Latest ArticlesSilicon-air batteries (SABs), a new type of semiconductor air battery, have a high energy density. However, some side reactions in SABs cause Si anodes to be covered by a passivation layer to prevent continuous discharge, and the anode utilization rate is low. In this work, reduced graphene oxide (RGO) fabricated via high-temperature annealing or L-ascorbic acid (L.AA) reduction was first used to obtain Si nanowires/RGO-1000 (Si NWs/RGO-1000) and Si nanowires/RGO-L.AA (Si NWs/RGO-L.AA) composite anodes for SABs. It was found that RGO suppressed the passivation and self-corrosion reactions and that SABs using Si NWs/RGO-L.AA as the anode can discharge for more than 700 h, breaking the previous performance of SABs, and that the specific capacity was increased by 90.8% compared to bare Si. This work provides a new solution for the design of high specific capacity SABs with nanostructures and anode protective layers.
The ultra-high nickel cathode material has important application prospect in power lithium-ion batteries. However, the poor structural stability and serious surface/interfacial side reactions during long cycles severely hinder the material's practical application. In this paper, Cs+ doping and polymethyl methacrylate (PMMA) coating are used to synergistically modify the NCM955 material. The results show that the corresponding discharge specific capacity of NCMCs-2@P-2 material reaches 152.02 mAh/g at 1 C (1 C = 200 mA/g) and 125.66 mAh/g at 5 C after 300 cycles, and the capacity retention is 78.11% and 72.21%, respectively. In addition, it still maintains 156.36 mAh/g discharge specific capacity at 10 C, and these rate and cycle properties exceed those reported on ultra-high nickel cathode material. Moreover, NCMCs-2@P-2 material has higher migration energy barrier of Ni2+ and lower migration energy barrier of Li+ than that of NCM955 material. Therefore, NCMCs-2@P-2 material has excellent electrochemical properties, which has been proved by a series of structural characterization, theoretical calculation and performance test. The synergistic enhancement of Cs+ doping and PMMA coating accelerates lithium ion diffusion kinetics, stabilizes crystal structure, and inhabits surface/interface side reaction.
Flexible zinc-ion batteries (FZIBs) have been acknowledged as a potential cornerstone for the future development of flexible energy storage, yet conventional FZIBs still encounter challenges, particularly concerning performance failure at low temperatures. To address these challenges, a novel anti-freezing leather gel electrolyte (AFLGE-30) is designed, incorporating ethanol as a hydrogen bonding acceptor. The AFLGE-30 demonstrates exceptional frost resistance while maintaining favorable flexibility even at −30 ℃; accordingly, the battery can achieve a high specific capacity of about 70 mAh/g. Cu//Zn battery exhibits remarkable stability at room temperature, retaining ~96% efficiency after 120 plating/stripping cycles at 1 mA/cm2. Concurrently, the Zn//Zn symmetric batteries demonstrate a lifespan of 4100 h at room temperature, which is attributed to the enhancement of Zn2+ deposition kinetics, restraining the formation of zinc dendrites. Furthermore, FZIBs exhibit minimal capacity loss even after bending, impacting, or burning. This work provides a promising strategy for designing low-temperature-resistant FZIBs.
The sluggish reaction kinetics of the oxygen evolution reaction (OER) and methanol oxidation reaction (MOR) remain obstacles to the commercial promotion of water splitting and direct methanol fuel cells. Considering the vital role of noble metals in electrocatalytic activity, this work focuses on the rational synthesis of Ni-noble metal composite nanocatalysts for overcoming the drawbacks of high cost and susceptible oxidized surfaces of noble metals. The inherent catalytic activity is improved by the altered electronic structure and effective active sites of the catalyst induced by the size effect of noble metal clusters. In particular, a series of Ni-noble metal nanocomposites are successfully synthesized by partially introducing noble metal into Ni with porous interfacial defects derived from Ni-Al layered double hydroxide (LDH). The Ni10Pd1 nanocomposite exhibits high OER catalytic activity with an overpotential of 0.279 V at 10 mA/cm2, surpassing Ni10Ag1 and Ni10Au1 counterparts. Furthermore, the average diameter of Pd clusters gradually increases from 5.57 nm to 44.44 nm with the increased proportion of doped Pd, leading to the passivation of catalytic activity due to the exacerbated surface oxidation of Pd in the form of Pd2+. After optimization, Ni10Pd1 delivers significantly enhanced OER and MOR electroactivities and long-term stability compared to that of Ni2Pd1, Ni1Pd1 and Ni1Pd2, which is conducive to the effective utilization of Pd and alleviation of surface oxidation.
Sodium metal has been widely studied in the field of batteries due to its high theoretical specific capacity (~1,166 mAh/g), low redox potential (-2.71 V compared to standard hydrogen electrode), and low-cost advantages. However, problems such as unstable solid electrolyte interface (SEI), uncontrolled dendrite growth, and side reactions between solid-liquid interfaces have hindered the practical application of sodium metal anodes (SMAs). Currently, lots of strategies have been developed to achieve stabilized sodium metal anodes. Among these strategies, modified metal current collectors (MCCs) stand out due to their unique role in accommodating volumetric fluctuations with superior structure, lowering the energy barrier for sodium nucleation, and providing guided uniform sodium deposition. In this review, we first introduced three common metal-based current collectors applied to SMAs. Then, we summarized strategies to improve sodium deposition behavior by optimally engineering the surface of MCCs, including surface loading, surface structural design, and surface engineering for functional modification. We have followed the latest research progress and summarized surface optimization cases on different MCCs and their applications in battery systems.
For large-scale energy storage devices, all-solid-state sodium-ion batteries (SIBs) have been revered for the abundant resources, low cost, safety performance and a wide operating temperature range. Na-ion solid-state electrolytes (Na-ion SSEs) are the critical parts and mostly determine the electrochemical performance of SIBs. Among the studied ones, inorganic Na-ion SSEs stand out for their good safety performance and high ionic conductivity. In this review, we outline the research progress of inorganic SSEs in SIBs based on the perspectives of crystal structure, performance optimization, synthesis methods, all-solid-state SIBs, interface modification and related characterization techniques. We hope to provide some ideas for the design of future high-performance Na-ion SSEs.
Sodium metal batteries (SMBs) have drawn much attention as complement to lithium metal batteries for next generation high-energy batteries. However, it is still a big challenge to enhance their cycling stability without sufficient sodium reserve in anode, due to the non-uniform Na plating/stripping and uncontrolled Na dendrite growth. Herein, a dual layer host consists of sodiophilic graphene@antimony nanoparticles bottom layer and 3D polyacrylonitrile nanofiber top layer (PAN-G@Sb) is employed to enable highly reversible Na plating/stripping. Thanks to the uniform Na deposition, PAN-G@Sb delivers an outstanding average Coulombic efficiency of 99.8%, highly reversible Na plating/stripping for 1000 cycles at 2.0 mA/cm2, as well as over 1000 h of stable operation in symmetric cells. When paired with a high mass loading Na3V2(PO4)3 (NVP) cathode (16.2 mg/cm2), the full cell (N/P ratio = 1.4) also displays prominent capacity retention of 98.7% after 250 cycles with a high energy density of 284.6 Wh/kg. Moreover, PAN-G@SbNVP anode-free full cell also shows an excellent capacity retention of 91.0% after 50 cycles at 0.5 C, exhibiting the stable operation of high energy SMBs.
Solid-state batteries (SSBs) with thermal stable solid-state electrolytes (SSEs) show intrinsic capacity and great potential in energy density improvement. SSEs play critical role, however, their low ionic conductivity at room temperature and high brittleness hinder their further development. In this paper, polypropylene (PP)-polyvinylidene fluoride (PVDF)-Li1.3Al0.3Ti1.7(PO4)3 (LATP)-Lithium bis(trifluoromethane sulphonyl)imide (LiTFSI) multi-layered composite solid electrolyte (CSE) is prepared by a simple separator coating strategy. The incorporation of LATP nanoparticle fillers and high concentration LiTFSI not only reduces the crystallinity of PVDF, but also forms a solvation structure, which contributes to high ionic conductivity in a wide temperature. In addition, using a PP separator as the supporting film, the mechanical strength of the electrolyte was improved and the growth of lithium dendrites are effectively inhibited. The results show that the CSE prepared in this paper has a high ionic conductivity of 6.38×10–4 S/cm at room temperature and significantly improves the mechanical properties, the tensile strength reaches 11.02 MPa. The cycle time of Li/Li symmetric cell assembled by CSE at room temperature can exceed 800 h. The Li/LFP full cell can cycle over 800 cycles and the specific capacity of Li/LFP full cell can still reach 120 mAh/g after 800 cycles at 2 C. This CSE has good cycle stability and excellent mechanical strength at room temperature, which provides an effective method to improve the performance of solid electrolytes under moderate condition.
Lithium metal batteries, with their light mass anode and high theoretical specific capacity of 3860 mAh/g, have great potential for development in achieving high energy density. However, the generation of lithium dendrites and the loss of dead lithium pose a serious threat to the safety and long-cycle stability of batteries. Herein, we utilize the Lewis acid-base interaction principle for lithium-ion migration regulation. Through loading solid-acids onto molecular sieves to immobilize Lewis base (PF6−), we achieve accelerated dissociation of lithium salts and successfully increase the lithium ion transference number to 0.44. Lewis acid-base interaction helps lithium metal batteries achieve more uniform lithium deposition, with an average CE improved to 92.8%. The symmetrical cells can be plated/stripped stably for more than 800 h of cycling. Full cell with high surface-loaded LFP cathode (14 mg/cm2) exhibits impressively high capacity retention of 90.7% after 120 cycles at 0.5 C.
Rationally design the morphology and structure of electroactive nanomaterials is an effective approach to enhance the performance of aqueous batteries. Herein, we co-engineered the hollow architecture and interlayer spacing of layered double hydroxides (LDH) to achieve high electrochemical activity. The hierarchical hollow LDH was prepared from bimetallic zeolitic imidazolate frameworks (ZIF) by a facile cation exchange strategy. Zn and Cu elements were selected as the second metals incorporated in Co-ZIF. The characteristics of the corresponding derivatives were studied. Besides, the transformation mechanism of CoZn-ZIF into nanosheet-assembled hollow CoZnNi LDH (denoted as CoZnNi-OH) was systematically investigated. Importantly, the interlayer spacing of CoZnNi-OH expands due to Zn2+ incorporation. The prepared CoZnNi-OH offers large surface area, exposed active sites, and rapid mass transfer/diffusion rate, which lead to a significant enhancement in the specific capacitance, rate performance, and cycle stability of CoZnNi-OH electrode. In addition, the aqueous alkaline CoZnNi-OH//Zn showed a maximum energy density/power density of 0.924 mWh/cm2, 8.479 mW/cm2. This work not only raises an insightful strategy for regulating the morphology and interlayer spacing of LDH, but also provides a reference of designing hollow nickel-based nanomaterials for aqueous batteries.