batteries due to the natural abundance of sodium resources. Searching for high‐performance anode materials currently becomes a hot topic and also a great challenge for developing Na‐ion batteries. In this work, a novel hybrid anode is synthesized consisting of ultrafine, few‐layered SnS₂ anchored on few‐layered reduced graphene oxide (rGO) by a facile solvothermal route. The SnS₂/rGO hybrid exhibits a high capacity, ultralong cycle life, and superior rate capability. The hybrid can deliver a high charge capacity of 649 mAh g^?1 at 100 mA g^?1. At 800 mA g^?1 (1.8 C), it can yield an initial charge capacity of 469 mAh g^?1, which can be maintained at 89% and 61%, respectively, after 400 and 1000 cycles. The hybrid can also sustain a current density up to 12.8 A g^?1 (≈28 C) where the charge process can be completed in only 1.3 min while still delivering a charge capacity of 337 mAh g^?1. The fast and stable Na‐storage ability of SnS₂/rGO makes it a promising anode for Na‐ion batteries.     

Electrocatalysis of Fe-N-C Bonds Driving Reliable Interphase and Fast Kinetics for Phosphorus Anode in Sodium-Ion Batteries

Phosphorus exhibits high capacity and low redox potential, making it a promising anode material for future sodium-ion batteries. However, its practical applications are confined by poor durability and sluggish kinetics. Herein, an innovative in-situ electrochemically self-driven strategy is presented to embed phosphorus nanocrystal (≈10 nm) into a Fe-N-C-rich 3D carbon framework (P/Fe-N-C). This strategy enables rapid and high-capacity sodium ion storage. Through a combination of experimental assistance and theoretical calculations, a novel synergistic catalytic mechanism of Fe-N-C is reasonably proposed. In detail, the electrochemical formation of Fe-N-C catalytic sites facilitates the release of fluorine in ester-based electrolyte, inducing Na⁺-conducting-enhanced solid-electrolyte interphase. Furthermore, it also effectively induces the dissociation energy of the P-P bond and promotes the reaction kinetics of P anode. As a result, the unconventional P/Fe-N-C anode demonstrates outstanding rate-capability (267 mAh g⁻¹ at 100 A g⁻¹) and cycling stability (72%, 10 000 cycles). Notably, the assembled pouch cell achieves high-energy density of 220 Wh kg⁻¹.     

Laser-Manufactured Metastable Supranano SnOx for Efficient Electron/Ion Bridging in SnO2-Graphene Heterostructure Boosting Lithium Storage

Robust anchoring of high-capacity nanocrystals (NCs) on porous conductive substrates is of paramount importance but it is challenging for highly efficient energy storage to prevent the weak interfacial interactions, inevitable aggregation, and sluggish charge transfer, due to the technical hurdles of constructing heterostructures with firm electron/ion bridging. Herein, a facile and high-efficiency liquid-phase laser manufacturing strategy to guarantee the covalent bonding of ultrafine NCs on conductive substrates by predesigning metastable supranano (<10 nm) particles is proposed. The manufacturing of supranano SnO₂ (≈3.4 nm) is demonstrated to tightly anchor on mesoporous walls of graphene with high loading (≈81.3%) and homogenous dispersion. Such a optimized heterostructure with unimpeded electron/ion transfer delivers extraordinary long-term cycling stability (1132 mAh g^–1 at 1.0 A g^–1 after 1250 cycles) and impressive rate capability (275 mAh g^–1 at 30.0 A g^–1) as the anode for Li-storage, which are some of the highest values among the reported SnO₂-based anodes. The study provides an important avenue for addressing the interfacial bridging in-between heterostructures via creating active metastable supranano particles for intriguing electrochemical applications or even beyond, based on laser-matter interactions.     

Electrochemical Intercalation of Potassium into Graphite

Exceptional cycling performance of graphite anode in K‐ion batteries is demonstrated with a reversible capacity of 246 mAh g^–1 and 89% retention of the initial capacity after 200 cycles. Although the graphite anode experiences huge volume change and worse kinetics during K intercalation/deintercalation, the cycling stability delivered in K‐ion batteries is comparable to that of Li‐ion batteries using the same graphite anode. The combination of excellent electrochemical performance, the abundance and wide availability of K in earth's crust, and the well‐developed technology of the graphite anode make the K‐ion battery very attractive for offering a low cost battery chemistry for large‐scale energy storage applications.     

Face‐to‐Face Contact and Open‐Void Coinvolved Si/C Nanohybrids Lithium‐Ion Battery Anodes with Extremely Long Cycle Life

To develop high‐performance anode materials of lithium‐ion batteries (LIBs) instead of commercial graphite for practical applications, herein, a layer of silicon has been well‐anchored onto a 3D graphene/carbon nanotube (CNT) aerogels (CAs) framework with face‐to‐face contact and balanced open void by a simple chemical vapor deposition strategy. The engineered contact interface between CAs and Si creates high‐efficiency channels for the rapid electrons and lithium ions transport, and meanwhile, the balanced open‐void allows the free expansion of Si during cycling while maintaining high structural integrity due to the robust mechanical strength of 3D CAs framework. As a consequence, the as‐synthesized Si/CAs nanohybrids are highly stable anode materials for LIBs with a high reversible discharge capacity (1498 mAh g^?1 at 200 mA g^?1) and excellent rate capability (462 mAh g^?1 at 10 000 mA g^?1), which is much better than Si/graphene‐CNTs‐mixture (51 mAh g^?1 at 10 000 mA g^?1). More significantly, it is found that the Si/CAs nanohybrids display no obvious capacity decline even after 2000 cycles at a high current density of 10 000 mA g^?1. The present Si/CAs nanohybrids are one of the most stable Si‐based anode materials ever reported for LIBs to date.     

Temperature‐Mediated Engineering of Graphdiyne Framework Enabling High‐Performance Potassium Storage

Graphdiyne (GDY), an emerging type of carbon allotropes, possesses fascinating electrical, chemical, and mechanical properties to readily spark energy applications in the realm of Li‐ion and Na‐ion batteries. Nevertheless, rational design of GDY architectures targeting advanced K‐ion storage has rarely been reported to date. Herein, the first example of synthesizing GDY frameworks in a scalable fashion to realize superb potassium storage for high‐performance K‐ion battery (KIB) anodes is showcased. To begin with, first principles calculations provide theoretical guidances for analyzing the intrinsic potassium storage capability of GDY. Meanwhile, the specific capacity is predicted to be as high as 620 mAh g^?1, which is considerably augmented as compared with graphite (278 mAh g^?1). Experimental tests then reveal that prepared GDY framework indeed harvests excellent electrochemical performance as a KIB anode, achieving high specific capacity (≈505 mAh g^?1 at 50 mA g^?1), outstanding rate performance (150 mAh g^?1 at 5000 mA g^?1) and favorable cycling stability (a high capacity retention of over 90% after 2000 cycles at 1000 mA g^?1). Furthermore, kinetic analysis reveals that capacitive effect mainly accounts for the K‐ion storage, with operando Raman spectroscopy/ex situ X‐ray photoelectron spectroscopy identifying good electrochemical reversibility of GDY.     

Phosphorus and Oxygen Dual-Doped Porous Carbon Spheres with Enhanced Reaction Kinetics as Anode Materials for High-Performance Potassium-Ion Hybrid Capacitors

Hard carbons with low cost and high specific capacity hold great potential as anode materials for potassium-based energy storage. However, their sluggish reaction kinetics and inevitable volume expansion degrade their electrochemical performance. Through rational nanostructure design and a heteroatom doping strategy, herein, the synthesis of phosphorus/oxygen dual-doped porous carbon spheres is reported, which possess expanded interlayer distances, abundant redox active sites, and oxygen-rich defects. The as-developed battery-type anode material shows high discharge capacity (401 mAh g⁻¹ at 0.1 A g⁻¹), outstanding rate capability, and ultralong cycling stability (89.8% after 10 000 cycles). In situ Raman spectroscopy and density functional theory calculations further confirm that the formation of P C and P O/P OH bonds not only improves structural stability, but also contributes to a rapid surface-controlled potassium adsorption process. As a proof of concept, a potassium-ion hybrid capacitor is assembled by a dual-doped porous carbon sphere anode and an activated carbon cathode. It shows superior electrochemical performance, which opens a new avenue to innovative potassium-based energy storage technology.     

Electrical Conductivity Adjustment for Interface Capacitive-Like Storage in Sodium-Ion Battery

Sodium-ion battery (SIB) is significant for grid-scale energy storage. However, a large radius of Na ions raises the difficulties of ion intercalation, hindering the electrochemical performance during fast charge/discharge. Conventional strategies to promote rate performance focus on the optimization of ion diffusion. Improving interface capacitive-like storage by tuning the electrical conductivity of electrodes is also expected to combine the features of the high energy density of batteries and the high power density of capacitors. Inspired by this concept, an oxide-metal sandwich 3D-ordered macroporous architecture (3DOM) stands out as a superior anode candidate for high-rate SIBs. Taking Ni-TiO₂ sandwich 3DOM as a proof-of-concept, anatase TiO₂ delivers a reversible capacity of 233.3 mAh g⁻¹ in half-cells and 210.1 mAh g⁻¹ in full-cells after 100 cycles at 50 mA g⁻¹. At the high charge/discharge rate of 5000 mA g⁻¹, 104.4 mAh g⁻¹ in half-cells and 68 mAh g⁻¹ in full-cells can also be obtained with satisfying stability. In-depth analysis of electrochemical kinetics evidence that the dominated interface capacitive-like storage enables ultrafast uptaking and releasing of Na-ions. This understanding between electrical conductivity and rate performance of SIBs is expected to guild future design to realize effective energy storage.     

Self‐Assembly of Flexible Free‐Standing 3D Porous MoS2‐Reduced Graphene Oxide Structure for High‐Performance Lithium‐Ion Batteries

Flexible freestanding electrodes are highly desired to realize wearable/flexible batteries as required for the design and production of flexible electronic devices. Here, the excellent electrochemical performance and inherent flexibility of atomically thin 2D MoS₂ along with the self‐assembly properties of liquid crystalline graphene oxide (LCGO) dispersion are exploited to fabricate a porous anode for high‐performance lithium ion batteries. Flexible, free‐standing MoS₂–reduced graphene oxide (MG) film with a 3D porous structure is fabricated via a facile spontaneous self‐assembly process and subsequent freeze‐drying. This is the first report of a one‐pot self‐assembly, gelation, and subsequent reduction of MoS₂/LCGO composite to form a flexible, high performance electrode for charge storage. The gelation process occurs directly in the mixed dispersion of MoS₂ and LCGO nanosheets at a low temperature (70 °C) and normal atmosphere (1 atm). The MG film with 75 wt% of MoS₂ exhibits a high reversible capacity of 800 mAh g^?1 at a current density of 100 mA g^?1. It also demonstrates excellent rate capability, and excellent cycling stability with no capacity drop over 500 charge/discharge cycles at a current density of 400 mA g^?1.     

Optimized Cathode for High-Energy Sodium-Ion Based Dual-Ion Full Battery with Fast Kinetics

The most used systems based on the graphite-based cathode show unsatisfactory performance in dual-ion batteries. Developing new type cathode materials with high capacity for new type anions storage is an effective way to improve the total performance of dual-ion batteries. Herein, a protonated polyaniline (P-PANI) cathode is prepared to realize efficient and stable storage of ClO₄^–, and a high reversible capacity of 143 mAh g⁻¹ at 0.2 A g⁻¹ after 200 cycles can be obtained, which is competitive compared with common graphite cathodes. In addition, the highly reversible coordination storage mechanism between ClO₄⁻ and P-PANI cathode is indicated, rather than the labored intercalation reactions between PF₆⁻ and graphite. Subsequently, a full cell (P-PANI//N-PDHC) fabricated with a P-PANI cathode and hard carbon anode (N-PDHC) can deliver a high energy density of 284 Wh kg^–1 for 2000 cycles at 2 A g^–1, and the relevant pouch-type full cell can easily power a smartphone. In general, this work may promote the exploitation of sodium-based dual-ion batteries in practical application.     

Understanding the Charge Storage Mechanism to Achieve High Capacity and Fast Ion Storage in Sodium‐Ion Capacitor Anodes by Using Electrospun Nitrogen‐Doped Carbon Fibers

Microporous nitrogen‐rich carbon fibers (HAT‐CNFs) are produced by electrospinning a mixture of hexaazatriphenylene‐hexacarbonitrile (HAT‐CN) and polyvinylpyrrolidone and subsequent thermal condensation. Bonding motives, electronic structure, content of nitrogen heteroatoms, porosity, and degree of carbon stacking can be controlled by the condensation temperature due to the use of the HAT‐CN with predefined nitrogen binding motives. The HAT‐CNFs show remarkable reversible capacities (395 mAh g^?1 at 0.1 A g^?1) and rate capabilities (106 mAh g^?1 at 10 A g^?1) as an anode material for sodium storage, resulting from the abundant heteroatoms, enhanced electrical conductivity, and rapid charge carrier transport in the nanoporous structure of the 1D fibers. HAT‐CNFs also serve as a series of model compounds for the investigation of the contribution of sodium storage by intercalation and reversible binding on nitrogen sites at different rates. There is an increasing contribution of intercalation to the charge storage with increasing condensation temperature which becomes less active at high rates. A hybrid sodium‐ion capacitor full cell combining HAT‐CNF as the anode and salt‐templated porous carbon as the cathode provides remarkable performance in the voltage range of 0.5–4.0 V (95 Wh kg^?1 at 0.19 kW kg^?1 and 18 Wh kg^?1 at 13 kW kg^?1).     

A High‐Energy Li‐Ion Battery Using a Silicon‐Based Anode and a Nano‐Structured Layered Composite Cathode

High capacity electrodes based on a Si composite anode and a layered composite oxide cathode, Ni‐rich Li[Ni_0.75Co_0.1Mn_0.15]O₂, are evaluated and combined to fabricate a high energy lithium ion battery. The Si composite anode, Si/C‐IWGS (internally wired with graphene sheets), is prepared by a scalable sol–gel process. The Si/C‐IWGS anode delivers a high capacity of >800 mAh g^?1 with an excellent cycling stability of up to 200 cycles, mainly due to the small amount of graphene (～6 wt%). The cathode (Li[Ni_0.75Co_0.1Mn_0.15]O₂) is structurally optimized (Ni‐rich core and a Ni‐depleted shell with a continuous concentration gradient between the core and shell, i.e., a full concentration gradient, FCG, cathode) so as to deliver a high capacity (>200 mAh g^?1) with excellent stability at high voltage (～4.3 V). A novel lithium ion battery system based on the Si/C‐IWGS anode and FCG cathode successfully demonstrates a high energy density (240 Wh kg^?1 at least) as well as an unprecedented excellent cycling stability of up to 750 cycles between 2.7 and 4.2 V at 1C. As a result, the novel battery system is an attractive candidate for energy storage applications demanding a high energy density and long cycle life.