Suppress Dendrite Growth Research Articles

Suppressing dendrite growth and side reactions on Zn metal anode via guiding interfacial anion/cation/H2O distribution by artificial multi-functional interface layer

Introducing artificial interface layer is a cost-effective strategy to inhibit parasitic reactions and dendritic growth on the zinc anode. However, boosting cation transfer while blocking anions and active water molecules through the interface layer is still a formidable challenge at current stage. Here, a zeolitic imidazolate framework (ZIF) based multi-functional interface layer is fabricated to prevent active water molecules reaching the deposition sites while increasing the cation concentration at the interface based on the coordinative self-concentration mechanism and electrokinetic effects, thus effectively inhibiting parasitic reactions and dendrite growth. Specifically, a super-saturated interfacial electrolyte layer is formed in the ZIF-11 layer because a large amount of water and large solvated molecule are removed in advance, eventually inhibiting the generation of hydrogen and basic zinc sulfate. Simultaneously, a thin electric double layer on the wall of the channel inside the interface layer can be formed due to the intense adsorption of zinc ions by the abundant zincophilic nitrogen-containing functional groups in the interface layer, leading to smooth electrokinetic surface conduction and stable deionization shock in the channel. These electrokinetic effects will jointly guide the distribution of zinc ions, thereby forming a uniform shock electrodeposition on the anode surface. Accordingly, the ZIF-11@Cu-Zn based symmetric cells can operate stably for 1800 h, nearly 18 times longer than that of Cu-Zn based symmetric cells at 0.5 mA cm−2. And the ZIF-11@Cu-Zn based aqueous Zn-ions hybrid supercapacitors (AC||ZIF-11@Cu-Zn ZHCs) exhibit a reversible capacity of 58.6 mA h g−1 and the capacity retention is about 96.23% after 5000 cycles. Moreover, AC||ZIF-11@Cu-Zn ZHCs can still run effectively for 5000 cycles even paired with the cathode with commercial-grade loading of 23.3 mg cm−2.

Silver Nanoparticles Guide Uniform Zn Nucleation in the Porous Carbon Skeleton for Dendrite-Free Zinc Metal Anodes

Aqueous zinc-based batteries have been proposed as one of the most promising electrical energy-storage systems owing to their unique advantages of low potential, high theoretical capacity, intrinsic safety, low cost and high ionic conductivity. Despite the current progress in the exploration of the cathode (including NiOOH, MnO2, air cathode, etc.) and electrolyte (neutral ZnSO4, Zn(otf)2, “water in salt”, etc.), the practical implementation of zinc-based battery is still largely impeded by the poor cycle life of Zn metal anode due to the formation of dendrites. One attractive strategy is employing three-dimensional (3D) porous metrics as a host for Zn metal. Among the various 3D hosts, carbon-based materials with lightweight properties, chemical stability and low cost are more attractive. However, due to the high electronic conductivity and overpotential of carbon materials to Zn, the Zn is inclined to plate on the surface of carbon skeletons rather than throughout the whole host materials, which limits the effectiveness of the 3D structural design. Here, we prepared Ag nanoparticles anchored on the 3D porous carbon matrix host (Ag-GS/CNT) by freeze-drying and in situ reduction methods. The uniformly distributed Ag nanoparticles with a lower Zn nucleation barrier compared to carbon guide the Zn deposition within the pores of the 3D hosts. The 3D porous carbon host materials with a large active surface can minimize the local current density and suppress dendrite growth. besides, confining the Zn metal within the host effectively restricts the huge volume change, improving the stability of Zn metal anode upon repeated cycles. Both the Zn–air battery and Zn-ion battery based on Ag-GS/CNT//Zn anode display superior electrochemical performance.

Effect of Tetrapropyl Ammonium Hydroxide on Zn Dendrite Formation for Rechargeable Aqueous Battery

Rechargeable aqueous zinc-ion batteries (AZIB) have captured enormous attention due to their high safety nature, low cost, and environmental friendliness [1]. Recently, improving the performance of AZIBs by optimizing the anode is becoming more promising at the present research area. [2]. Based on current studies, it can be said that, zinc anode suffers from the dendrite formation on the surface during cycling leading to a poor cyclability of a battery and its termination due to short circuit [3]. It is very necessary to study the reasons for dendrite growth and provide an inhibition ways. Herein we report the effect of TPAH (tetrapropyl ammonium hydroxide) as electrolyte additive to suppress dendrite growth in mild acid aqueous electrolyte. All tests were performed in Zn //ZnCi2+LiCl//LiFePO4 system with and without additive. As the result, with the addition of TPAH an enhanced cyclability in consequence with a prolonged cycle life of Zn/LiFePO4 system were observed. The mechanism of TPAH interaction with electrolyte and Zn anode characterization before and after cycling is proposed based on the results of SEM, FTIR and XRD analysis. Acknowledgment This research was supported by the Grant (OPFE2021001 "New materials and devices for defense and aerospace applications") from the Ministry of Digital Development, Innovation and Aerospace Industry of the Republic of Kazakhstan.

Nanoscale surface modification of polymer nanofibers enables uniform lithium nucleation and deposition for stable lithium metal anodes

The growth of lithium dendrites and the huge volume change are the critical issues for the practical application of lithium metal anodes. In this work, a novel strategy is proposed to address the above challenges using oxidized polyacrylonitrile (PAN) nanofibers anchored with well-distributed metal–organic frameworks (MOFs) as the lithium metal anode host. The obtained hybrid structure possesses integrated multiple lithium ion affinities to regulate the lithium ion flux inside the three-dimensional scaffold. On the one hand, the strong chemical lithophilicity is achieved with the abundant surface polar groups from oxidized PAN nanofibers and MOFs. On the other hand, the high capillary force from the microporous structure of MOFs serves them as electrolyte nanoreservoirs enabling improved lithium adsorption. Site-selective lithium nucleation and deposition via nanoscale surface modification of oxidized PAN nanofibers regulates the Li plating/stripping behavior and effectively suppresses dendrite growth. As a result, the symmetrical cell based on the composite anode delivers a prolonged cycling life of 5 times longer than that of bare Cu at a high current density of 3 mA cm−2. Moreover, when paired with the LiNi0.5Co0.2Mn0.3O2 (NCM) cathode, the assembled full cell also exhibits outstanding rate capability and improved cycling performance.

Lithium–copper alloy embedded in 3D porous copper foam with enhanced electrochemical performance toward lithium metal batteries

Suppressing dendrite growth and accommodating volume change, among others, are the main challenges for lithium (Li) metal anode to be used in rechargeable Li batteries. The commercial macroporous copper (Cu) foam current collector may only tackle these challenges to a little extent, and it is usually unable to provide sufficient Li nucleation sites, leading to rapidly increased polarization and unstable cycling performance. Herein, we report a three-dimensional composite anode comprising Li–Cu alloy melt-cast on a commercial Cu foam (CF) current collector (Li–Cu/CF), which can be converted to a unique architecture consisting of Li metal supported by an interconnected CuLix alloy nanowire network formed because of the phase separation, when the molten Li–Cu alloy cools down and gets solidified. Compared to the bare Li foil, the Li–Cu/CF anode shows a smaller polarization and better cycle stability in the carbonate electrolyte at various current densities ranging from 1 to 5 mA/cm2 and is free from dendrite growth upon repeated Li plating/stripping. This can be attributed to the low Li nucleation overpotential and high Coulombic efficiency (96%) during Li plating on and stripping from the thus-obtained hierarchically structured CF collector, as well as the higher proportion of Li2O relative to LiF in the solid-electrolyte interphase layer. Moreover, when assembled in a full cell paired with the LiFePO4 cathode, the Li–Cu/CF anode also exhibits much better rate capability and cycle performance than the bare Li foil. Our work provides a new convenient approach to construct a dendrite-free Li metal anode that can be potentially deployed in the next-generation high energy density rechargeable Li batteries.

Unveiling the Working Mechanism of g-C3N4 as a Protection Layer for Lithium- and Sodium-Metal Anode.

The practical application of lithium-/sodium-metal batteries is currently hindered by severe safety issues caused by uncontrolled continuous dendrite growth. Semiconductive nanoporous g-C3N4 film has been demonstrated to be an effective protection layer for lithium-/sodium-metal anode, which can suppress the growth of dendrite. However, the underlying mechanism of how this semiconductive flexible thin film works to suppress dendrite growth remains unclear. In this work, we investigate the detailed working mechanism of g-C3N4 protection layer employing both density functional theory calculations and ab initio molecular dynamics simulations. The calculation results indicate that g-C3N4 layers show strong adhesion toward the lithium-/sodium-metal surface. When contacting with lithium/sodium metal, the intrinsic triangular nanopores of g-C3N4 will be quickly filled with lithium/sodium atoms, turning the semiconductive g-C3N4 into a metallic material. Lithium/sodium atoms can migrate through the triangular nanopores of stacked g-C3N4 layers via a vacancy-mediated approach with moderate energy barriers of 0.42 and 0.61 eV, respectively. With a low current density, the newly deposited lithium/sodium atoms can permeate through the g-C3N4 protection layers, therefore resulting in a flat electrode surface with no dendrite; with a high current density, however, the newly deposited lithium/sodium atoms cannot transport across the protection layer timely, which will result in the aggregation of lithium/sodium atoms on the surface of the g-C3N4 protection layer.

Aramid nanofiber-based porous membrane for suppressing dendrite growth of metal-ion batteries with enhanced electrochemistry performance

Huge volume changes, uncontrolled side-reactions with electrolytes and irregular dendrite induced short-circuits have impeded practical application in rechargeable batteries based on metallic electrodes including lithium (Li), sodium (Na) and aluminum (Al). Separator with superior mechanical strength represent attractive alternatives to inhibit metal-dendrite growth while preventing capacity fading by stabilizing the solid electrolyte interphase (SEI). However, the challenge of simultaneous retaining high thermal resistance and good electrolyte wettability still have been not overcome in commonly used separators. Here we show that these key properties can be acquired in a porous membrane fabricated from Kevlar microfiber-derived aramid nanofibers (ANFs) prepared in a facile and scalable vacuum filtration method. The obtained ANFs membrane (ANFM), which yields mechanically strong that are markedly effective in inhibit dendrite growth as well as provides good electrolyte wettability to ensure excellent electrochemistry performance. Benefitting from these merits, ANFM guarantee stable cycling of Li-ion or Na-ion rechargeable batteries paired with conventional intercalating cathodes (LiCoO4 and Na2Ti3O7) even at a high operated temperature (150 ℃ for Li-ion battery). Replacing polyolefins-based separator with an ANFM appear to offer a major step towards dendrite-free Li /Na batteries and potentially other metal-ion batteries.

Porous Lithiophilic Li–Si Alloy‐Type Interfacial Framework via Self‐Discharge Mechanism for Stable Lithium Metal Anode with Superior Rate

AbstractLithium is regarded as an ideal anode for next‐generation Li metal batteries (LMB) as it exhibits extraordinarily high theoretical capacity and the lowest electrochemical potential among all anode candidates. However, safety concerns and poor cycling stability of Li induced by uncontrollable dendrite growth and severe side reactions impede its practical application for LMB. Although various strategies for fabricating Li anodes have been suggested, developing high‐rate LMB remains a significant challenge. To address this challenge, the use of a 3D porous Li–Si alloy‐type interfacial framework (LSIF) created via a “self‐discharge” mechanism with the aid of an electrolyte is proposed here. Exploiting the in situ spontaneous prelithiation, lithiophilic Li15Si4 particles are homogenously arranged to build porous 3D LSIF. The balanced ionic/electronic conducting LSIF serves as a stable Li host, helping to suppress dendrite growth and volume expansion during cycling. The LSIF@Li anode possesses a strong affinity toward Li, rapid Li diffusion kinetics, and low nucleation/diffusion barriers. Moreover, the LSIF@Li symmetric cells are capable of stable cycling (over 1000 cycles) even at an ultrahigh current density (15 mA cm–2). When paired with LiNi0.5Co0.2Mn0.3O2 or LiFePO4, LSIF@Li full cells show improved rate capability and long‐term cycling stability (≈2000 cycles) at 10 C.

Thickness-independent scalable high-performance Li-S batteries with high areal sulfur loading via electron-enriched carbon framework

Increasing the energy density of lithium-sulfur batteries necessitates the maximization of their areal capacity, calling for thick electrodes with high sulfur loading and content. However, traditional thick electrodes often lead to sluggish ion transfer kinetics as well as decreased electronic conductivity and mechanical stability, leading to their thickness-dependent electrochemical performance. Here, free-standing and low-tortuosity N, O co-doped wood-like carbon frameworks decorated with carbon nanotubes forest (WLC-CNTs) are synthesized and used as host for enabling scalable high-performance Li-sulfur batteries. EIS-symmetric cell examinations demonstrate that the ionic resistance and charge-transfer resistance per unit electro-active surface area of S@WLC-CNTs do not change with the variation of thickness, allowing the thickness-independent electrochemical performance of Li-S batteries. With a thickness of up to 1200 µm and sulfur loading of 52.4 mg cm−2, the electrode displays a capacity of 692 mAh g−1 after 100 cycles at 0.1 C with a low E/S ratio of 6. Moreover, the WLC-CNTs framework can also be used as a host for lithium to suppress dendrite growth. With these specific lithiophilic and sulfiphilic features, Li-S full cells were assembled and exhibited long cycling stability.

Effective Solid Electrolyte Interphase Formation on Lithium Metal Anodes by Mechanochemical Modification.

Lithium metal batteries are gaining increasing attention due to their potential for significantly higher theoretical energy density than conventional lithium ion batteries. Here, we present a novel mechanochemical modification method for lithium metal anodes, involving roll-pressing the lithium metal foil in contact with ionic liquid-based solutions, enabling the formation of an artificial solid electrolyte interphase with favorable properties such as an improved lithium ion transport and, most importantly, the suppression of dendrite growth, allowing homogeneous electrodeposition/-dissolution using conventional and highly conductive room temperature alkyl carbonate-based electrolytes. As a result, stable cycling in symmetrical Li∥Li cells is achieved even at a high current density of 10 mA cm–2. Furthermore, the rate capability and the capacity retention in NMC∥Li cells are significantly improved.

A high ion-conducting, self-healing and nonflammable polymer electrolyte with dynamic imine bonds for dendrite-free lithium metal batteries

High-performance polymer electrolytes with the capability to self-heal mechanical damage can effectively enhance reliability, safety and service life of the batteries. Herein, a novel polymer electrolyte (PBPE) with excellent self-healing capacity and high ionic conductivity was developed. PBPE with polymer networks cross-linked by highly reversible imine bonds was fabricated by the Schiff-base reaction between poly(ethylene glycol) diamine and benzene-1,3,5-tricarbaldehyde. PBPE can quickly repair the cut damage spontaneously within 1 h at room temperature and recover its mechanical strength and electrochemical properties. The healed PBPE exhibits almost the same ionic conductivities and mechanical properties as the original PBPE shows. PBPE possesses the highest ionic conductivity (4.79 × 10−3 S cm−1 at 30 °C) among the self-healing polymer electrolytes. PBPE can promote the generation of LiF-rich SEI and effectively suppress dendrite growth on Li metal anodes. LiFePO4 (LFP) cells assembled with PBPE exhibit excellent rate capability (discharge capacity of 118.2 mAh g−1 at 5 C rate) and good cycling performance (capacity retention of 97.8% over 125 cycles). More importantly, the healed PBPE can completely recover its properties from damage in LFP cells and enable the cells to possess cycle performance identical to original PBPE.

Sulfur and nitrogen codoped Nb2C MXene for dendrite-free lithium metal battery

Lithium (Li) metal is considered as a promising anode for next-generation energy storage systems, but uncontrollable dendrite and low Coulombic efficiency (CE) impede their commercialization. Herein, by confining Li into sulfur and nitrogen codoped Nb2C MXene, a more practical Li anode with high performance has been synthesized. S and N doping sites serve as extrinsic defects and active sites for reaction, as well as enhance its electroconductivity. Compared with undoped Nb2C, N and S codoped Nb2C is more lithiophilic with synergistic effect, as verified by both density functional theory (DFT) calculation and electrochemcial experiments. Hence, the codoped Nb2C can be used as three dimensional (3D) lithiophilic and conductive host, guiding hostless Li metal to nucleate and plate uniformly. Moreover, the introduction of heteroatoms can broaden the interlayer spacing and stabilize the structure of MXene, avoiding its pulverization and restacking during cycling. As a result, the as-developed Li metal anodes are armed with strong dendrite inhibiting ability and show excellent electrochemical performance, such as high CE, long lifespan and prominent practical performance in full cell. The codoped Nb2C MXene can provide a new avenue for the development of alkali metal batteries and shed light on the research of suppressing dendrite growth.

Transient Rechargeable Battery with a High Lithium Transport Number Cellulosic Separator

AbstractTransient batteries play a pivotal role in the development of fully autonomous transient devices, which are designed to degrade after a period of stable operation. Here, a new transient separator‐electrolyte pair is introduced for lithium ion batteries. Cellulose nanocrystals (CNCs) are selectively located onto the nanopores of polyvinyl alcohol membranes, providing mobile ions to interact with the liquid electrolyte. After lithiation of CNCs, membranes with electrolyte uptake of 510 wt%, ionic conductivities of 3.077 mS·cm–1, electrochemical stability of 5.5 V versus Li/Li+, and high Li+ transport numbers are achieved. Using an organic electrolyte, the separators enable stable Li metal deposition with no dendrite growth, delivering 94 mAh·g–1 in Li/LiFePO4 cells at 100 mA·g–1 after 200 cycles. To make the separator‐electrolyte pair transient and non‐toxic, the organic electrolyte is replaced by a biocompatible ionic liquid. As a proof of concept, a fully transient Li/V2O5 cell is assembled, delivering 55 mAh·g–1 after 200 cycles at 100 mA·g–1. Thanks to the reversible Li plating/stripping, dendrite growth suppression, capacity retention, and degradability, these materials hold a bright future in the uptake of circular economy concepts applied to the energy storage field.

Enhanced Safety and Performance of High-Voltage Solid-State Sodium Battery through Trilayer, Multifunctional Electrolyte Design

Solid-state electrolytes are promising to resolve the safety hazards and low energy density of traditional liquid batteries. However, the practical application of these electrolytes has been impaired by the low ionic conductivity and an unstable interface present with a high-voltage cathode. Here, an improvement of ionic conductivity, interface, and safety was achieved by impregnating anti-oxidation polyacrylonitrile (PAN) and anti-reduction poly(ethylene oxide) (PEO) into a sandwich sodium superionic conductor (NASICON) framework with a dense core and porous outer layers. Using this sandwich composite electrolyte (SCE), a high ionic conductivity of 4.13×10−4 S cm−1 at 30°C was obtained owing to long-range and continuous ionic conduction pathways in the porous network. The interfacial resistance was greatly improved through the creation of a compact and stable interface. More importantly, the safety of this SCE is improved through the in-situ formation of a central, dense NASICON layer, which suppressed dendrite growth. Furthermore, a high-voltage solid-state battery combining Na3V2(PO4)2F3 (NVPF) with this SCE exhibited an impressive rate performance with long cycle life. This study offers a promising strategy to design ultra-safe, high energy density, solid-state batteries.

Controlling the Spatial Dimensions of Nanostructured Electrolytes to Stabilize Dendritic Electrodeposition of Silver

The tendency of metals to form uncontrolled dendritic morphologies during electrodeposition hinders the development of safe and reliable metal batteries. Multiphase nanostructured electrolytes can suppress dendritic growth if the mechanical modulus of the electrolyte is high relative to that of the metal or if the conducting channels are confined to nanoscale dimensions. Direct visualization and analysis of electrodeposition within polymeric nanostructures elucidates the structure−property relationships and mechanisms underlying the suppression of dendrite growth. To overcome these challenges, we introduce here a generalizable platform by which we can directly characterize electrodeposited metal morphologies in well-defined, multiphase nanostructured electrolytes by top-down SEM imaging [1]. This approach requires no destructive sample preparation techniques between electrodeposition and imaging. The platform consists of coplanar electrodes coated by polymeric structures consisting of alternating ion conducting and nonconducting material which are precisely created by lithography and etch techniques. These fabricated polymeric structures are designed to carefully model deposition of metals in nanostructured polymeric separators and electrolytes.In this study we track the electrodeposition of silver ions (Ag+) dissolved in dry, aprotic poly(ethylene oxide) (PEO) polymer electrolyte confined within channels that are defined by a microfabricated nonconductive polystyrene structures. We find that Ag metal electrodeposition occurs only in the conductive domains with no significant deformation of the adjacent low-modulus nonconductive and confining domains. Moreover, we have shown that the Ag metal deposit morphology was strongly dependent on the dimensions of the conducting domains. When confinement width was similar in scale to the critical length scale for unstable deposition, the metal morphology was dense, unbranched filaments. Gradually increasing the confinement width led to branched dendritic deposition, although the side branch feature size was limited by the size of the confinement. These results demonstrate that in addition to mechanical and transport properties, the nanodimension of the structured electrolyte can also serve to stabilize dendritic morphology growth. This work highlights critical parameters for design of structured battery components such as solid-electrolytes, separators, and current collectors.[1] Sharon, D.; Bennington, P.; Patel, S.N.; Nealey, P.F.*, “Stabilizing Metal Electrodeposition by Limiting Spatial Dimensions in Nanostructured Electrolytes,” ACS Energy Lett. 2020, 5, 2889−2896. Figure 1

Lithium propanesulfonyl(trifluoromethylsulfonyl)imide grafted polybenzimidazole as a self-supporting single ion conducting polymer electrolyte membrane for lithium metal secondary batteries

Dendrite growth and unstable solid electrolyte interphase are two challenges for lithium metal secondary batteries. Immobilization of anions to allow the transportation of cations only, namely single ion conductor, can prevent from concentration polarization and therefore is likely to suppress dendrite growth. In this article, poly(4,4′-(diphenyl ether)-5,5′-bibenzimidazole) (PBI) grafted with lithium propanesulfonyl(trifluoromethylsulfonyl)imide (LiPSTFSI) is found to form a uniform self-supporting single ion conducting polymer electrolyte membrane (PBI-g-LiPSTFSI). The ionic conductivity of the gel polymer electrolyte is 0.15 mS cm−1 at 25 °C. Coupled with a high lithium ion transference number of 0.91, the polymer electrolyte can withstand a 1000 h galvanostatic cycling at 0.5 mA cm−2 with a Li plating/stripping capacity of 2.5 mAh cm−2 without short circuit. Even increasing the mass loading of LiFePO4 up to 10.2 mg cm−2, the single ion conducting lithium metal secondary battery can deliver 166 mAh g−1 at 0.1 C, 160 mAh g−1 at 0.2 C and 152 mAh g−1 at 0.3 C. Because the rigid polymer chains and strong pi-pi stacking of PBI provide high mechanical strength and excellent thermal stability, PBI-g-LiPSTFSI is a promising single ion conducting polymer electrolyte for safe lithium metal secondary batteries.

Achievement of high-cyclability and high-voltage Li-metal batteries by heterogeneous SEI film with internal ionic conductivity/external electronic insulativity hybrid structure

Establishing electronic hinder/ionic transfer pathway in SEI film is key issue for high-performance Li-metal anodes (LMA), which requires the SEI with high ionic conductivity to enable fast Li+ diffusion and regulated Li deposition behavior, and poor electronic conductivity to block the electrolyte consumption. Herein, we propose a strategy to construct heterogeneous SEI via selective reduction of electrolytes components to improve Li stability and suppress dendrite growth. The inner N-rich sub-layer of SEI film enables fast Li+ transportation for nodule-like Li deposition while the outer C-rich sub-layer of SEI film exhibits an electronic insulation property to block electrolyte decomposition. This hybrid SEI endows the LMA with high Coulombic efficiency (99.0%), long lifespan, and dendrite suppression. Theoretical calculations, XPS and AFM were employed to examine the heterogeneous SEI structure and clarify its formation mechanism. A high-capacity retention of 91.6% after 160 cycles at 0.5 C in LiCoO2/Li pouch cells with ultra-thin Li anodes (25 μm) and low N/P ratio (1.67), and an excellent performance with 85.7% capacity retention after 300 cycles at higher charge potential (4.5 V) was also obtained. The insight in heterogeneous SEI formation provides new opportunities for rational electronic/ionic transfer pathway construction for achieving high-performance Li-metal batteries.

Manipulating the ion-transference and deposition kinetics by regulating the surface chemistry of zinc metal anodes for rechargeable zinc-air batteries

Aqueous zinc-air battery (ZAB) has attractive features as the potential energy storage system such as high safety, low cost and good environmental compatibility. However, the issue of dendrite growth on zinc metal anodes has seriously hindered the development of ZAB. Herein, the N-doped carbon cloth (NC) prepared via magnetron sputtering is explored as the substrate to induce the uniform nucleation of zinc metal and suppress dendrite growth. Results show that the introduction of heteroatoms accelerates the migration and deposition kinetics of Zn2+ by boosting the desolvation process of Zn2+, eventually reducing the nucleation overpotential. Besides, theoretical calculation results confirm the zincophilicity of N-containing functional group (such as pyridine N and pyrrole N), which can guide the nucleation and growth of zinc uniformly on the electrode surface by both promoting the redistribution of Zn2+ in the vicinity of the surface and enhancing its interaction with zinc atoms. As a result, the half-cell assembled with magnetron sputtered carbon cloth achieves a high zinc stripping/plating coulombic efficiency of 98.8% and long-term stability of over 500 cycles at 0.2 mA cm−2. And the Coulombic efficiency reached about 99.5% at the 10th cycle and maintained for more than 210 cycles at a high current density of 5.0 mA cm−2. The assembled symmetrical battery can deliver 220 plating/stripping cycles with ultra-low voltage hysteresis of only 11 mV. In addition, the assembled zinc-air full battery with NC-Zn anode delivers a high special capacity of about 429 mAh gZn−1 and a long life of over 430 cycles. The effectiveness of surface functionalization in promoting the transfer and deposition kinetics of Zn2+ presented in this work shows enlightening significance in the development of metal anodes in aqueous electrolytes.

Solid-state rigid-rod polymer composite electrolytes with nanocrystalline lithium ion pathways.

A critical challenge for next-generation lithium-based batteries lies in development of electrolytes that enable thermal safety along with the use of high-energy-density electrodes. We describe molecular ionic composite electrolytes based on an aligned liquid crystalline polymer combined with ionic liquids and concentrated Li salt. This high strength (200 MPa) and non-flammable solid electrolyte possesses outstanding Li+ conductivity (1 mS cm-1 at 25 °C) and electrochemical stability (5.6 V versus Li|Li+) while suppressing dendrite growth and exhibiting low interfacial resistance (32 Ω cm2) and overpotentials (≤120 mV at 1 mA cm-2) during Li symmetric cell cycling. A heterogeneous salt doping process modifies a locally ordered polymer-ion assembly to incorporate an inter-grain network filled with defective LiFSI and LiBF4 nanocrystals, strongly enhancing Li+ conduction. This modular material fabrication platform shows promise for safe and high-energy-density energy storage and conversion applications, incorporating the fast transport of ceramic-like conductors with the superior flexibility of polymer electrolytes.

An All-Solid-State Battery with a Tailored Electrode–Electrolyte Interface Using Surface Chemistry and Interlayer-Based Approaches

Major challenges in the development of solid-state batteries using garnet-type solid-state electrolytes (SSEs) include suppressing dendrite growth, improving moisture stability, and reducing interf...