Gradiently Polymerized Solid Electrolyte Meets with Micro

May 2, 2018 - Looking ahead to the biggest issues for chemistry worldwide, including geopolitical and economic drivers,... SCIENCE CONCENTRATES ...
0 downloads 0 Views 4MB Size
Download PDF
Research Article www.acsami.org

Cite This: ACS Appl. Mater. Interfaces 2018, 10, 18005−18011

Gradiently Polymerized Solid Electrolyte Meets with Micro-/ Nanostructured Cathode Array Wei Dong,†,‡ Xian-Xiang Zeng,§ Xu-Dong Zhang,†,‡ Jin-Yi Li,†,‡ Ji-Lie Shi,†,‡ Yao Xiao,† Yang Shi,†,‡ Rui Wen,†,‡ Ya-Xia Yin,†,‡ Tai-shan Wang,†,‡ Chun-Ru Wang,*,†,‡ and Yu-Guo Guo*,†,‡ †

Downloaded via STOCKHOLM UNIV on January 19, 2019 at 11:37:25 (UTC). See https://pubs.acs.org/sharingguidelines for options on how to legitimately share published articles.

CAS Key Laboratory of Molecular Nanostructure and Nanotechnology, CAS Research/Education, Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing 100190, P. R. China ‡ School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, P. R. China § College of Science, Hunan Agricultural University, Changsha 410128, P. R. China S Supporting Information *

ABSTRACT: The poor contact between the solid-state electrolyte and cathode materials leads to a high interfacial resistance, severely limiting the rate capability of solid Li metal batteries. Herein, an integrative battery design is introduced with a gradiently polymerized solid electrolyte (GPSE), a microchannel current collector array, and nanosized cathode particles. An in situ formed GPSE encapsulates cathode nanoparticles in the microchannel with ductile inclusions to lower the interfacial impedance, and the stiff surface layer of GPSE toward anode suppresses the Li dendrite growth. The Li metal batteries based on GPSE and the Li-free hydrogenated V2O5 (V2O5−H) cathode exhibit an outstanding high rate response of up to 5 C (the capacity ratio of 5 C/1 C is 90.3%) and an ultralow capacity fade rate of 0.07% per cycle over 300 cycles. The other Li-containing cathodes such as LiFePO4 and LiNi0.5Mn0.3Co0.2O2 can also operate effectively at the rates of 5 and 2 C, respectively. Such an ingenious design may provide new insights into other solid metal batteries through an interfacial engineering manipulation at the micro- and nanolevel. KEYWORDS: allied micro-array, cathode design, gradient polymerization, interface modification, solid-state electrolyte

1. INTRODUCTION The pressing demand for high energy density storage devices has revived metallic lithium as anodes1−4 because of its highest theoretical specific capacity (3860 mA h g−1 or 2061 mA h cm−3).5−7 However, the issues of lithium dendrite growth in the Li metal batteries have provoked research studies on solidstate electrolytes (SSEs) to solve the hidden danger.8,9 Many of the advances in the protection of Li metal anodes from dendrites have been achieved using SSEs.10−12 These advancements in SSE technology have revolutionized the safety and stability in solid Li metal batteries.13−17 However, the high interfacial resistance between the cathode materials and the SSE has seriously hindered the exertion of the cycle performance and charge−discharge rates.18,19 A structural homogeneous SSE satisfies the demand for the inhibition of Li dendrites with high mechanical strength,20,21 yet causing restricted figurability and poor contacts with the cathode materials.22 The improvement of cycling safety by using SSE is at the expense of sacrificing the advantages of conventional organic liquid electrolytes including high ionic conductivity and good wettability. Lots of approaches have been proposed to optimize interfacial contact and ion transportation, including minimizing the cathode material particle size to the nanoscale to increase the contact areas with SSE,23,24 artificially modifying © 2018 American Chemical Society

the layer between the cathode and SSE to convert the point contact into surface contact, and coating ionic liquids on the cathode surface to achieve a solid−liquid−solid interface structure.25−28 However, when the cathode area loading is higher,29 or in a situation of the electrolyte with poor wettability,30,31 the function of layer modifications would become very limited, with only a small fraction of the cathode contact being improved. The root causes of these problems remain unresolved, and the structure manipulation and exploration for cathode materials and the current collector as an integral,32−34 which are of great significance, to boost battery performance have been ignored.35 Herein, an integrative design strategy of Li metal battery which reconciles the stability and ionic conductivity is introduced (Figure 1). For the Li metal side, because of dendrite formation, a high ionic conductivity solid electrolyte with high mechanical strength is required to prevent dendriteinduced short circuits.36 For the cathode side, a good surface contact with active materials enables the reduction of high interfacial resistances and shortens the ion transport distance. Received: April 2, 2018 Accepted: May 2, 2018 Published: May 2, 2018 18005

DOI: 10.1021/acsami.8b05288 ACS Appl. Mater. Interfaces 2018, 10, 18005−18011

Research Article

ACS Applied Materials & Interfaces

Figure 1. Comparison of different electrolyte-based Li metal batteries and schematic design of GPSE formation in the Al-AMC architecture. (a) Li dendrite growth in a Li metal battery using a liquid electrolyte may cause short circuit and safety issues. (b) Poor contacts between SSE and cathode materials lead to a high interfacial impedance in a solid Li metal battery. (c) GPSE constrains the Li dendrite and improves contacts with the electrodes via a stiff surface on the anode side and ductile inclusions on the cathode side. (d) Formation principle of GPSE. After UV curing, the GPSE reveals a high DP on the surface of Al-AMC (anode side) and a low DP inside the channels (cathode side) because of uneven light distribution. precursor of the electrolyte took the gaps’ space and made contact directly with each particle. After curing for 5 min, the liquid precursor transformed into a solid state and formed in situ with gradient DP. The batteries based on LiNi0.5Mn0.3Co0.2O2 (NCM523) and LiFePO4 (LFP) commercial cathode and GPSE were assembled by using the same method. The conventional curing solid electrolyte (CCSE) was acquired by evenly spreading the same amount of liquid precursor on the surface of Li foil and then directly curing the precursor with the same experimental conditions as that for GPSE. The explosion time, the UV light intensity, irradiation height, and all the other experimental elements were the same with the synthesis of GPSE. After polymerization, a uniform layer was formed on the surface of the Li foil, and the solid Li metal battery with CCSE was assembled without the polymerization gradient as a contrast. 2.2. Characterization. The X-ray diffraction (XRD) profiles of the as-obtained samples were obtained using a D/max 2500 X-ray diffractometer (Rigaku) with Cu Kα radiation (λ = 1.5418 Å) operated at 40 kV and 200 mA using a continuous scanning mode at 2° min−1 over the 2θ range of 10−70°. The Raman spectra were collected with a laser wavelength of 532 nm. The scanning electron microscopy (SEM) images and the corresponding electron probe microanalysis (EPMA) images were obtained with field emission SEM (JEOL 6701F) and EPMA (1720). The high-resolution transmission electron microscopy images and the linear scanning curves were obtained on a transmission electron microscope (TEM, JEM 2100F) with an accelerating voltage of 200 kV. X-ray photoelectron spectroscopy (XPS) of the samples were conducted on an ESCALab 250Xi (Thermo Scientific) spectrometer equipped with an Al Kα achromatic X-ray source. The binding energies of all elements were calibrated with respect to carbon (284.6 eV) and the XPS peaks were deconvoluted by the Avantage software. An atomic force microscopy (AFM) system (Bruker Multimode 8 with a Nanoscope V controller) in an Ar-filled glovebox was employed to measure the morphology and adhesion force for the GPSE surface. 2.3. Electrochemistry. The CR2032-type coin cells were assembled in the Ar-filled glovebox (H2O, O2 < 0.1 ppm). The loading of active materials was about 1.5 mg cm−2. All the coin cells were assembled using a hollow Celgard separator as the spacer (Φ 10 mm) for the sake of avoiding short circuit. Cyclic voltammetry was carried out on a ParSTAT MC electrochemical workstation (Prince-

To realize this purpose, a UV light-triggered gradiently polymerized solid electrolyte (GPSE) with a solid stiff surface on the anode side and ductile inclusions on the cathode side is formed in situ. The uniform layer with a high degree of polymerization (DP) provides mechanical stability to inhibit Li dendrites, and the inclusions with a gradiently descending DP on the cathode side improve the interface contact, which reconciles the demand of mechanical properties and interface modification for high-rate solid Li metal batteries.

2. EXPERIMENTAL SECTION 2.1. Materials Synthesis. The hollow V2O5 nanospheres were obtained from a previous report.37 The V2O5−H nanospheres were obtained by H2 thermal treatment at 200 °C for 2 h. The aluminous current collector with allied microchannel (Al-AMC) was obtained by the laser microprocessing system from Shanghai Fermi Laser Technology with a pore diameter of 15 μm, a pore depth of 80 μm, and a space of 10 μm; the diameter of AL-AMC was 1 cm and the thickness was about 100 μm. The GPSE was prepared in a dry room with the dew temperature below −70 °C. The V2O5−H nanospheres, Super P, and poly(vinyl difluoride) (Aldrich) were mixed to obtain a slurry in N-methylpyrrolidone with a weight ratio of 8:1:1. The slurry was uniformly poured on the Al-AMC and then transferred to a highpressure reactor. After applying 5 M Pa N2 atmosphere and being kept for 30 min, the slurry was compressed into the Al-AMC. Then, the AlAMC loaded with V2O5−H was dried in a vacuum chamber at 80 °C for 12 h. The electrolyte we used in this work was reported from one of our group’s previous report38 which integrates high mechanical strength (ca. 12 GPa) to suppress the dendrite growth and a high room-temperature ionic conductance (0.22 mS cm−1) that can operate effectively within 4.5 V versus Li+/Li. To achieve a gradient polymerization degree, the precursor was dropwise added onto the surface of the Al-AMC loaded with V2O5−H nanospheres. The cathode can only be perfused in the channels when it mixed with N-methyl-2-pyrrolidone (NMP) to attain a slurry state to maintain the mobility. After drying, the NMP was volatilized and the space it took transform into the gaps between the channel wall and the particles. These gaps are very important because in the next step, the 18006

DOI: 10.1021/acsami.8b05288 ACS Appl. Mater. Interfaces 2018, 10, 18005−18011

Research Article

ACS Applied Materials & Interfaces ton) at 60 °C. The galvanostatic tests were carried out using a LAND cycler (Wuhan Kingnuo Electronic Co., China) at 60 °C.

density areas. The simulation results are in good agreement with the experimental design. The fluorescence imaging experiments are carried out to testify the distribution of GPSE. The precursor of GPSE (labeled by fluorescein isothiocyanate) presents good liquidity that can easily penetrate the microchannels (Figure 3b). After photopolymerization, the cross section of the fluorescence image shows that the GPSE with a high DP forms a uniform layer above the Al-AMC and a conical structure inside the channel. As the intensity of UV light decreases sharply with the depth incensement inside the channel, a low DP GPSE is formed which can be washed away by ethanol with no appearance of fluorescence (Figure 3c). The in situ formed GPSE has a distinct variation of polymerization degree which agrees with the COMSOL simulation results. Furthermore, the AFM images of three-dimensional (3D) adhesion force mapping (Figure 3d,e) and the optical photographs (Figure S2) show that the adhesion force of GPSE dramatically decreases within the channel. However, when the probe moves to the uniform layer above the Al-AMC, the adhesion force tends to be constant. The variation tendency of the adhesion force is consistent with the simulation results and the fluorescence phenomenon. All the results confirm that we have successfully synthesized multifunctional GPSE with construction-regulated UV light-triggered polymerization. The hollow hydrogenated vanadium pentoxide (V2O5−H) nanospheres were synthesized through a solvothermal method as model cathode materials. The TEM image and the line scanning (Figures 4a and S3) test show the void space in hollow particles, which improves the particles’ ability to withstand the cyclic changes in volume and increases the long-term stability.39 After H2 thermal treatment,40 oxygen vacancies at the O (II) sites have been produced in the hollow V2O5−H nanospheres to increase the Li+ diffusion rate.41 XPS reveals that a weak peak at 515.59 eV ascribed to V4+ is observed in addition to the strong peak at 516.96 eV attributed to V 2p3/2 from V5+ (Figures 4b and S4),42 and the XRD patterns (Supporting Information Figure S5a,b) and Raman spectra (Figure S6a,b) are also used to testify the existence of the oxygen vacancies.43 The SEM (Figure 4c−e) and the EPMA (Figure S7a,b) images show that the V2O5−H nanospheres are successfully perfused into the microchannels. The other nanosized cathode particles including NCM523 and LFP (Figure S8) are also utilized with the same method in this system to show that the developed strategy is widely applied. It should be noted that the cathode materials with a nanosized structure are significant and favorable for perfusion into the channels of Al-AMC. The low DP inclusions and cathode materials are firmly sealed inside each microchannel to form a stable interfacial structure after polymerization. The thickness of the high DP layer above the Al-AMC is about 20 μm (Figure 4f). A smooth surface of GPSE is shown by the SEM and AFM morphologies (Figure 4g,h) with a high mechanical strength of 9.8 G Pa (Figure S9). Such an in situ formed GPSE is conductive to lower the interface impedance and release the rate capacity and cycling stability. To further ascertain the superiority of GPSE and the micro-/ nanostructured cathode array in liberating the discharging capability of the nanosized cathode materials, the Li metal batteries with CCSE without Al-AMC array have been fabricated as contrasts, and the discharging specific capacity shows only 129 and 107.5 mA h g−1 at 1 and 5 C for V2O5−H, 128.7 and 27.9 mA h g−1 at 1 and 5 C for LFP, 149.7 and 47.4

3. RESULTS AND DISCUSSION To implement the proposed strategy, an aluminous current collector with allied microchannel (Al-AMC) (Figure S1) is synthesized through laser drilling technology. The Al-AMC not only provides space for the storage of the positive electrode material, but also regulates the polymerization degree by controlling the UV light distribution. The cathode nanoparticles are in advance embedded into the microchannels by applying 5 M Pa N2 (see details in the Materials Synthesis section). The GPSE precursor was dropwise added on the cathode to fill the gaps between the cathode materials and the microchannel. After polymerization, the ductile inclusions and the cathode nanoparticles with high specific surface area are steadily enclosed inside the channel which largely increased the overall safety and stability with a sharply reduced interfacial resistance. Meanwhile, a stiff surface layer of GPSE on the array is formed to inhibit the dendrite growth. This integrative battery architecture (Figure 2) exploits the advantage of the

Figure 2. Schematic illustration of preparation of a GPSE-based Li metal battery. The Al-AMC is manufactured by laser drilling technology. The slurry containing cathode nanoparticles was poured on the Al-AMC, and high-pressure infusion was carried out by applying 5 M Pa N2. The GPSE was in situ formed by UV curing, and a scheme of Li+ transportation for GPSE-encapsulated cathode materials in the Al-AMC is presented.

cathode nanoparticles with the cooperation of GPSE and ALAMC, which are the three indispensable elements in achieving enhanced rate capacities and reduced interfacial resistance. The COMSOL Multiphysics numerical analysis has been carried out to simulate the UV light intensity distribution in the GPSE precursor-loaded Al-AMC system when the polymerization reaction occurs (Figure 3a). The color map represents the energy density of UV light, which shows that the light density is concentrated on the surface layer of the liquid GPSE precursor and the conical part inside the channels because of structure regulation. With an equal reaction time, more photoinitiators crack into the free radicals in the high light 18007

DOI: 10.1021/acsami.8b05288 ACS Appl. Mater. Interfaces 2018, 10, 18005−18011

Research Article

ACS Applied Materials & Interfaces

Figure 3. Structure simulation and characterization of GPSE. (a) COMSOL simulation analysis for light distribution above and inside the Al-AMC; the color mapping represents the energy density of UV light. (b,c) Fluorescence images of FITC molecules in the GPSE before and after UV curing. (d) Schematic illustration for the scanning direction of the AFM probe. (e) 3D adhesion force mapping of the GPSE formed in the Al-AMC.

Figure 4. Characterization for the cathode- and GPSE-encapsulated Al-AMC. (a) TEM image and line scanning curves of V2O5−H nanospheres. (b) XPS spectrum of V element in the hollow V2O5−H nanospheres. (c) Top-view SEM image of the Al-AMC. (d,e) Top-view and cross-section-view SEM images of the Al-AMC after loading with V2O5−H. (f) Cross-section view of the Al-AMC and V2O5−H encapsulated by GPSE. (g,h) SEM and AFM topography images of the GPSE surface.

mA h g−1 at 0.2 and 2 C for NCM523 (Figure 5a−f). Although the Li metal batteries based on GPSE and micro-/nanostructured cathode array show almost a constant overpotential in the first two cycles (Figure S10) and exhibit an outstanding rate performance with the speedup of Li+ transportation, the specific capacities are 139.2 and 125.9 mA h g−1 at 1 and 5 C for V2O5−H (1 C = 150 mA h g−1), 142.9 and 90.8 mA h g−1 at 1 and 5 C for LFP (1 C = 170 mA h g−1), and 155.9 and 97 mA h g−1 at 0.2 and 2 C for NCM523 (1 C = 200 mA h g−1), respectively. For the long-term cycling performance of the solid Li metal battery with GPSE and V2O5−H cathode, the capacity retention remains at 78% even after 300 cycling tests at 5 C with an ultralow long-term capacity fade rate of 0.07% per cycle (Figure 5g). Also, a specific capacity of 112.5 mA h g−1 is maintained at 1 C after 200 cycles for the full cells based on GPSE and V2O5−H, whereas the contrast battery with CCSE shows an obvious capacity degradation, with a specific capacity of only 102.6 mA h g−1 (Figure S11). The interfacial resistances

of the V2O5−H cathode in a solid Li metal battery with CCSE dramatically increase on the cathode side after 200 cycles at 1 C compared with the solid Li metal battery with GPSE (Figure S12a−c). Obviously, the GPSE facilitates the migration of lithium ions as the in situ photopolymerization eliminates the gaps between the cathode particles and the solid electrolyte with a high Li+ transporting speed, leading to significantly reduced interfacial resistances on the cathode side (Table S1). After 300 cycling tests, a smooth surface of Li metal is observed after the battery is disassembled (Figure S13). Also, the pouch cells work normally even after being cut (Figure 5h). Before and after the bending tests, the pouch cell can still light the LED devices. The above results manifest that such a battery design owns remarkable safety and flexibility.

4. CONCLUSION In this work, the design strategy that combines a high mechanical strength layer to suppress Li dendrites and ductile inclusions on the micro-/nanostructured cathode side to realize 18008

DOI: 10.1021/acsami.8b05288 ACS Appl. Mater. Interfaces 2018, 10, 18005−18011

Research Article

ACS Applied Materials & Interfaces

Figure 5. Electrochemical performances of solid Li metal batteries with GPSE. (a,b) Rate capabilities of the NCM523 cathode and the corresponding galvanostatic discharging/charging profiles. (c,d) Rate capabilities of the LFePO4 cathode and the corresponding galvanostatic discharging/charging profiles. (e,f) Rate capabilities of the V2O5−H cathode and the corresponding galvanostatic discharging/charging profiles. (g) Cycling performances of V2O5−H at the rate of 5 C. (h) The pouch cell with the V2O5−H cathode and GPSE can still lighten the LED devices before and after the bending tests and even after being cut.

■

interface modification is put forward via structure-regulated photopolymerization. The microchannel cathode array provides improved safety and stability with the encapsulated nanoparticles and low DP solid electrolyte. The GPSE-based Li metal battery exhibits an excellent rate capability and a longterm cycling stability at a high rate. This interfacial engineering endows a good contact between the cathode materials and GPSE and a superior ion transportation compared with the conventional coating configuration in solid Li metal batteries. This design strategy will inspire a deep comprehension of interface regulation and integral structure design for other electrochemical energy storage systems at the micro- and nanolevel.

ASSOCIATED CONTENT

S Supporting Information *

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acsami.8b05288. SEM image of Al-AMC, optical photograph of the AFM probe position, photographs and morphology evolution of V2O5, XPS spectrum of hollow V2O5 microspheres, XRD patterns, Raman peaks, cross-section view of EPMA images, SEM images of two Li-contained cathodes, CV curves of GPSE Li metal batteries, cycling performance, electrochemical impedance profiles, SEM image of the Li metal anode, and interfacial resistances (PDF)

■

AUTHOR INFORMATION

Corresponding Authors

*E-mail: [email protected] (C.R.-W.). 18009

DOI: 10.1021/acsami.8b05288 ACS Appl. Mater. Interfaces 2018, 10, 18005−18011

Research Article

ACS Applied Materials & Interfaces *E-mail: [email protected]. Phone/Fax: (+86)-10-82617069 (Y.-G. G.).

(15) Cheng, X.-B.; Zhang, R.; Zhao, C.-Z.; Wei, F.; Zhang, J.-G.; Zhang, Q. A Review of Solid Electrolyte Interphases on Lithium Metal Anode. Adv. Sci. 2016, 3, 1500213. (16) Mauger, A.; Armand, M.; Julien, C. M.; Zaghib, K. Challenges and Issues Facing Lithium Metal for Solid-State Rechargeable Batteries. J. Power Sources 2017, 353, 333−342. (17) Hovington, P.; Lagacé, M.; Guerfi, A.; Bouchard, P.; Mauger, A.; Julien, C. M.; Armand, M.; Zaghib, K. New Lithium Metal Polymer Solid State Battery for an Ultrahigh Energy: Nano C-LiFePO4 versus Nano Li1.2V3O8. Nano Lett. 2015, 15, 2671−2678. (18) Sun, Y.; Liu, N.; Cui, Y. Promises and Challenges of Nanomaterials for Lithium-Based Rechargeable Batteries. Nat. Energy 2016, 1, 16071. (19) Tenhaeff, W. E.; Perry, K. A.; Dudney, N. J. Impedance Characterization of Li Ion Transport at the Interface between Laminated Ceramic and Polymeric Electrolytes. J. Electrochem. Soc. 2012, 159, A2118−A2123. (20) Tikekar, M. D.; Choudhury, S.; Tu, Z.; Archer, L. A. Design Principles for Electrolytes and Interfaces for Stable Lithium-Metal Batteries. Nat. Energy 2016, 1, 16114. (21) Luo, W.; Gong, Y.; Zhu, Y.; Fu, K. K.; Dai, J.; Lacey, S. D.; Wang, C.; Liu, B.; Han, X.; Mo, Y.; Wachsman, E. D.; Hu, L. Transition from Superlithiophobicity to Superlithiophilicity of Garnet Solid-State Electrolyte. J. Am. Chem. Soc. 2016, 138, 12258−12262. (22) Aricò, A. S.; Bruce, P.; Scrosati, B.; Tarascon, J.-M.; Van Schalkwijk, W. Nanostructured Materials for Advanced Energy Conversion and Storage Devices. Nat. Mater. 2005, 4, 366−377. (23) Groenendaal, L.; Jonas, F.; Freitag, D.; Pielartzik, H.; Reynolds, J. R. Poly(3,4-ethylenedioxythiophene) and its Derivatives: Past, Present, and Future. Adv. Mater. 2000, 12, 481−494. (24) Hayashi, A.; Nishio, Y.; Kitaura, H.; Tatsumisago, M. Novel Technique to Form Electrode-Electrolyte Nanointerface in All-SolidState Rechargeable Lithium Batteries. Electrochem. Commun. 2008, 10, 1860−1863. (25) Tan, R.; Yang, J.; Zheng, J.; Wang, K.; Lin, L.; Ji, S.; Liu, J.; Pan, F. Fast Rechargeable All-Solid-State Lithium Ion Batteries with High Capacity Based on Nano-Sized Li2FeSiO4 Cathode by Tuning Temperature. Nano Energy 2015, 16, 112−121. (26) Kim, J.-K.; Lim, Y. J.; Kim, H.; Cho, G.-B.; Kim, Y. A Hybrid Solid Electrolyte for Flexible Solid-State Sodium Batteries. Energy Environ. Sci. 2015, 8, 3589−3596. (27) Vogl, T.; Vaalma, C.; Buchholz, D.; Secchiaroli, M.; Marassi, R.; Passerini, S.; Balducci, A. The Use of Protic Ionic Liquids with Cathodes for Sodium-Ion Batteries. J. Mater. Chem. A 2016, 4, 10472− 10478. (28) Li, M.; Yang, L.; Fang, S.; Dong, S.; Hirano, S.-i.; Tachibana, K. Polymer Electrolytes Containing Guanidinium-Based Polymeric Ionic Liquids for Rechargeable Lithium Batteries. J. Power Sources 2011, 196, 8662−8668. (29) Gao, H.; Xue, L.; Xin, S.; Park, K.; Goodenough, J. B. A PlasticCrystal Electrolyte Interphase for All-Solid-State Sodium Batteries. Angew. Chem., Int. Ed. 2017, 56, 5541−5545. (30) Delcheva, I.; Ralston, J.; Beattie, D. A.; Krasowska, M. Static and Dynamic Wetting Behaviour of Ionic Liquids. Adv. Colloid Interface Sci. 2015, 222, 162−171. (31) MacFarlane, D. R.; Tachikawa, N.; Forsyth, M.; Pringle, J. M.; Howlett, P. C.; Elliott, G. D.; Davis, J. H., Jr.; Watanabe, M.; Simon, P.; Angell, C. A. Energy Applications of Ionic Liquids. Energy Environ. Sci. 2014, 7, 232−250. (32) Liu, K.; Pei, A.; Lee, H. R.; Kong, B.; Liu, N.; Lin, D.; Liu, Y.; Liu, C.; Hsu, P.-c.; Bao, Z.; Cui, Y. Lithium Metal Anodes with an Adaptive “Solid-Liquid” Interfacial Protective Layer. J. Am. Chem. Soc. 2017, 139, 4815−4820. (33) Wang, H.; Matsui, M.; Kuwata, H.; Sonoki, H.; Matsuda, Y.; Shang, X.; Takeda, Y.; Yamamoto, O.; Imanishi, N. A Reversible Dendrite-Free High-Areal-Capacity Lithium Metal Electrode. Nat. Commun. 2017, 8, 15106. (34) Yang, C.-P.; Yin, Y.-X.; Zhang, S.-F.; Li, N.-W.; Guo, Y.-G. Accommodating Lithium into 3D Current Collectors with a

ORCID

Xian-Xiang Zeng: 0000-0001-7662-2349 Ji-Lie Shi: 0000-0003-2887-2620 Tai-shan Wang: 0000-0003-1834-3610 Chun-Ru Wang: 0000-0001-7984-6639 Yu-Guo Guo: 0000-0003-0322-8476 Notes

The authors declare no competing financial interest.

■

ACKNOWLEDGMENTS This wok was supported by the Basic Science Center Project of National Natural Science Foundation of China under grant No. 51788104, the National Key R&D Program of China (Grant No. 2016YFA0202500), the National Natural Science Foundation of China (21773264, 51672281) and the “Transformational Technologies for Clean Energy and Demonstration”, Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA 21070300).

■

REFERENCES

(1) Evarts, E. C. Lithium batteries To the Limits of Lithium. Nature 2015, 526, S93−S95. (2) Li, G.; Gao, Y.; He, X.; Huang, Q.; Chen, S.; Kim, S. H.; Wang, D. Organosulfide-Plasticized Solid-Electrolyte Interphase Layer Enables Stable Lithium Metal Anodes for Long-Cycle Lithium-Sulfur Batteries. Nat. Commun. 2017, 8, 850. (3) Zheng, J.; Engelhard, M. H.; Mei, D.; Jiao, S.; Polzin, B. J.; Zhang, J.-G.; Xu, W. Electrolyte Additive Enabled Fast Charging and Stable Cycling Lithium Metal Batteries. Nat. Energy 2017, 2, 17012. (4) Bouchet, R. Batteries: A Stable Lithium Metal Interface. Nat. Nanotechnol. 2014, 9, 572−573. (5) Xu, W.; Wang, J.; Ding, F.; Chen, X.; Nasybulin, E.; Zhang, Y.; Zhang, J.-G. Lithium Metal Anodes for Rechargeable Batteries. Energy Environ. Sci. 2014, 7, 513−537. (6) Ye, H.; Xin, S.; Yin, Y.-X.; Li, J.-Y.; Guo, Y.-G.; Wan, L.-J. Stable Li Plating/Stripping Electrochemistry Realized by a Hybrid Li Reservoir in Spherical Carbon Granules with 3D Conducting Skeletons. J. Am. Chem. Soc. 2017, 139, 5916−5922. (7) Lin, D.; Liu, Y.; Cui, Y. Reviving the Lithium Metal Anode for High-Energy Batteries. Nat. Nanotechnol. 2017, 12, 194−206. (8) Zhang, X.-Q.; Chen, X.; Xu, R.; Cheng, X.-B.; Peng, H.-J.; Zhang, R.; Huang, J.-Q.; Zhang, Q. Columnar Lithium Metal Anodes. Angew. Chem., Int. Ed. 2017, 56, 14207−14211. (9) Janek, J.; Zeier, W. G. A Solid Future for Battery Development. Nat. Energy 2016, 1, 16141. (10) Zhao, C.-Z.; Zhang, X.-Q.; Cheng, X.-B.; Zhang, R.; Xu, R.; Chen, P.-Y.; Peng, H.-J.; Huang, J.-Q.; Zhang, Q. An AnionImmobilized Composite Electrolyte for Dendrite-Free Lithium Metal Anodes. Proc. Natl. Acad. Sci. U.S.A. 2017, 114, 11069−11074. (11) Duan, H.; Yin, Y.-X.; Zeng, X.-X.; Li, J.-Y.; Shi, J.-L.; Shi, Y.; Wen, R.; Guo, Y.-G.; Wan, L.-J. In-Situ Plasticized Polymer Electrolyte with Double-Network for Flexible Solid-State Lithium-Metal Batteries. Energy Environ. Sci. 2018, 10, 85−91. (12) Cui, Y.; Liang, X.; Chai, J.; Cui, Z.; Wang, Q.; He, W.; Liu, X.; Liu, Z.; Cui, G.; Feng, J. High Performance Solid Polymer Electrolytes for Rechargeable Batteries: A Self-Catalyzed Strategy toward Facile Synthesis. Adv. Sci. 2017, 4, 1700174. (13) Li, N.-W.; Yin, Y.-X.; Yang, C.-P.; Guo, Y.-G. An Artificial Solid Electrolyte Interphase Layer for Stable Lithium Metal Anodes. Adv. Mater. 2016, 28, 1853−1858. (14) Yang, C.; Fu, K.; Zhang, Y.; Hitz, E.; Hu, L. Protected LithiumMetal Anodes in Batteries: From Liquid to Solid. Adv. Mater. 2017, 29, 1701169. 18010

DOI: 10.1021/acsami.8b05288 ACS Appl. Mater. Interfaces 2018, 10, 18005−18011

Research Article

ACS Applied Materials & Interfaces Submicron Skeleton towards Long-Life Lithium Metal Anodes. Nat. Commun. 2015, 6, 8058. (35) Wang, Y.; Cao, G. Developments in Nanostructured Cathode Materials for High-Performance Lithium-Ion Batteries. Adv. Mater. 2008, 20, 2251−2269. (36) Stone, G. M.; Mullin, S. A.; Teran, A. A.; Hallinan, D. T., Jr.; Minor, A. M.; Hexemer, A.; Balsara, N. P. Resolution of the Modulus versus Adhesion Dilemma in Solid Polymer Electrolytes for Rechargeable Lithium Metal Batteries. J. Electrochem. Soc. 2012, 159, A222−A227. (37) Pan, A.; Wu, H. B.; Yu, L.; Lou, X. W. D. Template-Free Synthesis of VO2 Hollow Microspheres with Various Interiors and Their Conversion into V2O5 for Lithium-Ion Batteries. Angew. Chem., Int. Ed. 2013, 52, 2226−2230. (38) Zeng, X.-X.; Yin, Y.-X.; Li, N.-W.; Du, W.-C.; Guo, Y.-G.; Wan, L.-J. Reshaping Lithium Plating/Stripping Behavior via Bifunctional Polymer Electrolyte for Room-Temperature Solid Li Metal Batteries. J. Am. Chem. Soc. 2016, 138, 15825−15828. (39) Lou, X. W.; Archer, L. A.; Yang, Z. Hollow Micro-/ Nanostructures: Synthesis and Applications. Adv. Mater. 2008, 20, 3987−4019. (40) Peng, X.; Zhang, X.; Wang, L.; Hu, L.; Cheng, S. H.-S.; Huang, C.; Gao, B.; Ma, F.; Huo, K.; Chu, P. K. Hydrogenated V2O5 Nanosheets for Superior Lithium Storage Properties. Adv. Funct. Mater. 2016, 26, 784−791. (41) Ma, W. Y.; Zhou, B.; Wang, J. F.; Zhang, X. D.; Jiang, Z. Y. Effect of Oxygen Vacancy on Li-Ion Diffusion in a V2O5 Cathode: a First-Principles Study. J. Phys. D: Appl. Phys. 2013, 46, 105306. (42) Goclon, J.; Grybos, R.; Witko, M.; Hafner, J. Oxygen Vacancy Formation on Clean and Hydroxylated Low-Index V2O5 Surfaces: A Density Functional Investigation. Phys. Rev. B: Condens. Matter Mater. Phys. 2009, 79, 075439. (43) Hermann, K.; Chakrabarti, A.; Druzinic, R.; Witko, M. Hydrogen Assisted Oxygen Desorption from the V2O5 (010). Phys. Status Solidi A 2000, 173, 195.

18011

DOI: 10.1021/acsami.8b05288 ACS Appl. Mater. Interfaces 2018, 10, 18005−18011