Carboxylate Anchored Polyvinyl Alcohol Separator

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Lithium Sulfonate/Carboxylate Anchored Polyvinyl Alcohol Separator for Lithium Sulfur Batteries Kai Jiang, Shu Gao, Ruxing Wang, Mao Jiang, Jing Han, Tiantian Gu, Mengyun Liu, Shijie Cheng, and Kangli Wang ACS Appl. Mater. Interfaces, Just Accepted Manuscript • DOI: 10.1021/acsami.8b03290 • Publication Date (Web): 23 Apr 2018 Downloaded from http://pubs.acs.org on April 23, 2018

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ACS Applied Materials & Interfaces

Lithium Sulfonate/Carboxylate Anchored Polyvinyl Alcohol Separator for Lithium Sulfur Batteries Kai Jiangab†, Shu Gaob†, Ruxing Wangb, Mao Jiangb, Jing Hanb, Tiantian Gub, Mengyun Liub, Shijie Chenga and Kangli Wanga* a

State Key Laboratory of Advanced Electromagnetic Engineering and Technology,

School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China b

State Key Laboratory of Materials Processing and Die & Mould Technology, School

of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China *Corresponding Author, Prof. Kangli Wang, E-mail: [email protected], Tel.: +86-27-87559524. Keywords: Polysulfides, Shuttle effects, Anode protection, Polymeric materials, Membranes ABSTRACT The monolayer poly(vinyl alcohol) (PVA)-based separator with pendant sulfonate/carboxylate groups and compact morphology is synthesized to suppress the essential lithium polysulfide permeation in lithium sulfur batteries (LSBs). The Li+ transference number is significantly increased to 0.8 much higher than commercial separator (0.43). The polysulfide retention is verified by idle test in polysulfide-rich electrolyte under internal electric field of cell. The LSB with additive-free electrolyte attains a coulombic efficiency around 98%, a delivered capacity 804 mAh g−1 at 2.5 A 1

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g−1. After 500 cycles, it retains 901 mAh g−1 at 1.5 A g−1 with extra low fading rate 0.016% per cycle. Overall, this monolayer PVA-based separator provides a facile and effective technique to assemble highly stable LSBs. 1. Introduction In comparison to the various energy storage systems including lithium or sodium ion and lead-acid batteries, etc.,1-5 lithium sulfur batteries have drew attention for benefits including low cost, and superior energy density 2600 Wh kg−1.6 Ordinarily, the sulfur cathode follows a two-step redox route including transfer from elemental sulfur to lithium polysulfides then to Li2S solids. However, the ether-based electrolyte could dissolve the polysulfide intermediates while the conventional porous polyolefin-based separator fails to suppress them diffusion to the lithium plate, this leads to the severe shuttle effect and anode depletion.7-8 Numerous efforts have been paid on the intricate host of carbon and metal oxides/hydroxides for high sulfur loading and polysulfide absorption.9 By covalently bonding the reduced graphene oxide-carbon nanotube (rGO-CNT) with nitrogen-rich polymer for polysulfide adsorption, Wen et al. reported the sulfur areal loading up to 18 mg cm–2 with excellent cycle stability.10 Then, the modifications of commercial separator emerged to suppress polysulfide diffusion including coating of conductive carbon framework,8, 11

metal oxides,12-13 black phosphorous14 as the upper current collector and adsorptive

interlayer simultaneously. Manthiram et al. proposed the boron heteroatom-doped CNT as coating layer on the commercial separator to realize the high utilization ratio of sulfur without conductive additive in cathode and polysulfide trapping 2


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simultaneously, this results in a capacity fading rate reduced to 0.04%.15 By grafting styrene sulfonate onto the surface of polypropylene separator, Trabesinger et al. reported an asymmetric separator retarding the polysulfide diffusion without sacrificing the Li+ mobility.16 Qiang et al. reported an coating layer consisted of the porous graphene with the amphiphilic polyvinyl pyrrolidone which is facile to scale up to sulfur loading 7.8 mg cm–2.17 Lately, utilizations of Nafion either coating on commercial separator18 or solely as separator1 were reported to address the polysulfides shuttle benefiting from the sulfonic acid group.19 Ma et al. reported the synthesis of poly(ethylene glycol) dimethacrylate (PEGDMA) based sulfonated UV-crosslinked separator with high lithium transference number.15 Lee et al. reported the lithiated perfluorinated sulfonic acid (Li-PFSA) membrane with sulfonate groups swelling in sulfolane/diglyme mixture as single ion-conductor could deliver 720 mAh g−1 after 100 cycles at 0.1 C with retention ratio 79%,20 the capacity fading is effectively inhibited yet still not satisfactory. Nevertheless, the strategy of applying cation selective barrier in LSBs is inspiring and needs further exploration. The water-soluble and nontoxic polyvinyl alcohol (PVA) is widely used in paper-making, textiles and coating with easiness in film-forming. Its reactive hydroxyl could be used to develop cross-linked three-dimensional networks and feasibly grafted with functional groups. By reacting PVA with boric, oxalic acid and Li2CO3, Wu et al. reported a PVA-based polymeric material serving as both the electrolyte and the separator with high electrochemical window (7 V vs. Li+/Li).21 Deng et al. synthesized poly(methyl acrylate-co-acrylonitrile)/PVA via emulsion 3



polymerization in which PVA served as the compliant framework for flexible battery devices.22 Besides the stability in organic electrolyte, it possesses improved thermal stability in relative to the polyolefin-based separator.23 Xiao et al. prepared porous PVA separator in phase separation method with low thermal shrinkage which is meaningful considering the ohm heat of the internal resistance of battery during operating.24 Herein, the novel PVA-based separator (P-S/C-Li) modified with lithium sulfonate/carboxylate is synthesized. Its promoted Li+ transport and lithium strip/plate property are investigated. In addition to the galvanostatic charge/discharge test, the assembled LSBs (electrolyte additive-free) are idled for 24h during discharge to explore the immobilization of polysulfide. The micromorphology of battery components are also explored after cycling. In addition, a highly stable LSB system is established combining S@rGO composite cathode and P-S/C-Li. 2. Experiments 2.1. Synthesis of P-S/C-Li separator. The 99% hydrolyzed PVA (Mw=89,000-98,000) and sulfosuccinic acid (70 wt% in H2O, Aldrich) were dissolved in distilled water at 60 °C to achieve a light brown aqueous solution. The molar ratio of sulfosuccinic acid to –OH groups in PVA was kept at 1:20. The transparent solution was then scraped on glass substrates. After evaporation in convection at 60 °C, the glass substrate was treated at 120 °C for 24h. Then, the membrane was put in aqueous 0.1 M LiOH at room temperature. Finally, the P-S/C-Li separator was achieved by immersing the membrane in DI water to wash the excessive LiOH, rinsed by EtOH and 60 °C dried for 24h. The proposed synthesis 4


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route of P-S/C-Li functional separator is sketched in Figure 1. The network of PVA is cross-linked due to the single- or bridge-esterification between –COOH and –OH at first, the remained –COOH and pendant –SO3H groups are then lithiated by LiOH to achieve the P-S/C-Li membrane with abundant fixed groups of negatively charged – SO3− and –COO−.

Figure 1. The synthesis route of the P-S/C-Li functional separator. 2.2. Characterization The S@C cathode composite was prepared by melt-diffusion of elemental sulfur/conducting carbon (Super P) (80:20, w/w) at 155 °C for 24h. The S@rGO was obtained by ultrasonic dissolving rGO (0.1 g L−1) in hydrochloric acid (3%) with solution of sodium thiosulfate (2 g L−1). The active materials (S@C or S@rGO), binder (styrene-butadiene rubber/carboxymethyl cellulose, 1:1), and conducting agent (Super P), were grinded together (80:10:10) in DI water which was scraped on aluminum foil with carbon coating (EB-012, MTI) with sulfur loading around 1.7 mg cm−2 and 60 °C dried in vacuum. Membrane of P-S/C-Li and commercial separator (Celgard 2400) both with diameter 16 mm were used to assemble the LSBs with additive-free

1

M

lithium

bis(trifluoromethane

sulfonimide)

(LiTFSI)

1,2-dimethoxyethane/1,3-dioxolane (DME/DOL) (1:1, v/v) as electrolyte and anode of lithium plate. The electrolyte/sulfur ratio in battery assembly was kept around 12 µl 5



mg–1. Galvanostatic charge/discharge at 0.5 A g−1 calculated by sulfur and cyclic voltammogram (CV) at 0.1 mV s−1 was measured over range 1.7-2.8 V. Rate performance is tested in the sequential current densities 0.5, 1.0, 1.5, 2.0 and 2.5 A g−1. 3. Results and discussion Results of FTIR are shown in Figure 2. The1720 and 1240 cm−1 adsorption bands are ascribed to the ester group and its C–O stretching mode separately,25 these suggest the esterification-crosslinking. Moreover, the adsorption band at 1620 and 1033 cm−1 are corresponding to the unreacted carboxyl –COOH and the pendant –SO3H group, respectively.26 After the lithiation, the vibration mode of carboxyl shifts to 1578 cm−1 and –SO3H to 1057 cm−1, owing to the formation of –COOLi and –SO3Li, separately.

Figure 2. The FTIR spectra of cross linked PVA and P-S/C-Li. The chemical valence states in compound P-S/C-Li is explored by X-ray photoelectron spectroscopy (XPS), results of which are given in Figure 3. The binding energy 56.2 eV relates to the coordinated Li+ ions in Figure 3a, while 167.3 eV for S2p stands for the terminated –SO3– groups in Figure 3b. The peaks of C1s in Figure 3c between 282 and 290 eV could be deconvoluted into three components including 6


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284.2, 285.4, and 288.9 eV, ascribing to the C–C bond in polyvinyl chain, the C–O and C=O bonds in cross-linking center –COOC– and terminated –COO– groups, respectively.

Figure 3. XPS measurements of P-S/C-Li for Li1s (a), S2p (b), and C1s (c). As shown in Figure 4a, the cross-linked PVA possesses a compact surface morphology. After the lithiation treatment, the appearance of polymer clusters is observed in Figure 4b owing to the replacement of terminated hydrogen by lithium atom that causes the spatial distortion at the end of polymer chain. The cross-section of P-S/C-Li possesses dense morphology (Figure 4c) and the determined thickness is around 22 µm. Moreover, the compactness of membrane after the Li+ exchange could presumably suppress the polysulfide permeation. The light brown free-standing P-S/C-Li with diameter 16 mm for battery test is presented in Figure S1.

Figure 4. The surface morphology of cross-linked PVA (a), P-S/C-Li (b) and its 7



cross-section (c). The Li+ transference number (t+) is measured using symmetrical Li//Li cells biased to DC voltage (∆V) 10 mV and 1 M LiTFSI DME/DOL (1:1, v/v) as electrolyte. As exhibited in Figure S2a-d, the polarization currents are recorded till steady and EIS of cells are measured at initial and steady states. Values of t+ are calculated by

‫ݐ‬ା = ‫ܫ‬ௌ (∆ܸ − ‫ܫ‬଴ ܴ଴ )/[‫ܫ‬଴ (∆ܸ − ‫ܫ‬ௌ ܴௌ )] , here IS, RS and I0, R0 correspond to the measured currents and impedances of passivation layers at steady and initial states, respectively.15 It is noteworthy that t+ of P-S/C-Li (0.80) almost twice the commercial separator (0.43). Conventionally in the ether-based electrolyte, the lithium ion solvation results in pairs of Li+–ether molecules which is much larger than the dissociated anions TFSI–, this impedes the transport of Li+ ion significantly thus a relatively lower t+ value (0.2–0.4).27 On the contrary, the high t+ value for P-S/C-Li is probably attributed to that the fixated sulfonate/carboxylate groups along the polymer backbones could accelerate the de-solvation of Li+–ether shells by providing Li+ coordination sites to promote the Li+ transport eventually. To evaluate the interfacial stability of separator/lithium, the plate/strip procedure of lithium is evaluated in Li//Li cells which undergo charge and discharge processes each for 2 min at current density 1 mA cm−2. It is observed that the voltage ends in Figure S2e using commercial separator suffer from abrupt fluctuation, this indicates the random and drastic change in surface morphology of lithium. To contrast, the much more stable voltage ends in Figure S2f for P-S/C-Li are owing to the distributed sulfonate and carboxylate groups realizing the uniform dissolution/deposition of Li+.15 Prior to battery assembly, cyclic 8


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voltammogram (CV) is performed at scan rate 2 mV s−1 in Li/P-S/C-Li/stainless steel with 1 M LiTFSI DME/DOL (1:1, v/v). No prominent reduction/oxidation current is observed in Figure S2g, this suggests the electrochemical stability of P-S/C-Li across the operating voltage 1.7-2.8 V. Subsequently, the redox mechanism of LSB applying P-S/C-Li is investigated by CV in the initial five cycles (Figure S2h). With high reversibility indicated by these overlapped curves, no parasite redox couple illustrates the electrochemical stability of P-S/C-Li towards charge/discharge intermediates. The physical blocking of polysulfide is verified by filling the right chamber with 0.05 M Li2S8 DME/DOL (1/1, v/v) countered with blank solvents in left of the H-type diffusion cell and sandwiching the examined separator in between. The Li2S8 solution is prepared by mixing Li2S and elemental sulfur at stoichiometric ratio 1:7 at 80 °C. Driven by the concentration gradient, the diffusion of Li2S8 for commercial separator is significant after 6h (Figure S3c). While, the blank solvent remains colorless for P-S/C-Li (Figure S3d), this suggests its suppression of polysulfide permeation due to the physical shielding ability by its compact and dense structure. More importantly, to verify whether the dissolved polysulfide could readily diffuse to the active anode under internal electric field, LSBs comprising S@C cathode and commercial or P-S/C-Li separator are programed operating as follow: galvanostatic charge/discharge at 0.5 A g−1 while being idled for 24h at 2.15 V during discharge at the 10th cycle, performance of which is plotted in Figure 5a. The irreversible drastic capacity drop 269.3 mAh g−1 for commercial separator in Figure 5b suggests the permanent loss of active material by reaction between polysulfides and lithium anode during the pause. 9



On contrary for P-S/C-Li, the voltage profiles show little variation (Figure 5c). Moreover, the electrolyte of 1 M LiTFSI DME/DOL (1:1, v/v) with 0.2 M Li2S8 additive is applied to measure lithium transference number t+ as well. The plots of EIS and recording current curves are given in Figure S4. The obtained t+ values are 0.46 and 0.82 for the commercial and P-S/C-Li separators, respectively. It is noteworthy that the high t+ value of P-S/C-Li is maintained with the existence of polysulfides, this suggests the Li+ ions transfer dominantly in system applying P-S/C-Li and the diffusions of the anionic polysulfides are adversely suppressed by the compact and dense structure of P-S/C-Li.

Figure 5. Performances of batteries idled at 2.15 V for 24h at the 10th cycle (a). Voltage profiles of cycle 9th, 10th and 11th for commercial separator (b) and P-S/C-Li (c). The rate performances over 0.5-2.5 A g−1 (d). The voltage profiles at 0.5 and 2.5 A g−1 using commercial separator (e) and P-S/C-Li (f). As shown in Figure 5d, the reversible capacities of LSBs with P-S/C-Li and S@C cathode delivered at 0.5, 1, 1.5, 2, 2.5 A g−1 are 1140, 949, 881, 839, 804 mAh g−1, 10


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respectively. While, those of commercial separator are merely 979, 807, 733, 659, 629 mAh g−1. The localization of polysulfide at cathode side by P-S/C-Li is manifested by the voltage profiles as current density ranging. Compared to the significant increase in polarization as cycling to the 4th for commercial separator (Figure 5e), that for P-S/C-Li varies little (Figure 5f). Its voltage gap of charging/discharging increase to 0.3 V at 2.5 A g−1, which is much less than the commercial separator (0.74 V). The much less polarization is attributed to both the promoted Li+ transference alleviating the concentration polarization28 and the shielding effect of P-S/C-Li protecting the lithium anode. The galvanostatic discharge/charge tests at 0.5 A g−1 are measured applying S@C cathode for 200 cycles (Figure S5). The low coulombic efficiency 89% for commercial separator is attributed to that the redox intermediate polysulfides could readily shuttle to the lithium anode that causes reverse inner current flow. However, P-S/C-Li provides a high value 98%, this indicates its extraordinary polysulfide retention by the physical shielding effects arising from the dense morphology of P-S/C-Li compared to the porous structure in commercial separator. Components of disassembled batteries after 200 cycles are subjected to SEM observation. As well known, the commercial separator possesses uniaxial aligned pores with length around 100-300 µm (Figure 6a). After cycle, the dissolved sulfides are trapped in these pores (Figure 6b), this results in the loss of sulfur and enlargement in cell resistance. Moreover, the severe corrosion to almost half depth of the pristine lithium anode by the dissolved polysulfide is observed in Figure 6c. In comparison, the surfaces of 11



P-S/C-Li facing to both S@C cathode (Figure 6d) and lithium anode (Figure 6e) maintain its compact morphology. Due to both the shielding effect of P-S/C-Li and the favorable property of lithium plate/strip, the passivation layer in Figure 6f is much thinner (20 µm).

Figure 6. SEM images of battery components. Commercial separator: pristine (a), after cycle (b), lithium plate (c). P-S/C-Li after cycle: faced to S@C (d) and lithium (e), corresponding lithium plate (f). Due to the conversion mechanism of sulfur cathode, Super P is not an ideal carbon host to bear the corresponding volume change between Li2S and elemental sulfur. Therefore, the rGO sheets with flexible layered structure are used as sulfur hosts to minimize the change in cathode structure and explore the stability of polysulfide suppression by P-S/C-Li during the long-term cycle.29 The sulfur content in composite S@rGO is determined as 82 wt% (Figure 7a). Figure 7b reveals the rGO sheets wrapping around elemental sulfur with dimensional size around 1 µm. The cycle stability of such additive-free LSB applying P-S/C-Li with sulfur area loading 1.7 mg cm−2 at 1.5 A g−1 is illustrated in Figure 7c with initial capacity 980 mAh g−1. After 12


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mere 15 cycles, the battery reaches equilibrium with coulombic efficiency higher than 98%. The assembled battery could operate solidly for 500 cycles and still deliver a capacity 901 mAh g−1, its fading rate is 0.016% per cycle. Figure S6 compares literatures reported lately including the metal-organic framework-based separator,30 polyolefin separators coupled with interlayer of black phosphorous14 and coatings of Nafion19,

31-32

. It is noteworthy that such monolayer functional P-S/C-Li separator

with the lowest fading rate and highest capacity outperforms other multi-layer strategies, this suggests its potential in establishing LSB with excellent cycle stability.

Figure 7. The weight loss curve (a) and micro-morphology (b) of S@rGO. The cycle stability of LSB applying P-S/C-Li at 1.5 A g−1 (c). Conclusion In conclusion, the P-S/C-Li separator is facilely synthesized via crosslinking and lithiation to transfer Li+ and immobilize the polysulfide by its dense and compact morphology. In addition to the H-type diffusion cell test, its immobilization of polysulfide is verified under the internal electric field of LSB. The LSB comprising P-S/C-Li and additive-free electrolyte possesses superior properties including capacity retention up to 901 mAh g−1 with decay rate 0.016% each cycle at 1.5 A g−1 after 500 13



cycles, coulombic efficiency around 98% at 0.5 A g−1 and capacity 804 mAh g−1 delivered at 2.5 A g−1. In comparison to the corrosion of anode with commercial separator, the lithium is effectively protected by P-S/C-Li due to the distributed lithium carboxylate/sulfonate groups. Therefore, such functional P-S/C-Li is ideal in establishing ultra-stable high performance LSBs. Acknowledgements For this work, Kai Jiang and Shu Gao contribute equally. Author Kangli Wang received funding from the 973 Program (2015CB258400), Natural Science Foundation of China (Grant No. 51622703). Author Kai Jiang received funding from the Major Project of Technological Innovation in Hubei Province (2016AAA038). For SEM measurements, the authors thank Analytical and Testing Center of HUST. Supporting Information. Photograph of P-S/C-Li separator (Figure S1). Lithium transference numbers in 1 M LiTFSI electrolytes, plating/striping behavior on lithium electrodes, CV measurements in Li//Li symmetrical cell and LSB applying P-S/C-Li (Figure S2). Polysulfide permeation tests (Figure S3). Lithium transference numbers in 1 M LiTFSI + 0.2 M Li2S8 DME/DOL (1:1, v/v) (Figure S4). Galvanostatic charge/discharge performance applying S@C cathodes (Figure S5). Performance comparison among literatures reporting functional separators (Figure S6). REFERENCES (1) Yu, X.; Joseph, J.; Manthiram, A. Polymer Lithium-Sulfur Batteries with a Nafion Membrane and an Advanced Sulfur Electrode. J. Mater. Chem. A 2015, 3 (30), 15683-15691. 14


Page 14 of 27

Page 15 of 27 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


(2) Eftekhari, A.; Jian, Z.; Ji, X. Potassium Secondary Batteries. ACS Appl. Mater. Interfaces 2017, 9 (5), 4404–4419. (3) Li, W.; Zhou, M.; Li, H.; Wang, K.; Cheng, S.; Jiang, K. A High Performance Sulfur-Doped Disordered Carbon Anode for Sodium Ion Batteries. Energy Environ. Sci. 2015, 8 (10), 2916-2921. (4) Zhang, Q.; Wang, W.; Wang, Y.; Feng, P.; Wang, K.; Cheng, S.; Jiang, K. Controllable Construction of 3D-Skeleton-Carbon Coated Na3V2(PO4)3 for High-Performance Sodium Ion Battery Cathode. Nano Energy 2016, 20, 11-19. (5) Li, H.; Wang, K.; Cheng, S.; Jiang, K. High Performance Liquid Metal Battery with Environmentally Friendly Antimony-Tin Positive Electrode. ACS Appl. Mater. Interfaces 2016, 8 (20), 12830-12835. (6) Tao, X.; Wang, J.; Liu, C.; Wang, H.; Yao, H.; Zheng, G.; Seh, Z. W.; Cai, Q.; Li, W.; Zhou, G.; Zu, C.; Cui, Y. Balancing Surface Adsorption and Diffusion of Lithium-Polysulfides on Nonconductive Oxides for Lithium–Sulfur Battery Design. Nat. Commun.

2016, 7, 11203.

(7) Gao, S.; Wang, K.; Wang, R.; Jiang, M.; Han, J.; Gu, T.; Cheng, S.; Jiang, K. Poly(vinylidene Fluoride)-Based Hybrid Gel Polymer Electrolytes for Additive-Free Lithium Sulfur Batteries. J. Mater. Chem. A 2017, 5 (34), 17889-17895. (8) Huang, J.-Q.; Zhuang, T.-Z.; Zhang, Q.; Peng, H.-J.; Chen, C.-M.; Wei, F. Permselective Graphene Oxide Membrane for Highly Stable and Anti-Self-Discharge Lithium–Sulfur Batteries. ACS Nano 2015, 9 (3), 3002-3011. (9) Liu, M.; Qin, X.; He, Y.-B.; Li, B.; Kang, F. Recent Innovative Configurations in 15



High-Energy Lithium-Sulfur Batteries. J. Mater. Chem. A 2017, 5 (11), 5222-5234. (10) Hong, X.; Jin, J.; Wu, T.; Lu, Y.; Zhang, S.; Chen, C.; Wen, Z. A rGO-CNT Aerogel Covalently Bonded with a Nitrogen-Rich Polymer as a Polysulfide Adsorptive Cathode for High Sulfur Loading Lithium Sulfur Batteries. J. Mater. Chem. A 2017, 5 (28), 14775-14782. (11) Chung, S.-H.; Manthiram, A. Bifunctional Separator with a Light-Weight Carbon-Coating for Dynamically and Statically Stable Lithium-Sulfur Batteries. Adv. Funct. Mater. 2014, 24 (33), 5299-5306. (12) Qian, X.; Jin, L.; Zhao, D.; Yang, X.; Wang, S.; Shen, X.; Rao, D.; Yao, S.; Zhou, Y.; Xi, X. Ketjen Black-MnO Composite Coated Separator For High Performance Rechargeable Lithium-Sulfur Battery. Electrochim. Acta 2016, 192, 346-356. (13) Wang, R.; Wang, K.; Gao, S.; Jiang, M.; Zhou, M.; Cheng, S.; Jiang, K. Rational Design of Yolk-Shell Silicon Dioxide@Hollow Carbon Spheres as Advanced Li-S Cathode Hosts. Nanoscale 2017, 9 (39), 14881-14887. (14) Sun, J.; Sun, Y.; Pasta, M.; Zhou, G.; Li, Y.; Liu, W.; Xiong, F.; Cui, Y. Entrapment of Polysulfides by a Black-Phosphorus-Modified Separator for Lithium– Sulfur Batteries. Adv. Mater. 2016, 28 (44), 9797-9803. (15) Chung, S.-H.; Han, P.; Manthiram, A. A Polysulfide-Trapping Interface for Electrochemically Stable Sulfur Cathode Development. ACS Appl. Mater. Interfaces 2016, 8 (7), 4709-4717. (16) Conder, J.; Forner-Cuenca, A.; Gubler, E. M.; Gubler, L.; Novák, P.; Trabesinger, S. Performance-Enhancing Asymmetric Separator for Lithium–Sulfur Batteries. ACS 16


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Appl. Mater. Interfaces 2016, 8 (29), 18822-18831. (17) Zhai, P.-Y.; Peng, H.-J.; Cheng, X.-B.; Zhu, L.; Huang, J.-Q.; Zhu, W.; Zhang, Q. Scaled-Up Fabrication of Porous-Graphene-Modified Separators for High-Capacity Lithium–Sulfur Batteries. Energy Storage Mater. 2017, 7, 56-63. (18) Bauer, I.; Thieme, S.; Brückner, J.; Althues, H.; Kaskel, S. Reduced Polysulfide Shuttle in Lithium–Sulfur Batteries Using Nafion-Based Separators. J. Power Sources 2014, 251, 417-422. (19) Huang, J.-Q.; Zhang, Q.; Peng, H.-J.; Liu, X.-Y.; Qian, W.-Z.; Wei, F. Ionic Shield for Polysulfides Towards Highly-Stable Lithium-Sulfur Batteries. Energy Environ. Sci. 2014, 7 (1), 347-353. (20) Lee, J.; Song, J.; Lee, H.; Noh, H.; Kim, Y.-J.; Kwon, S. H.; Lee, S. G.; Kim, H.-T. A Nanophase-Separated, Quasi-Solid-State Polymeric Single-Ion Conductor: Polysulfide Exclusion for Lithium–Sulfur Batteries. ACS Energy Lett. 2017, 2 (5), 1232–1239. (21) Zhu, Y. S.; Wang, X. J.; Hou, Y. Y.; Gao, X. W.; Liu, L. L.; Wu, Y. P.; Shimizu, M. A New Single-Ion Polymer Electrolyte Based on Polyvinyl Alcohol for Lithium Ion Batteries. Electrochim. Acta 2013, 87 (1), 113-118. (22) Ma, X.; Huang, X.; Gao, J.; Zhang, S.; Deng, Z.; Suo, J.; Ma, X.; Huang, X.; Gao, J.; Zhang, S. Compliant Gel Polymer Electrolyte Based on Poly(Methyl Acrylate-co-Acrylonitrile)/Poly(Vinyl Alcohol) for Flexible Lithium-Ion Batteries. Electrochim. Acta 2014, 115 (115), 216-222. (23) Vaalma, C.; Giffin, G. A.; Buchholz, D.; Passerini, S. Non-Aqueous K-Ion 17



Battery Based on Layered K0.3MnO2 and Hard Carbon/Carbon Black. J. Electrochem. Soc. 2016, 163 (7), A1295-A1299. (24) Xiao, W.; Zhao, L.; Gong, Y.; Liu, J.; Yan, C. Preparation and Performance of Poly(Vinyl Alcohol) Porous Separator for Lithium-Ion Batteries. J. Membr. Sci. 2015, 487 (1), 221-228. (25) Rhim, J.-W.; Park, H. B.; Lee, C.-S.; Jun, J.-H.; Kim, D. S.; Lee, Y. M. Crosslinked Poly(Vinyl Alcohol) Membranes Containing Sulfonic Acid Group: Proton and Methanol Transport Through Membranes. J. Membr. Sci. 2004, 238 (1–2), 143-151. (26) Kim, D. S.; Park, H. B.; Rhim, J. W.; Moo Lee, Y. Preparation and Characterization of Crosslinked PVA/SiO2 Hybrid Membranes Containing Sulfonic Acid Groups for Direct Methanol Fuel Cell Applications. J. Membr. Sci. 2004, 240 (1–2), 37-48. (27) Suo, L.; Hu, Y. S.; Li, H.; Armand, M.; Chen, L. A New Class of Solvent-in-Salt Electrolyte for High-Energy Rechargeable Metallic Lithium Batteries. Nat. Commun. 2013, 4 (2), 1481. (28) Liu, M.; Zhou, D.; He, Y.-B.; Fu, Y.; Qin, X.; Miao, C.; Du, H.; Li, B.; Yang, Q.-H.; Lin, Z.; Zhao, T. S.; Kang, F. Novel Gel Polymer Electrolyte for High-Performance Lithium–Sulfur Batteries. Nano Energy 2016, 22, 278-289. (29) Wang, H.; Yang, Y.; Liang, Y.; Robinson, J. T.; Li, Y.; Jackson, A.; Cui, Y.; Dai, H. Graphene-Wrapped Sulfur Particles as a Rechargeable Lithium–Sulfur Battery Cathode Material with High Capacity and Cycling Stability. Nano Lett. 2011, 11 (7), 18


Page 18 of 27

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2644-2647. (30) Bai, S.; Liu, X.; Zhu, K.; Wu, S.; Zhou, H. Metal–Organic Framework-Based Separator for Lithium–Sulfur Batteries. Nat. Energy 2016, 1, 16094. (31) Zhuang, T.-Z.; Huang, J.-Q.; Peng, H.-J.; He, L.-Y.; Cheng, X.-B.; Chen, C.-M.; Zhang, Q. Rational Integration of Polypropylene/Graphene Oxide/Nafion as Ternary-Layered Separator to Retard the Shuttle of Polysulfides for Lithium–Sulfur Batteries. Small 2016, 12 (3), 381-389. (32) Lu, Y.; Gu, S.; Guo, J.; Rui, K.; Chen, C.; Zhang, S.; Jin, J.; Yang, J.; Wen, Z. Sulfonic Groups Originated Dual-Functional Interlayer for High Performance Lithium–Sulfur Battery. ACS Appl. Mater. Interfaces 2017, 9 (17), 14878-14888.

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Fig. 1. The synthesis route of the P-S/C-Li functional separator. 56x16mm (300 x 300 DPI)


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Fig. 2. The FTIR spectra of cross linked PVA and P-S/C-Li. 58x41mm (300 x 300 DPI)



Fig. 3. XPS measurements of P-S/C-Li for Li1s (a), S2p (b), and C1s (c). 61x21mm (300 x 300 DPI)


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Fig. 4. The surface morphology of cross-linked PVA (a), P-S/C-Li (b) and its cross-section (c). 165x51mm (300 x 300 DPI)



Fig. 5. Performances of batteries idled at 2.15 V for 24h at the 10th cycle (a). The voltage profiles of the 9th, 10th and 11th cycles for commercial separator (b) and P-S/C-Li (c). The rate performances over 0.52.5 A g−1 (d). The voltage profiles at 0.5 and 2.5 A g−1 using commercial separator (e) and P-S/C-Li (f). 155x82mm (300 x 300 DPI)


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Fig. 6. SEM images of battery components. Commercial separator: pristine (a), after cycle (b), lithium plate (c). P-S/C-Li after cycle: facing to S@C (d) and lithium (e), lithium plate (f). 165x110mm (300 x 300 DPI)



Fig. 7. The weight loss curve (a) and micro-morphology (b) of S@rGO. The cycle stability of LSB applying PS/C-Li at 1.5 A g−1 (c). 58x41mm (300 x 300 DPI)


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83x35mm (300 x 300 DPI)


Carboxylate Anchored Polyvinyl Alcohol Separator

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