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The pursuit of advanced materials to meet the escalating demands of energy storage system has led to the emergence of vertical graphene (VG) as a highly promising candidate. With its remarkable strength, stability, and conductivity, VG has gained significant attention for its potential to revolutionize energy storage technologies. This comprehensive review delves deeply into the synthesis methods, structural modifications, and multifaceted applications of VG in the context of lithium–ion batteries, silicon-based lithium batteries, lithium–sulfur batteries, sodium–ion batteries, potassium–ion batteries, aqueous zinc batteries, and supercapacitors. The review elucidates the intricate growth process of VG and underscores the paramount importance of optimizing process parameters to tailor VG for specific applications. Subsequently, the pivotal role of VG in enhancing the performance of various energy storage and conversion systems is exhaustively discussed. Moreover, it delves into structural improvement, performance tuning, and mechanism analysis of VG composite materials in diverse energy storage systems. In summary, this review provides a comprehensive look at VG synthesis, modification, and its wide range of applications in energy storage. It emphasizes the potential of VG in addressing critical challenges and advancing sustainable, high-performance energy storage devices, providing valuable guidance for the development of future technologies. [ABSTRACT FROM AUTHOR]

Anode cell reversal typically leads to severe carbon corrosion and catalyst layer collapse, which significantly compromises the durability of proton exchange membrane fuel cells. Herein, three types of commercial carbon supports with various structures are facilely coated by polyaniline (PANI) and subsequently fabricated into reversal‐tolerant anodes (RTAs). Consequently, the optimized PANI‐coated catalyst RTAs demonstrate enhanced polarization performance and improved reversal tolerance compared to their uncoated counterparts, thus confirming the universality of this coating strategy. Essentially, the surface engineering introduced by PANI coating incorporates abundant N‐groups and enhances coulombic interactions with ionomer side chains, which in turn reduces lower carbon exposure, promotes more uniform Pt deposition, and ensures better ionomer distribution. Accordingly, the membrane‐electrode‐assembly containing the Pt/PANI/XC‐72R‐1+IrO2 RTA presents a 100 mV (at 2500 mA cm−2) polarization performance improvement and 26‐fold reduction in the degradation rate compared to the uncoated counterpart. This work provides a universal strategy for developing durable anodes and lays the groundwork for the practical fabrication of high‐performance, low‐degradation RTA. [ABSTRACT FROM AUTHOR]

Lithium (Li) metal anodes offer significantly higher theoretical capacity than graphite anodes but face challenges in terms of stability and safety due to dendrite growth and solid electrolyte interphase (SEI) instability. To address these issues, a hybrid Li‐ion/metal anode is proposed to enhance cycling stability by selectively forming lithiated graphite, thereby promoting uniform Li deposition. By laser‐processing commercial graphite paper (GP), a laser‐ablated graphite paper (LGP) anode featuring grooved structures enriched with oxygen‐containing functional groups is fabricated. These structures expose electrochemically active edge planes that facilitate Li‐ion adsorption and intercalation in graphite flakes. The lithophilic functional groups and lithiated graphite (LiC6) inside grooves promote selective Li metal deposition, inhibit dendrite growth, and enhance energy density. The Li||LGP half‐cell operated stably over 300 cycles at 1 mA cm−2 with a Coulombic efficiency over 99%. LGP||LiFePO4 full‐cell maintained a capacity of 157 mAh g−1 after 150 cycles at 0.5 C, compared to 137.5 mAh g−1 for GP||LiFePO4 cells. The LGP full‐cell also shows a capacity of 104 mAh g−1 with 91% capacity retention after 500 cycles at 5 C, whereas the GP full‐cell declined rapidly. These results highlight the potential of the approach for improving the cycling stability and performance of Li metal batteries. [ABSTRACT FROM AUTHOR]

Hydrogel electrolytes have been widely explored in aqueous zinc‐iodine batteries (AZIBs), in light of their intrinsic strong water‐retention capability and superior flexibility of hydrogel network. However, hydrogel‐based AZIBs are still facing challenges due to the inferior ionic conductivity, dendrite formation, and corresponding fatigue‐induced damage. Herein, a hydrogel electrolyte is designed and engineered with preferentially aligned porous structures, where Zn2+ can promptly transport along the pores. AZIBs fabricated from the hydrogel electrolyte exhibited distinct cycling stability over 1,000 h (500 cycles) at 0.5 mA cm−2. Moreover, in light of the substantially improved mechanical robustness, the hydrogel electrolyte network remained intact over a 27,000‐cycle charging/discharging test at 5 A g−1, with a slight change in capacity, surpassing most previously reported AZIBs. Such kind of hydrogel electrolyte‐based AZIBs can be further explored as the flexible power system for wearable devices, enabling significantly accelerated wound healing through electrical stimulation over the epidermal wounds. This work sheds light on hydrogel electrolytes design for long‐life aqueous zinc‐based batteries, with great potential as power systems for wearable and implantable devices. [ABSTRACT FROM AUTHOR]

The germanium (Ge) anode attains wide attention in lithium‐ion batteries because of its high theoretical volumetric capacity (8646 mAh cm−3). However, the huge volume expansion (≈230%) results in its poor electrochemical performances. The strategies reported in the literature to solve the issue often cause a low packing density, lowering the volumetric capacity. Here, a pressure‐induced route is proposed to fabricate a Ge architecture, in which nano‐sized Ge (≈15 nm) is encapsulated by robust TiO2 and highly conductive carbon, which offer the advantages of a low stress–strain characteristic, low volume expansion in thickness change, high electrical conductivity (463.2 S m−1), high Li‐ion diffusion coefficient (9.55 × 10−9–8.51 × 10−12 cm2 s−1), and high tapping density (1.79 g cm−3). As a result, the dense architecture obtains outstanding volumetric capacities of 3559.8 mAh cm−3 at 0.1 A g−1 and 2628.2 mAh cm−3 at 20 A g−1, along with excellent cycling life over 5000 cycles at 10 A g−1. Remarkably, the full cell achieves a high volumetric energy density of 1760.1 Wh L−1, along with impressive fast‐charging performances and long cycling life. This work provides a new synthesis strategy and deep insight into the design of high‐volumetric capacity alloy‐based lithium‐ion‐battery anodes. [ABSTRACT FROM AUTHOR]

LiNixCoyAlzO2 (NCA) and LiNixCoyMnzO2 (NCM) have become extensively utilized as cathodes in lithium‐ion batteries for consumer electronics, electric vehicles, and energy storage applications that necessitate consistent power output over prolonged periods and under varying environmental conditions. A crucial structural degradation issue leading to cycling‐induced deterioration, rapid loss of cell capacity/voltage, and the onset of undesirable thermal runaway events involves the decay of cathode materials enriched in nickel. This contribution offers a comprehensive evaluation of cutting‐edge strategies in engineering and material design to enhance the structural stability of cathode materials and reduce detrimental oxygen evolution reactions. It also provides the most recent discoveries regarding oxygen release phenomena and associated mechanisms contributing to structural breakdown in high‐nickel cathodes. The primary source of oxygen depletion and the ensuing structural deterioration caused are thoroughly examined. Additionally, the kinetic mechanisms responsible for oxygen loss are scrutinized, and measures to mitigate resulting electrochemical degradation are elaborated. This overview can guide researchers in the development of oxygen‐containing cathode materials in the future, where oxygen leakage is of lesser concern compared to other forms of deterioration. [ABSTRACT FROM AUTHOR]

Iron sulfide (FeS) has been extensively studied as sodium‐ion battery anodes due to its high theoretical capacity (609 mAh g−1), but its large volume expansion and low electrical conductivity result in unsatisfactory cycling life and poor rate performance. Moreover, the sodium ion storage mechanism of FeS at a voltage range of 0.01–1 V involving conversion reactions and subsequent ion storage process is unclear yet. Here, the study proposes a vapor‐pressure induced synthesis route to fabricate FeS/C yolk‐shell structure that ultrathin carbon layers coat on the surface of FeS nanosheets, which can accommodate volume expansion of FeS during sodiation observed via in situ transmission electron microscope and improve its electrical conductivity. Remarkably, an in situ magnetometry reveals that vast spin‐polarized electrons can be injected into superparamagnetic Fe nanoparticles (≈3 nm) formed during conversion reaction to induce evolution of electrode magnetization between 0.01 and 1 V, during which spin‐polarized surface capacitance effect occurs at Fe/Na2S interfaces to increase extra ion storage and boost ion transport stably. Consequently, the FeS/C yolk‐shell nanosheets deliver a high reversible capacity of 664.9 mAh g−1 at 0.1 A g−1, and 300.4 mAh g−1 after 10 000 cycles at 10 A g−1 with a capacity retention of 81.1%. [ABSTRACT FROM AUTHOR]

Li-rich Mn-based cathode material (LRM) is one of the most promising cathode materials for achieving high energy density lithium-ion batteries; however, its irreversible anion redox limits its advantages. Herein, these challenges are resolved by introducing a dual modification approach involving Ce, B co-doping and CeO2 aggregation on Li1.184Ni0.136Co0.136Mn0.544O2 (CB-LRM). Density functional theory (DFT) proves that Ce, B co-doping significantly regulates the Mn 3d and O 2p energy bands to improve the stability of lattice oxygen, inhibiting oxygen loss and structural distortion during prolonged cycling. Furthermore, High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) reveals that Ce, B co-doping motivated the transformation from layers to disordered rock salt. Accordingly, the CB-LRM electrode exhibits an impressive cyclability, with 89.6% and 80% capacity retention after 200 cycles at 1C and 3C, respectively, surpassing unmodified LRM (57.3% and 56.8%). This work proposes a novel approach to designing long-life, high-energy-density layered oxide cathodes for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Silicon (Si) is widely used as a lithium‐ion‐battery anode owing to its high capacity and abundant crustal reserves. However, large volume change upon cycling and poor conductivity of Si cause rapid capacity decay and poor fast‐charging capability limiting its commercial applications. Here, we propose a multilevel carbon architecture with vertical graphene sheets (VGSs) grown on surfaces of subnanoscopically and homogeneously dispersed Si–C composite nanospheres, which are subsequently embedded into a carbon matrix (C/VGSs@Si–C). Subnanoscopic C in the Si–C nanospheres, VGSs, and carbon matrix form a three‐dimensional conductive and robust network, which significantly improves the conductivity and suppresses the volume expansion of Si, thereby boosting charge transport and improving electrode stability. The VGSs with vast exposed edges considerably increase the contact area with the carbon matrix and supply directional transport channels through the entire material, which boosts charge transport. The carbon matrix encapsulates VGSs@Si–C to decrease the specific surface area and increase tap density, thus yielding high first Coulombic efficiency and electrode compaction density. Consequently, C/VGSs@Si–C delivers excellent Li‐ion storage performances under industrial electrode conditions. In particular, the full cells show high energy densities of 603.5 Wh kg−1 and 1685.5 Wh L−1 at 0.1 C and maintain 80.7% of the energy density at 3 C. [ABSTRACT FROM AUTHOR]

Silicon (Si) anodes, known for their high capacity, confront obstacles such as volume expansion, the solid–electrolyte interface (SEI) formation, and limited cyclability, driving ongoing research for innovative solutions to enhance their performance in next‐generation lithium‐ion batteries (LIBs). This comprehensive review explores the forefront of one‐dimensional (1D) Si/carbon anodes for high‐performance LIBs. This review delves into cutting‐edge strategies for fabricating 1D Si/carbon structures, such as nanowires, nanotubes, and nanofibers, highlighting their advantages in mitigating volume expansion, enhancing electron/ion transport, and bolstering cycling stability. The review showcases remarkable achievements in 1D Si/carbon anode performance, including exceptional capacity retention, high‐rate capability, and prolonged cycle life. Challenges regarding scalability, cost‐effectiveness, and long‐term stability are addressed, providing insights into the path to commercialization. Additionally, future directions and potential breakthroughs are outlined, guiding researchers and industries toward harnessing the potential of 1D Si/carbon anodes in revolutionizing energy storage. [ABSTRACT FROM AUTHOR]

The irreversible oxygen redox and structural degradation of LiNi0.8Co0.1Mn0.1O2 (NCM811) at a 4.5 V high voltage cause a severe decline in cycling performance for lithium‐ion batteries. In this study, a novel approach is proposed to enhance the anionic redox chemistry and stability of NCM811 cathode material by introducing gaseous selenium. Seβ+ species are selectively adsorbed within oxygen vacancies, leading to the continuous replacement of Oα− to form a stable O–TM–Se bond during deep charging. Furthermore, Selenium modification improves cationic redox efficiency and alleviates Oα− (α < 2) outward migration, increases oxygen vacancy formation energy. The redox activity of oxygen is diminished, facilitating improved reversibility of oxygen redox and effectively inhibiting irreversible oxygen escape. Additionally, Selenium increases the energy barrier for phase transition, effectively suppressing irreversible phase transition and Ni migration. Selenium reacts with escaping oxygen to form SeO2, effectively reducing side reactions during cycling. As a result, the proposed approach significantly inhibits irreversible oxygen release, leading to remarkable cyclic stability with 87.5% capacity retention after 300 cycles at 1C at 4.5 V and maintained 192.9 mAh g−1 after 150 cycles under 60C. The Se modification realizes stability anionic redox strategy to design novel high‐energy‐density cathode materials with superior cycling performance. [ABSTRACT FROM AUTHOR]