Surface Restraint Synthesis of an Organic–Inorganic Hybrid Layer for

Feb 20, 2019 - Surface Restraint Synthesis of an Organic–Inorganic Hybrid Layer for Dendrite-Free Lithium Metal Anode. Jijin Yang‡ , Cejun Hu‡ ,...
0 downloads 0 Views 872KB Size
Subscriber access provided by University of Glasgow Library

Letter

Surface Restraint Synthesis of an Organic-inorganic Hybrid Layer for Dendrite Free Lithium Metal Anode Jijin Yang, Cejun Hu, Yin Jia, Yingchun Pang, Li Wang, Wen Liu, and Xiaoming Sun ACS Appl. Mater. Interfaces, Just Accepted Manuscript • DOI: 10.1021/acsami.9b00507 • Publication Date (Web): 20 Feb 2019 Downloaded from http://pubs.acs.org on February 20, 2019

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 22 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Applied Materials & Interfaces

Surface Restraint Synthesis of an Organic-inorganic Hybrid Layer for Dendrite Free Lithium Metal Anode Jijin Yang1,‡, Cejun Hu1,‡, Yin Jia‡, Yingchun Pang*,‡, Li Wang*,§, Wen Liu*,‡ and Xiaoming Sun‡ ‡: College of Energy & College of Science, State Key Laboratory of Chemical Resource Engineering, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China §: Institute of Nuclear & New Energy Technology, Tsinghua University, Beijing 100084, China 1: These authors contributed equally to this work E-mail: [email protected]; [email protected]; [email protected];

ABSTRACT

Li metal is considered to be the most attractive anode for next-generation batteries because of its high specific capacity and low reduction potential. However, uncontrolled Li dendrite growth and low coulombic efficiency cause severe capacity decay and safety issues. Here we propose a LiCl contained inorganic-organic hybrid layer on Li metal surface by a surface restraint

ACS Paragon Plus Environment

1

ACS Applied Materials & Interfaces 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 2 of 22

dehalogenation reaction, which is highly uniform and features lithiophilic property as well as high ionic conductivity that can inhibit Li dendrite growth effectively. Consequently, the surface protected Li metal electrodes enable Li | Li symmetric cells to maintain a stable and low overpotential of 20 mV at a current density of 1 mA cm-2 after cycling over 3000 h, and enable Li | LiFePO4 pouch cell to decay only 0.05% in capacity per cycle at 5.0 C for 500 cycles, indicating excellent cycle stability and high rate capability. This work offers a simple and facile method to protect Li metal anode and promise a potential direction for industrialization of Li metal batteries.

KEYWORDS: Lithium metal anode, Dendrite inhibition, lithium metal batteries, Surface restraint dehalogenation reaction, Organic-inorganic composite layer 1. INTRODUCTION Nowadays, lithium-ion batteries (LIBs) have been widely used in portable electronics such as laptops, mobile phones, digital cameras, and etc.,1 and which are also starting into vehicle industry and grid energy storage. However, current LIBs based on the intercalation chemistry have limited energy density, that hinders their further development especially in large scale applications. Some novel battery chemistry, such as Li metal battery, lithium-sulfur battery, and lithium-air/oxygen battery, are promising to address the energy anxiety2. In all of these breakthroughs, lithium metal anode is employed because of its low reduction potential (−3.04 V vs. standard hydrogen electrode) and extraordinary high theoretical specific capacity (3,860 mAh g−1).3 However, the uncontrolled dendrite growth and continuous SEI formation cause severe capacity decay and inner short circuit of batteries,3-4 which substantially hinder the practical application of those novel batteries.

ACS Paragon Plus Environment

2

Page 3 of 22 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Applied Materials & Interfaces

The plating and striping of Li metal anode in battery cycling is influenced mainly by the surface chemistry and physics. In general, the uneven solid electrolyte interphase (SEI) formed on the surface of Li metal surface leads to uneven Li metal deposition. The slightly raised protuberance induces higher charge density and shorter pathway of Li+ migration than flat part and pits, which provides preferable and fast sites for lithium plating thus ramifies growth of Li dendrites.5 Meanwhile, huge volumetric changes during the Li deposition process cause break of SEI layer and exposure of fresh Li metal. The dendrite growth and repeated SEI formation with rapid consumption of the electrolyte,6-7 which is the main reason of low coulombic efficiency and battery failure (Figure 1a). 8 To address this issue, researchers explored various approaches9-10, including employing solid electrolyte,11-14 regulating nucleation of Li,15-22 surface protection,23-28 and etc. Solid electrolyte could prevent lithium dendrite penetration and may avoid firing after a short circuit.29 Besides poor ionic conductivity and high interfacial resistance,30 the big challenge that the rigid interface surface between solid state electrolyte and lithium metal cannot accommodate huge volume change of lithium metal during charge and discharge31 will bother the development of lithium metal batteries for a long time. Regulating lithium nucleation through an artificial surface proactive layer or a lithophilic substance are proved to be effective to enhance lithium platingstriping reversibility while bring little change to current battery industry. In addition, Ocontained groups (-OH, -COOH and –SO3H),32 lithophilic metal (Ag, Au)15 and lithium halides24 have demonstrated their effectiveness in regulating lithium plating. For instance, the 3D carbon fiber treated by acid32 and decorated by Ag nanoparticles33 induced dendrite free Li metal deposition even with a large area capacity. Lithium halide especially lithium fluoride (LiF) adjusted Li+ ion flux due to its high surface diffusivity for Li ions.34 Zhang and co-workers

ACS Paragon Plus Environment

3

ACS Applied Materials & Interfaces 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 4 of 22

realized the orderly Li columnar deposition, indicating the powerful function of lithium halide in guiding Li nucleation.18 In terms of surface protection, on one hand, a flexible coating layer that can provide an adaptive and dynamic uniform surface is necessary to tolerate volume change, and organic materials containing cross-linked chains are good choices.35-36 On the other hand, a protective layer with a high modulus helps to sustain the stress avoiding Li dendrite growth.25 Thus, some lithium salt contained interlayers with high flexibility and high modulus were fabricated to protecting Li metal anode.37-38 In addition, surface layer with high Li+ ionsconductivity has also been structured with metal chloride in it.39 On this regard, a brilliant surface layer with advantages of both high strength and lithophilic properties is highly desired to achieve dendrite free lithium metal deposition .40-41 Herein, we propose a LiCl-containing organic-inorganic hybrid layer (OIHL) on Li metal surface to settle the dendrite problem, which is fabricated by an in-situ surface restraint dehalogenation reaction to realizing uniform distribution of LiCl nanoparticles in organic matrix inside the surface layer and tight adherence between lithium metal and the surface layer . The soft polymer metrix with flexible properties adapts well with the natively uneven surface of lithium metal electrode, and adjusts to volume changes during cycling. Meanwhile, inorganic LiCl particles contribute to mechanic strength, ion conductivity and regulation of uneven Li+ flux, inducing homogenous Li deposition. Based on the OIHL-Li, symmetric Li | Li cells can stably cycle over 3000 h at the current density of 1.0 mA cm-2 without dendrite growth, and Li | LFP pouch cell shows 4 times longer life than normal Li | LFP pouch cell and its capacity attenuation per cycle is only 0.05% at 5.0 C. 2. RESULTS AND DISCUSSION 2.1 Material synthesis and characterization

ACS Paragon Plus Environment

4

Page 5 of 22 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Applied Materials & Interfaces

The surface organic-inorganic hybrid layer was in-situ synthesized on lithium metal surface, where LiOH and Li2CO3 species formed naturally due to unavoidable exposure to oxygen and moisture, which can be used for dehalogenation of perchlorethylene (PCE). The OIHL could be obtained by dropping the PCE solution on Li metal surface and spreading it using doctor blade. With the flexible cross-linked organic chains and homogeneously distributed LiCl nanoparticles, the OIHL inhibited lithium dendrite growth effectively (Figure 1b). The reaction mechanisms were proposed and shown in Figure S1a. The hydroxyls in LiOH could substitute parts of chlorine in PCE molecule and produce LiCl. Afterwards, the hydroxyl groups bonded with the double-bonded carbon and went through a series of chemical reactions, then formed oligomeric polyester chains and networks. Meanwhile, the trace amount of water plays an important role in the self-restraint reaction, which can corrode Li metal to form LiOH until the surface layer is dense enough that the raw material of C2Cl4 cannot reach the reaction interface. The surface products were characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) in Figure S1b and 2a. The characteristic peaks at 1619.91 cm-1 and 3426.25 cm-1 in FTIR are all corresponded to –COO– groups which are also the major organic component in the OIHL. In C 1s XPS spectra, three components at binding energy of 284.5, 286.4 and 289.8 eV can be observed, which can be assigned to C-C, C-O and O=C-O bonds respectively. The O=C-O species reflected by XPS analysis is in good agreement with FTIR data, further confirm the formation of polyester chains and networks. The organic component of polyester is flexible and enables the OIHL to adapt the volume fluctuation during cycling. The existence of LiCl was also demonstrated by Cl 2p XPS analysis with binding energy at 200.5 eV, as shown in Figure 2b. LiCl nanoparticles produced by the in-situ surface chemical reaction are homogeneously distributed among the OIHL, which provides a pathway for Li+

ACS Paragon Plus Environment

5

ACS Applied Materials & Interfaces 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 6 of 22

diffusion and induces uniformly Li deposition. The top-view SEM images of the pristine and surface protected Li metal foil are shown in Figure 2c. The morphology of Li metal surface kept almost unchanged after the surface chemical reaction and construction of the LiCl containing OIHL. As marked in the cross sectional SEM images (Figure 2f), the thickness of OIHL is about 12 μm. 2.2 Electrochemical performance Cyclic voltammogram of the pristine Li and OIHL-Li in the ether-based electrolyte (1M LiTFSI in 1:1 DME/DOL with 2% LiNO3) was measured and shown in Figure 3a. In the potential range of -0.5 to 3.0 V, the cell with pristine Li metal anode shows only two peaks at 0.35V and 0.3 V, which can be attributed to the redox of Li+/Li. Similarly, the cell with OIHL-Li foil exhibits the same redox peaks, which demonstrates that there is no other side reaction happened on the Li metal anode and OIHL is electrochemically stable in the ether-based electrolyte. Meanwhile, the OIHL surface owned the better ionic conductivity thus attribute to the higher current peak of OIHL-Li than pristine Li metal. As reported in previous researches, lithium halides such as LiF and LiCl help Li ions diffusion and decrease the surface resistance.18 Thus Li+ ions tend to transfer through the nearside of LiCl particles, which were interpreted as “lithiophilicity”. The same in Li | Cu systems, the increased surface ionic conductivity of the OIHL-Li can be also confirmed by the decreased voltage hysteresis as shown in Figure 3b. The voltage polarization between the charge and discharge curves depends heavily on the surface impedance, and the cell with OIHL-Li shows a lower polarization than the cell with pristine Li does. Furthermore, for the cell with OIHL-Li anode, the voltage polarization keeps stable after cycling, while that is increasing in the cell with pristine Li (Figure 3c). Similar tendency appeared on

ACS Paragon Plus Environment

6

Page 7 of 22 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Applied Materials & Interfaces

coulombic efficiency, which decrease after 300 cycles in Bare Li | Cu cells while it shows a hardly change (Figure S2). As the variation of voltage hysteresis and coulombic efficiency during cycling reflecting the change of interfacial impedance, it can be concluded that the surface state of OIHL-Li was more stable than that of pristine Li metal during cycling. Electrochemical impedance spectroscopy (EIS) was also measured to further understand the surface charge and Li+ ion transference (Figure 3d). The OIHL-Li shows a smaller surface resistance of 100 ohm comparing with 176 ohm of the pristine Li metal anode. From 1 cycle to 10 cycles, the interfacial impedance of the pristine Li metal anode increase 51 ohm while that of the surface protected Li metal anode is only 28.5 ohm. The slow increase of the interface impedance on the protected Li metal is owing to the dense and uniform OIHL which prevents the side reaction between the Li metal and electrolyte as well as suppresses thick SEI growth. Li | Li symmetric cells were fabricated to further evaluate the electrochemical performance of OIHL-Li anode. The discharge-charge curves at 1.0 and 2.0 mA cm−2 current densities with an areal capacity of 1 mAh cm−2 are shown in Figure 3e&3f, respectively. The pristine Li metal anode shows an increasing and large polarization when cycling at 1 mA cm-2 while the OIHL-Li anode exhibit a stable overvoltage of 20 mV over 3000 hours (1500 cycles). The increasing polarization of the pristine Li indicates continuous growth of SEI, which increased the interfacial impedance of the cells. When increasing the current density to 2.0 mA cm-2, Li | Li cell with pristine lithium metal anode occurred internal short circuit at 130 hours due to severe dendrite growth. In sharp contrast, the cell with the OIHL-Li anode kept small and stable over-voltage even after cycling 1200 hours (600 cycles).

2.3 Postdemn analysis of lithium metal anode

ACS Paragon Plus Environment

7

ACS Applied Materials & Interfaces 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 8 of 22

To directly evaluate the protective effect of the OIHL, the morphology of Li metal anode after cycling in Li|Cu cells were observed by SEM. As expected, large quantities of bulk dendrites and “dead Li” appear on the pristine Li foil surface (Figure 4a&4c), which is consistent with former reports.40, 42 The rugged surface would cause uneven Li+ distribution and induce catastrophic Li dendrite growth. However, in the presence of the OIHL, the Li anode maintains an extraordinarily smooth surface after 50 cycles (Figure 4b&4d). More importantly, after stripping a constant amount of Li (3 mAh cm-1, approximate 15 µm thickness of Li foil), the OIHL still keeps combining tightly with lithium metal below and without any pore on its surface (Figure S3a&b). This strong surface adhesion can be attributed to the chemical bonds formed during the surface synthesis, as well as the flexibility provided by the soft polymers. As demonstrated in Figure 4e, the purple part denotes the soft organic chains, and the pink particles mean the homogeneous spread LiCl particles. The in-situ fabricating reaction and flexible properties of OIHL attribute to an uncrack electrode surface. LiCl particles can serve as the ionic channels that enable the Li+ ions across the layer, and the OIHL inhibits dendrite growth and adapts well with the volume change during cycling. The surface chemistry of the OIHL-Li anode after the cycling test was further investigated by the XPS analysis, as shown in Figure 4f&4g. After 15 cycles, the C 1s XPS spectrum of bare Li can be deconvoluted to the peaks at 284.8, 286.2, 288.6 and 292.2 eV, which corresponding to the binding energy of C-C, C-O, C=O, and C-F respectively. Specifically, the peak of C=O located at 288.6 eV is the most common organic component in ordinary SEI layer. However, on the surface of OIHL-Li, the peak at 289.8 eV can be assigned to C=O binding of RO-COcomponent of the organic component in the OIHL (Figure 4f), demonstrating the heritage of components in SEI layer from the organic-inorganic coating layer before cycling (Figure 2a).

ACS Paragon Plus Environment

8

Page 9 of 22 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Applied Materials & Interfaces

Besides, the XPS Cl 2p spectra of the pristine Li and OIHL-Li anode after 15 cycles were presented in Figure 4g. The peak at 200.1 eV was identified as the characteristic binding energy of LiCl, which only appeared in the spectra of OIHL-Li. It shows that the LiCl nanoparticles in the OIHL retained after cycling, so it can continuously induce the uniform deposition of Li.

2.4 Full cell performance The application potential of the OIHL-Li anode was tested by Li|LiFePO4 (LFP) coin cells as well as pouch cells. Commercial Li metal belt was modified by a surface coating method, and then punched or cropped into suitable size for use as anodes in coin cells and pouch cells (Figure 5a), respectively. As shown in Figure S4a, the Bare Li | LFP cell in ether based electrolyte exhibits discharge capacity of 156.5 mAh g-1 at 1.0 C (170 mAh g-1) while the OIHL-Li | LFP cell delivers a higher discharge capacity of 164.8 mAh g-1, which is nearly approaching the theoretical capacity of LFP. The improvement of specific capacity is mainly attributed to the high ionic conductivity and stability of OIHL-Li, which shows low surface impedance thus leads to small over-potential and high capacity. Similarly, the OIHL-Li | LFP cells showed specific capacities of 153.2 and 145.6 mAh g-1 at 5.0 C, which is higher than Bare Li | LFP cells (Figure S4b). besides, OIHL-Li | LFP cell retained specific capacity of 145 mAh g-1 after 350 cycles at 1.0 C while the Bare Li | LFP cell only left 115 mAh g-1 after 300 cycles (Figure S5a), indicating that OIHL-Li | LFP cell has higher cycleability. When further increase discharge C-rate, the difference of cycling stability between these two electrodes was more obvious. OIHL-Li | LFP cells show only 0.05% capacity decay per cycle while pristine-Li | LFP cells show 0.1% capacity decay per cycle (Figure 5b). As reported, lithium dendrite grows severely at high current densities, the high capacity retention of OIHL-Li | LFP at high C-rates is owing to the stable surface and suppression of dendrite formation. To further confirm the protecting effect of the

ACS Paragon Plus Environment

9

ACS Applied Materials & Interfaces 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 10 of 22

OIHL, the cells using carbonate electrolyte was tested and shown in Figure 4b. The OIHL-Li anode stably cycled 200 times with a high capacity retention of 98%, suggesting that this OIHLLi anode can be compatible with the commercial electrolyte. Furthermore, OIHL-Li | LFP pouch cell also revealed brilliant cycling stability compared with LFP|Li pouch cell (Figure 5c). The cells were cycled in the C-rate order of 0.1, 0.2, 0.5 and 1.0 C. The initial capacity of OIHL-Li | LFP cell was 8.23 mAh, which converted into the specific capacity of 155.3 mAh g-1 that practically close to that of the coin cells. But the Bare Li | LFP cell showed an initial capacity of 7.64 mAh (153.5 mAh g-1) and rapid capacity decay during cycling. The rigorous capacity decay of Bare Li | LFP pouch cells is owing to large quantities of dendrite growth and Li metal pulverization in a large area of electrode. The OIHL-Li | LFP pouch cell not only exhibited an excellent cycling performance, but also had a stable discharge voltage, which can be reflected by powering 80 light-emitting diodes required power of 3.2 W (Figure 5c). Owing to the simplicity of our surface coating technology, Li metal foil can be uniformly protected with the OIHL even at large area, which is a vital factor in continuous industrial production. For further industrial application, we designed a roll to roll fabrication model as displayed in Figure S6. The PCE liquid can be sprayed evenly on Li belt by a nozzle, afterwards the OIHL-Li could be obtained which can be further cut with the desired shape and area for battery assembly. In the light of this continuous formation technology, the OIHL-Li can be applied into practical industry in the future.

3. CONCLUSION In summary, we proposed a simple one-step surface restraint chemical reaction to prepare a LiCl containing organic-inorganic hybrid layer on Li metal anode. Through the surface dehalogenation reaction, LiCl nanoparticles distributed uniformly in the hybrid surface layer,

ACS Paragon Plus Environment

10

Page 11 of 22 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Applied Materials & Interfaces

which is the key point to regulate Li uniform deposition. The organic-inorganic hybrid component offered flexibility and mechanical strength so that the Li electrode cannot pierce the layer. The surface protected Li anode can stably cycle over 3000 hours at a current density of 1.0 mA cm-2 without dendrite growth. When paired with LFP cathode, it showed capacity retention of 90% at 1.0 C. More importantly, the surface protected Li metal anode is easy to scale up, which can be explored as an industry adaptable technique and expanded to other metal anode based batteries.

4. EXPERIMENTAL SECTION 4.1 Preparation of organic-inorganic composite electrode The PCE liquid were dropped directly on lithium metal surface and mopped by the blade. The coating thickness of the OIHL was controlled by the distance between the blade and lithium electrode. After coating, the composite lithium electrode naturally dried in Ar-filled gloves box with moisture and oxygen concentrations less than 0.1 ppm at room temperature. For pouch cells assembling, the pristine lithium belt was coated by PCE liquid, then cuted into the shape and size we need. The thickness of Li foil (in coin cells) and Li belt (in pouch cells) were 200 μm and 50 μm, respectively. 4.2 Characterization SEM (Zeiss SUPRA 55, accelerating voltage at 10 kV) were used to characterize Li anodes’ structure and morphology. XPS measurement were carried out on a Thermo Electron ESCALAB 250 system. The Fourier Transform Infrared (FTIR) spectra were acquired by Nicolet 6700 (Thermo). 4.3 Preparation of LFP cathode

ACS Paragon Plus Environment

11

ACS Applied Materials & Interfaces 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 12 of 22

The LiFePO4 electrode was prepared by spreading a slurry of mixing the commercial LiFePO4 powders, polyvinylidene fluoride (PVDF) binder and conductive carbon black (8:1:1 in weight ratio) on a piece of Al foil. After that, the electrode was dried under vacuum at 120 °C for 12 h. The typical mass loading of the active materials was 3.2 mg cm-2. 4.4 Cells assembling To investigate the electrochemical performance of OHIL-Li electrode and Bare Li electrode, 2032-type coin cells were assembled with Li metal electrode and LFP cathode with ether-based electrolyte (1M LiTFSI in 1:1 DME/DOL with 2 wt.% LiNO3). The amount of electrolyte in Li | Li symmetry cells was 100 μl and in both Li | Cu cells and Li | LFP coin cells was 80 μl. Postdemn SEM characterization and CV test use the Li | Cu cells, which consisted of Li foil and Cu foil current collector. All of modifications went on the metallic Li surface. The practical application of the Bare Li anode can be demonstrated by test the LFP pouch cells. For pouch cell assembling, the Li foil was pressed onto the stain steel mesh and pressed to ensure close contact. The pouch cell consisted of a piece of LFP cathode and a piece of Li foil anode. All the assembly process performed in an Ar-filled gloves box. 4.5 Electrochemical measurement The galvanostatic discharge/charge test was carried out on the LAND battery system at room temperature. For symmetric Li | Li cell tests, the discharge cut-off capacity was 1.0 mAh cm-2 while the current densities were both 1.0 mA cm-2 and 2.0 mA cm-2. In Li | LFP cells, the voltage range was 2.0 V-4.2 V. The cyclic voltammogram curve was tested in the voltage range of 0.5V-3.0 V (vs. Li+/Li) using CHI 660E electrochemical station in Li|Cu half cell system. The electrochemical impedance spectroscopy was also measured by CHI 660E electrochemical station in the frequency range from 100 kHz to 0.01 Hz and using Li|Li symmetric cell.

ACS Paragon Plus Environment

12

Page 13 of 22 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Applied Materials & Interfaces

ASSOCIATED CONTENT Supporting Information The Supporting Information is available free of charge on the (ACS Publications website at DOI: 10.1021/acsami. ) Chemical reaction step of OIHL; FTIR spectra of OIHL; Top-view SEM image of cycled OIHL-Li; The voltage profiles of Li | LFP cells in different rate; The cycled performance of Li | LFP cells at 5.0C; and the industrial preparation design of OIHL-Li (PDF) AUTHOR INFORMATION Corresponding Authors *E-mail: [email protected] *E-mail: [email protected] *E-mail: [email protected] Notes The authors declare no competing financial interest. ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China (21771018, 21875004), Beijing University of Chemical Technology (start-up grant buctrc201901, BUCT, China), the Program for Changjiang Scholars and Innovative Research Team in the University, the Fundamental Research Funds for the Central Universities, and the Long Term Subsidy Mechanism from the Ministry of Finance and the Ministry of Education of PRC.

REREFENCE (1) Shen, Y.; Zhang, Y.; Han, S.; Wang, J.; Peng, Z.; Chen, L. Unlocking the Energy Capabilities of Lithium Metal Electrode with Solid-State Electrolytes. Joule. 2018, 2(9), 1674-1689 (2) Zhang, X.-Q.; Zhao, C.-Z.; Huang, J.-Q.; Zhang, Q. Recent Advances in Energy Chemical Engineering of Next-Generation Lithium Batteries. Engineering. 2018, 4 (6), 831-847.

ACS Paragon Plus Environment

13

ACS Applied Materials & Interfaces 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 14 of 22

(3) Guo, Y.; Li, H.; Zhai, T. Reviving Lithium-Metal Anodes for Next-Generation High-Energy Batteries. Adv. Mater. 2017, 29 (29), e1700007 (4) Liu, Y.; Zhou, G.; Liu, K.; Cui, Y. Design of Complex Nanomaterials for Energy Storage: Past Success and Future Opportunity. Acc. Chem. Res. 2017, 50 (12), 2895-2905 (5) Cheng, X. B.; Zhang, R.; Zhao, C. Z.; Zhang, Q. Toward Safe Lithium Metal Anode in Rechargeable Batteries: A Review. Chem. Rev. 2017, 117 (15), 10403-10473. (6) Gu, Y.; Wang, W. W.; Li, Y. J.; Wu, Q. H.; Tang, S.; Yan, J. W.; Zheng, M. S.; Wu, D. Y.; Fan, C. H.; Hu, W. Q.; Chen, Z. B.; Fang, Y.; Zhang, Q. H.; Dong, Q. F.; Mao, B. W. Designable ultra-smooth ultra-thin solid-electrolyte interphases of three alkali metal anodes. Nat. Commun. 2018, 9 (1), 1339 (7) Li, G.; Gao, Y.; He, X.; Huang, Q.; Chen, S.; Kim, S. H.; Wang, D. Organosulfideplasticized solid-electrolyte interphase layer enables stable lithium metal anodes for long-cycle lithium-sulfur batteries. Nat. Commun. 2017, 8 (1), 850 (8) Cheng, X.-B.; Hou, T.-Z.; Zhang, R.; Peng, H.-J.; Zhao, C.-Z.; Huang, J.-Q.; Zhang, Q. Dendrite-Free Lithium Deposition Induced by Uniformly Distributed Lithium Ions for Efficient Lithium Metal Batteries. Adv. Mater. 2016, 28 (15), 2888-2895 (9) 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 (10) Shen, X.; Liu, H.; Cheng, X.-B.; Yan, C.; Huang, J.-Q. Beyond lithium ion batteries: Higher energy density battery systems based on lithium metal anodes. Energy Stor. Mater. 2018, 12, 161-175 (11) 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 anion-immobilized composite electrolyte for dendrite-free lithium metal anodes. Proc. Natl. Acad. Sci. USA 2017,114(42),11069-11074 (12) Zhang, X.; Liu, T.; Zhang, S.; Huang, X.; Xu, B.; Lin, Y.; Xu, B.; Li, L.; Nan, C.-W.; Shen, Y. Synergistic Coupling between Li6.75La3Zr1.75Ta0.25O12 and Poly(vinylidene fluoride) Induces High Ionic Conductivity, Mechanical Strength, and Thermal Stability of Solid Composite Electrolytes. J. Am. Chem. Soc. 2017, 139(39), 13779-13785 (13) Eshetu, G. G.; Judez, X.; Li, C.; Bondarchuk, O.; Rodriguez-Martinez, L. M.; Zhang, H.; Armand, M. Lithium Azide as an Electrolyte Additive for All-Solid-State Lithium-Sulfur Batteries. Angew. Chem. Int. Ed. Engl. 2017, 56(48), 15368-15372 (14) Wang, C.; Yang, Y.; Liu, X.; Zhong, H.; Xu, H.; Xu, Z.; Shao, H.; Ding, F. Suppression of Lithium Dendrite Formation by Using LAGP-PEO (LiTFSI) Composite Solid Electrolyte and Lithium Metal Anode Modified by PEO (LiTFSI) in All-Solid-State Lithium Batteries. ACS Appl. Mater. Interfaces. 2017, 9 (15), 13694-13702 (15) Yan, K.; Lu, Z.; Lee, H.-W.; Xiong, F.; Hsu, P.-C.; Li, Y.; Zhao, J.; Chu, S.; Cui, Y. Selective deposition and stable encapsulation of lithium through heterogeneous seeded growth. Nat. Energy. 2016, 1 (3), 16010 (16) Liu, W.; Lin, D. C.; Pei, A.; Cui, Y. Stabilizing Lithium Metal Anodes by Uniform Li-Ion Flux Distribution in Nanochannel Confinement. J. Am. Chem. Soc. 2016, 138 (47), 15443-15450 (17) Zhang, R.; Chen, X. R.; Chen, X.; Cheng, X. B.; Zhang, X. Q.; Yan, C.; Zhang, Q. Lithiophilic Sites in Doped Graphene Guide Uniform Lithium Nucleation for Dendrite-Free Lithium Metal Anodes. Angew. Chem. Int. Ed. Engl. 2017, 56 (27), 7764-7768 (18) 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. Engl. 2017, 56(45), 14207-14211 (19) Ding, F.; Xu, W.; Graff, G. L.; Zhang, J.; Sushko, M. L.; Chen, X.; Shao, Y.; Engelhard, M.

ACS Paragon Plus Environment

14

Page 15 of 22 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Applied Materials & Interfaces

H.; Nie, Z.; Xiao, J.; Liu, X.; Sushko, P. V.; Liu, J.; Zhang, J.-G. Dendrite-Free Lithium Deposition via Self-Healing Electrostatic Shield Mechanism. J. Am. Chem. Soc. 2013, 135 (11), 4450-4456 (20) Liu, W.; Mi, Y. Y.; Weng, Z.; Zhong, Y. R.; Wu, Z. S.; Wang, H. L. Functional metalorganic framework boosting lithium metal anode performance via chemical interactions. Chem. Sci. 2017, 8 (6), 4285-4291 (21) Qian, J.; Xu, W.; Bhattacharya, P.; Engelhard, M.; Henderson, W. A.; Zhang, Y.; Zhang, J.G. Dendrite-free Li deposition using trace-amounts of water as an electrolyte additive. Nano. Energy. 2015, 15, 135-144 (22) Kang, H.-K.; Woo, S.-G.; Kim, J.-H.; Yu, J.-S.; Lee, S.-R.; Kim, Y.-J. Few-Layer Graphene Island Seeding for Dendrite-Free Li Metal Electrodes. ACS Appl. Mater. Interfaces. 2016, 8 (40), 26895-26901 (23) Liu, K.; Pei, A.; Lee, H. R.; Kong, B.; Liu, N.; Lin, D. C.; Liu, Y. Y.; Liu, C.; Hsu, P. C.; Bao, Z. A.; Cui, Y. Lithium Metal Anodes with an Adaptive "Solid-Liquid" Interfacial Protective Layer. J. Am. Chem. Soc.2017, 139 (13), 4815-4820 (24) Lin, D. C.; Liu, Y. Y.; Chen, W.; Zhou, G. M.; Liu, K.; Dunn, B.; Cui, Y. Conformal Lithium Fluoride Protection Layer on Three-Dimensional Lithium by Nonhazardous Gaseous Reagent Freon. Nano. Lett. 2017, 17 (6), 3731-3737 (25) Zhao, J.; Liao, L.; Shi, F.; Lei, T.; Chen, G.; Pei, A.; Sun, J.; Yan, K.; Zhou, G.; Xie, J.; Liu, C.; Li, Y.; Liang, Z.; Bao, Z.; Cui, Y. Surface Fluorination of Reactive Battery Anode Materials for Enhanced Stability. J. Am. Chem. Soc. 2017, 139 (33), 11550-11558 (26) Liu, Y. Y.; Lin, D. C.; Yuen, P. Y.; Liu, K.; Xie, J.; Dauskardt, R. H.; Cui, Y. An Artificial Solid Electrolyte Interphase with High Li-Ion Conductivity, Mechanical Strength, and Flexibility for Stable Lithium Metal Anodes. Adv. Mater. 2017, 29 (10), 1605531 (27) Liu, Q.-C.; Xu, J.-J.; Yuan, S.; Chang, Z.-W.; Xu, D.; Yin, Y.-B.; Li, L.; Zhong, H.-X.; Jiang, Y.-S.; Yan, J.-M.; Zhang, X.-B. Artificial Protection Film on Lithium Metal Anode toward Long-Cycle-Life Lithium-Oxygen Batteries. Adv. Mater. 2015, 27 (35), 5241-5247 (28) Bai, M.; Xie, K.; Yuan, K.; Zhang, K.; Li, N.; Shen, C.; Lai, Y.; Vajtai, R.; Ajayan, P.; Wei, B. A Scalable Approach to Dendrite-Free Lithium Anodes via Spontaneous Reduction of SprayCoated Graphene Oxide Layers. Adv. Mater. 2018, 30(29), 1801213 (29) Liu, K.; Liu, W.; Qiu, Y.; Kong, B.; Sun, Y.; Chen, Z.; Zhuo, D.; Lin, D.; Cui, Y. Electrospun core-shell microfiber separator with thermal-triggered flame-retardant properties for lithium-ion batteries. Sci. Adv. 2017, 3(1), e1601978 (30) Manthiram, A.; Yu, X.; Wang, S. Lithium battery chemistries enabled by solid-state electrolytes. Nat. Rev. Mater. 2017, 2, 16103 (31) Yu, X.; Manthiram, A. Electrode–electrolyte interfaces in lithium-based batteries. Energy Environ. Sci. 2018, 11 (3), 527-543 (32) Wang, Q.; Yang, C.; Yang, J.; Wu, K.; Qi, L.; Tang, H.; Zhang, Z.; Liu, W.; Zhou, H. Stable Li metal anode with protected interface for high-performance Li metal batteries. Energy Environ. Sci. 2018, 15, 249-256 (33) Zhang, R.; Chen, X.; Shen, X.; Zhang, X.-Q.; Chen, X.-R.; Cheng, X.-B.; Yan, C.; Zhao, C.-Z.; Zhang, Q. Coralloid Carbon Fiber-Based Composite Lithium Anode for Robust Lithium Metal Batteries. Joule. 2018, 2(4), 764–777 (34) Zhang, X.-Q.; Cheng, X.-B.; Chen, X.; Yan, C.; Zhang, Q. Fluoroethylene Carbonate Additives to Render Uniform Li Deposits in Lithium Metal Batteries. Adv. Funct. Mater. 2017, 27 (10), 1605989

ACS Paragon Plus Environment

15

ACS Applied Materials & Interfaces 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 16 of 22

(35) Gao, Y.; Zhao, Y.; Li, Y. C.; Huang, Q.; Mallouk, T. E.; Wang, D. Interfacial Chemistry Regulation via a Skin-Grafting Strategy Enables High-Performance Lithium-Metal Batteries. J. Am. Chem. Soc. 2017, 139(43), 15288-15291 (36) Liu, F.; Xiao, Q.; Wu, H. B.; Shen, L.; Xu, D.; Cai, M.; Lu, Y. Fabrication of Hybrid Silicate Coatings by a Simple Vapor Deposition Method for Lithium Metal Anodes. Adv. Energy Mater. 2017, 1701744 (37) Zhao, Q.; Tu, Z.; Wei, S.; Zhang, K.; Choudhury, S.; Liu, X.; Archer, L. A. Building Organic/Inorganic Hybrid Interphases for Fast Interfacial Transport in Rechargeable Metal Batteries. Angew. Chem. Int. Ed. Engl. 2017,57(4), 992-996 (38) Pang, Q.; Liang, X.; Kochetkov, I. R.; Hartmann, P.; Nazar, L. F. Stabilizing Lithium Plating by a Biphasic Surface Layer Formed In Situ. Angew. Chem. Int. Ed. Engl. 2018, 57 (31), 9795-9798, (39) Yan, C.; Cheng, X. B.; Yao, Y. X.; Shen, X.; Li, B. Q.; Li, W. J.; Zhang, R.; Huang, J. Q.; Li, H.; Zhang, Q. An Armored Mixed Conductor Interphase on a Dendrite-Free Lithium-Metal Anode. Adv. Mater. 2018, e1804461 (40) Xu, R.; Zhang, X.-Q.; Cheng, X.-B.; Peng, H.-J.; Zhao, C.-Z.; Yan, C.; Huang, J.-Q. Artificial Soft-Rigid Protective Layer for Dendrite-Free Lithium Metal Anode. Adv. Funct. Mater. 2018, 1705838 (41) Zhang, X.-Q.; Cheng, X.-B.; Zhang, Q. Advances in Interfaces between Li Metal Anode and Electrolyte. Adv. Mater. Interfaces. 2018, 5 (2), 1701097 (42) Tao, T.; Lu, S.; Fan, Y.; Lei, W.; Huang, S.; Chen, Y. Anode Improvement in Rechargeable Lithium-Sulfur Batteries. Adv. Mater. 2017, 29 (48)

ACS Paragon Plus Environment

16

Page 17 of 22 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Applied Materials & Interfaces

FIGURES CAPTIONS

Figure 1. A schematic image of the morphology changes of Li metal anode during cycling. a) Typical SEI and Li dendrite formation process. Uneven SEI will form during Li+ deposition, which causes uneven Li+ ions flux and serves dendrite growth. b) Fabrication of OIHL and uniform Li plating on Li metal anode. A uniform LiCl-containing organic-inorganic hybrid layer is fabricated by a simple in-situ method suppress Li dendrite effectively.

ACS Paragon Plus Environment

17

ACS Applied Materials & Interfaces 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 18 of 22

Figure 2. a) C 1s and b) Cl 2p XPS spectra of OIHL-Li anode. The surface of c) pristine Li foil and d) OIHL-Li foil. The cross-section view of e) pristine Li foil and f) OIHL-Li foil.

ACS Paragon Plus Environment

18

Page 19 of 22 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Applied Materials & Interfaces

Figure 3. a) The cyclic voltammogram curve of Li|Cu coin cells. b) The charge and discharge voltage profiles of Li|Cu cells at 1.0 mA cm-2. c) The voltage hysteresis of Li|Cu cells at 0.5 mA cm-2. d) The electrochemical impedance spectroscopy of Li anode and OIHL-Li anode during cycling. The long-time cycling performance of symmetric cells at different current density: e)1.0 mA cm-2 f) 2.0 mA cm-2.

ACS Paragon Plus Environment

19

ACS Applied Materials & Interfaces 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 20 of 22

Figure 4. Surface morphology of Li anode in Li|Cu cells after 50 cycles at 1.0mA cm-2. a) The top view and c) the cross-section view of pristine Li anode. b) The top view and d) cross-section view of OIHL-Li. e) The schematic image of ionic conductivity of the OIHL. f) C 1s XPS spectra of two kinds of Li anode after 15 cycles. g) Cl 2p XPS spectra of two kinds of Li anode after 15 cycles.

ACS Paragon Plus Environment

20

Page 21 of 22 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Applied Materials & Interfaces

Figure 5. The cycling performance of Li | LFP coin cells at a) 1.0 C using ether-based electrolyte and b) 2.0 C using carbonate electrolyte. When using ether-based electrolyte, the capacity rentention of Bare Li| LFP cells was 71.2% after 300 cycles, but the OIHL-Li | LFP cells hold the 89.8% capacity after 350 cycles. And in carbonate system, the OIHL-Li | LFP cells exhibited a high capacity retention of 98% after 200 cycles. c) The frication process of OIHL-Li belt. d) A string of lights contains 80 LEDs lit by the OIHL-Li | LFP pouch cell. e) The chemical performance of Li | LFP pouch cells at 1.0 C using carbonate electrolyte.

ACS Paragon Plus Environment

21

ACS Applied Materials & Interfaces 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 22 of 22

Table of contents

ACS Paragon Plus Environment

22