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Stefano Passerini - One of the best experts on this subject based on the ideXlab platform.
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nitrile functionalized silyl ether with dissolved litfsi as new electrolyte solvent for Lithium ion batteries
2015Co-Authors: Benjamin Pohl, Stefano Passerini, Mariano Grunebaum, Mathias Drews, Martin Winter, Hansdieter WiemhoferAbstract:Abstract 3-((Trimethylsilyl) oxy) propionitrile is introduced as non-volatile solvent for Lithium-ion battery electrolytes using LiTFSI as Lithium Salt. The thermal and chemical stability of the electrolytes offer an enhanced safety as compared to conventional volatile carbonate electrolytes. In cell tests, the investigated LiTFSI nitrile silyl ether electrolyte shows compatibility with LiFePO4, LiNi0.33Mn0.33Co0.33O2 and graphite active materials.
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uv cross linked Lithium conducting ternary polymer electrolytes containing ionic liquids
2010Co-Authors: Guktae Kim, Giovanni Battista Appetecchi, Stefano Passerini, Andrea Balducci, Martin Winter, Maria Carewska, Mario JoostAbstract:Abstract In this manuscript is reported an attempt to prepare high ionic conductivity Lithium polymer electrolytes by UV cross-linking the poly(ethyleneoxide) (briefly called PEO) polymer matrix in presence of the plasticizing Lithium Salt, Lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and an ionic liquid of the pyrrolidinium family (N-alkyl-N-methylpyrrolidinium TFSI) having a common anion with the Lithium Salt. It is demonstrated that polymer electrolytes with room temperature ionic conductivities of nearly 10−3 S cm−1 could be obtained as a result of the reduced crystallinity of the ternary electrolytes. The results clearly indicate that the cross-linked ternary electrolyte shows superior mechanical properties with respect to the non-cross-linked electrolytes and higher conductivities with respect to polymer electrolytes containing none or less ionic liquid.
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Lithium insertion in graphite from ternary ionic liquid Lithium Salt electrolytes ii evaluation of specific capacity and cycling efficiency and stability at room temperature
2009Co-Authors: Simon Franz Lux, Giovanni Battista Appetecchi, Stefano Passerini, Martin Winter, Martin Schmuck, Andrea BalducciAbstract:Abstract In this paper we report the results about the use of ternary room temperature ionic liquid–Lithium Salt mixtures as electrolytes for Lithium-ion battery systems. Mixtures of N -methyl- N -propyl pyrrolidinium bis(fluorosulfonyl) imide, PYR 13 FSI, and N -butyl- N -methylpyrrolidinium bis(trifluoromethansulfonyl) imide, PYR 14 TFSI, with Lithium hexafluorophosphate, LiPF 6 and Lithium bis(trifluoromethansulfonyl) imide, LiTFSI, containing 5 wt.% of vinylene carbonate (VC) as additive, have been used in combination with a commercial graphite, KS6 TIMCAL. The performance of the graphite electrodes has been considered in term of specific capacity, cycling efficiency and cycling stability. The results clearly show the advantage of the use of ternary mixtures on the performance of the graphite electrode.
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Lithium insertion in graphite from ternary ionic liquid-Lithium Salt electrolytesI. Electrochemical characterization of the electrolytes
2009Co-Authors: Giovanni Battista Appetecchi, Maria Montanino, Martin Winterb, Simon Franz Lux, Andrea Balducci, Stefano PasseriniAbstract:In this paper we report the results of chemical-physical investigation performed on ternary room temperature ionic liquid–Lithium Salt mixtures as electrolytes for Lithium-ion battery systems. The ternary electrolytes were made by mixing N-methyl-N-propyl pyrrolidinium bis(fluorosulfonyl) imide (PYR13FSI) and N-butyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl) imide (PYR14TFSI) ionic liquids with Lithium hexafluorophosphate (LiPF6) or Lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). The mixtures were developed based on preliminary results on the cyclability of graphite electrodes in the IL-LiX binary electrolytes. The results clearly show the beneficial synergic effect of the two ionic liquids on the electrochemical properties of the mixtures.
Seiji Tsuzuki - One of the best experts on this subject based on the ideXlab platform.
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physicochemical compatibility of highly concentrated solvate ionic liquids and a low viscosity solvent
2019Co-Authors: Keitaro Takahashi, Seiji Tsuzuki, Masayoshi Watanabe, Yuki Ishino, Wataru Murata, Yasuhiro Umebayashi, Hiromitsu Takaba, Shiro SekiAbstract:High ionic carrier mobilities are important for the electrolyte solutions used in high-performance batteries. Based on the functional sharing concept, we fabricated mixed electrolytes consisting of solvate ionic liquids (SIL), which are highly concentrated solution electrolyte, and the non-coordinating low-viscosity dilution solvent 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether (HFE). We investigated the thermal, transport, and static properties of electrolytes with different ratios of SIL to HFE. In particular, the interactions between the SILs and HFE and static correlations of the coordinating (ether-based molecules), non-coordinating (HFE), and carrier ionic species (Lithium Salt) were clarified by applying the excess density concept. Ether molecules always formed strong complexes with Lithium cations regardless of the absence or presence of HFE. The repulsion force between the SILs and HFE was strongly affected by Lithium Salt concentration. From our results, we proposed dissociation/association models for these electrolyte systems.
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quaternary ammonium room temperature ionic liquid including an oxygen atom in side chain Lithium Salt binary electrolytes ionic conductivity and 1h 7li and 19f nmr studies on diffusion coefficients and local motions
2008Co-Authors: Kikuko Hayamizu, Shiro Seki, Seiji Tsuzuki, Yasutaka Ohno, Hajime Miyashiro, Yo KobayashiAbstract:A room-temperature ionic liquid (RTIL) of a quaternary ammonium cation having an ether chain, N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethylsulfonyl)amide (DEME-TFSA), is a candidate for use as an electrolyte of Lithium secondary batteries. In this study, the electrochemical ionic conductivity, σ, of the neat DEME-TFSA and DEME-TFSA-Li doped with five different concentrations of Lithium Salt (LiTFSA) was measured and correlated with NMR measurements of the diffusion coefficients D and the spin−lattice relaxation times T1 of the individual components DEME (1H), TFSA (19F), and Lithium ion (7Li). The ion conduction of charged ions can be activated with less thermal energy than ion diffusion which contains a contribution from paired ions in DEME-TFSA. In the doped DEME-TFSA-Li samples, the σ and D values decreased with increasing Salt concentration, and within the same sample generally DLi < DTFSA < DDEME except for the sample having the lowest Salt concentration at low temperatures. Sin...
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quaternary ammonium room temperature ionic liquid including an oxygen atom in side chain Lithium Salt binary electrolytes ionic conductivity and 1h 7li and 19f nmr studies on diffusion coefficients and local motions
2008Co-Authors: Kikuko Hayamizu, Shiro Seki, Seiji Tsuzuki, Yasutaka Ohno, Hajime Miyashiro, Yo KobayashiAbstract:A room-temperature ionic liquid (RTIL) of a quaternary ammonium cation having an ether chain, N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethylsulfonyl)amide (DEME-TFSA), is a candidate for use as an electrolyte of Lithium secondary batteries. In this study, the electrochemical ionic conductivity, sigma, of the neat DEME-TFSA and DEME-TFSA-Li doped with five different concentrations of Lithium Salt (LiTFSA) was measured and correlated with NMR measurements of the diffusion coefficients D and the spin-lattice relaxation times T1 of the individual components DEME (1H), TFSA (19F), and Lithium ion (7Li). The ion conduction of charged ions can be activated with less thermal energy than ion diffusion which contains a contribution from paired ions in DEME-TFSA. In the doped DEME-TFSA-Li samples, the sigma and D values decreased with increasing Salt concentration, and within the same sample generally DLi
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imidazolium based room temperature ionic liquid for Lithium secondary batteries effects of Lithium Salt concentration
2007Co-Authors: Shiro Seki, Kikuko Hayamizu, Yasutaka Ohno, Hajime Miyashiro, Yo Kobayashi, Akira Usami, Yuichi Mita, Hiroyuki Tokuda, Masayoshi Watanabe, Seiji TsuzukiAbstract:To understand the basic properties of Lithium secondary batteries which consist of nonflammable and nonvolatile room-temperature ionic liquid electrolytes, we examined the ionic conductivity, electrolyte/electrode interfacial resistance, and charge-discharge rate characteristics by varying the Lithium Salt concentration in the room-temperature ionic liquid, Lithium Salt binary electrolytes. By using a modified imidazolium cation-based room-temperature ionic liquid as an electrolyte, the Lithium secondary batteries achieved a stable charge-discharge operation of more than 100 cycles (cathode LiCoO 2 , anode Lithium metal, voltage region 3.0-4.2 V, current density 1/8 C). Moreover, we found that an optimal Lithium Salt concentration exists for obtaining an excellent battery rate performance, which depends on delicate balances in several factors, such as ionic conductivity (viscosity), interfacial resistances at the LiCoO 2 cathode/electrolyte interface, and the Lithium metal anode/electrolyte interface.
Yo Kobayashi - One of the best experts on this subject based on the ideXlab platform.
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quaternary ammonium room temperature ionic liquid including an oxygen atom in side chain Lithium Salt binary electrolytes ionic conductivity and 1h 7li and 19f nmr studies on diffusion coefficients and local motions
2008Co-Authors: Kikuko Hayamizu, Shiro Seki, Seiji Tsuzuki, Yasutaka Ohno, Hajime Miyashiro, Yo KobayashiAbstract:A room-temperature ionic liquid (RTIL) of a quaternary ammonium cation having an ether chain, N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethylsulfonyl)amide (DEME-TFSA), is a candidate for use as an electrolyte of Lithium secondary batteries. In this study, the electrochemical ionic conductivity, σ, of the neat DEME-TFSA and DEME-TFSA-Li doped with five different concentrations of Lithium Salt (LiTFSA) was measured and correlated with NMR measurements of the diffusion coefficients D and the spin−lattice relaxation times T1 of the individual components DEME (1H), TFSA (19F), and Lithium ion (7Li). The ion conduction of charged ions can be activated with less thermal energy than ion diffusion which contains a contribution from paired ions in DEME-TFSA. In the doped DEME-TFSA-Li samples, the σ and D values decreased with increasing Salt concentration, and within the same sample generally DLi < DTFSA < DDEME except for the sample having the lowest Salt concentration at low temperatures. Sin...
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quaternary ammonium room temperature ionic liquid including an oxygen atom in side chain Lithium Salt binary electrolytes ionic conductivity and 1h 7li and 19f nmr studies on diffusion coefficients and local motions
2008Co-Authors: Kikuko Hayamizu, Shiro Seki, Seiji Tsuzuki, Yasutaka Ohno, Hajime Miyashiro, Yo KobayashiAbstract:A room-temperature ionic liquid (RTIL) of a quaternary ammonium cation having an ether chain, N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethylsulfonyl)amide (DEME-TFSA), is a candidate for use as an electrolyte of Lithium secondary batteries. In this study, the electrochemical ionic conductivity, sigma, of the neat DEME-TFSA and DEME-TFSA-Li doped with five different concentrations of Lithium Salt (LiTFSA) was measured and correlated with NMR measurements of the diffusion coefficients D and the spin-lattice relaxation times T1 of the individual components DEME (1H), TFSA (19F), and Lithium ion (7Li). The ion conduction of charged ions can be activated with less thermal energy than ion diffusion which contains a contribution from paired ions in DEME-TFSA. In the doped DEME-TFSA-Li samples, the sigma and D values decreased with increasing Salt concentration, and within the same sample generally DLi
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imidazolium based room temperature ionic liquid for Lithium secondary batteries effects of Lithium Salt concentration
2007Co-Authors: Shiro Seki, Kikuko Hayamizu, Yasutaka Ohno, Hajime Miyashiro, Yo Kobayashi, Akira Usami, Yuichi Mita, Hiroyuki Tokuda, Masayoshi Watanabe, Seiji TsuzukiAbstract:To understand the basic properties of Lithium secondary batteries which consist of nonflammable and nonvolatile room-temperature ionic liquid electrolytes, we examined the ionic conductivity, electrolyte/electrode interfacial resistance, and charge-discharge rate characteristics by varying the Lithium Salt concentration in the room-temperature ionic liquid, Lithium Salt binary electrolytes. By using a modified imidazolium cation-based room-temperature ionic liquid as an electrolyte, the Lithium secondary batteries achieved a stable charge-discharge operation of more than 100 cycles (cathode LiCoO 2 , anode Lithium metal, voltage region 3.0-4.2 V, current density 1/8 C). Moreover, we found that an optimal Lithium Salt concentration exists for obtaining an excellent battery rate performance, which depends on delicate balances in several factors, such as ionic conductivity (viscosity), interfacial resistances at the LiCoO 2 cathode/electrolyte interface, and the Lithium metal anode/electrolyte interface.
Kikuko Hayamizu - One of the best experts on this subject based on the ideXlab platform.
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a divalent Lithium Salt li2b12f12 dissolved in propylene carbonate studied by nmr methods
2009Co-Authors: Kikuko Hayamizu, Akira Matsuo, Juichi AraiAbstract:A divalent Lithium Salt Li 2 B 12 F 12 dissolved in propylene carbonate (PC) with four different concentrations was studied by NMR methods and ionic conductivity. The individual diffusion coefficients were measured by 1 H, 7 Li, and 19 F pulsed-gradient spin-echo NMR for the solvent PC (D PC ), Lithium (D Li ), and anion (D anion ). Because two-step Salt dissociation processes can be assumed for the divalent Li 2 B 12 F 12 , the existence of LiB 12 F - 12 in addition to Li + and B 12 F 2- 12 must be taken into account. The comparison was made with the diffusion coefficients of LiPF 6 in PC. The plots of ion diffusion coefficients vs solvent diffusion coefficient were linear for both Li 2 B 12 F 12 and LiPF 6 PC in solutions. Although the PF 6 diffusion is much faster than Lithium diffusion for the LiPF 6 in PC, the D Li and Danion of the Li 2 B 12 F 12 have similar values in the temperature range measured for the four different Salt concentrations. The experimental parameters R Li = D Li /D PC and R anion = D anion/ D PC calculated from the individual diffusion coefficients suggest that the PC solvation around B 12 F 12 can be assumed in addition to the PC solvation around Li. Tentatively, the Nernst-Einstein ionic conductivities σ NE were calculated from the D Li and D anion under the assumption of the complete ion dissociation. The temperature- and concentration-dependent behaviors resemble those of the ionic conductivity σ ac observed by the electrochemical ac method.
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quaternary ammonium room temperature ionic liquid including an oxygen atom in side chain Lithium Salt binary electrolytes ionic conductivity and 1h 7li and 19f nmr studies on diffusion coefficients and local motions
2008Co-Authors: Kikuko Hayamizu, Shiro Seki, Seiji Tsuzuki, Yasutaka Ohno, Hajime Miyashiro, Yo KobayashiAbstract:A room-temperature ionic liquid (RTIL) of a quaternary ammonium cation having an ether chain, N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethylsulfonyl)amide (DEME-TFSA), is a candidate for use as an electrolyte of Lithium secondary batteries. In this study, the electrochemical ionic conductivity, σ, of the neat DEME-TFSA and DEME-TFSA-Li doped with five different concentrations of Lithium Salt (LiTFSA) was measured and correlated with NMR measurements of the diffusion coefficients D and the spin−lattice relaxation times T1 of the individual components DEME (1H), TFSA (19F), and Lithium ion (7Li). The ion conduction of charged ions can be activated with less thermal energy than ion diffusion which contains a contribution from paired ions in DEME-TFSA. In the doped DEME-TFSA-Li samples, the σ and D values decreased with increasing Salt concentration, and within the same sample generally DLi < DTFSA < DDEME except for the sample having the lowest Salt concentration at low temperatures. Sin...
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quaternary ammonium room temperature ionic liquid including an oxygen atom in side chain Lithium Salt binary electrolytes ionic conductivity and 1h 7li and 19f nmr studies on diffusion coefficients and local motions
2008Co-Authors: Kikuko Hayamizu, Shiro Seki, Seiji Tsuzuki, Yasutaka Ohno, Hajime Miyashiro, Yo KobayashiAbstract:A room-temperature ionic liquid (RTIL) of a quaternary ammonium cation having an ether chain, N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethylsulfonyl)amide (DEME-TFSA), is a candidate for use as an electrolyte of Lithium secondary batteries. In this study, the electrochemical ionic conductivity, sigma, of the neat DEME-TFSA and DEME-TFSA-Li doped with five different concentrations of Lithium Salt (LiTFSA) was measured and correlated with NMR measurements of the diffusion coefficients D and the spin-lattice relaxation times T1 of the individual components DEME (1H), TFSA (19F), and Lithium ion (7Li). The ion conduction of charged ions can be activated with less thermal energy than ion diffusion which contains a contribution from paired ions in DEME-TFSA. In the doped DEME-TFSA-Li samples, the sigma and D values decreased with increasing Salt concentration, and within the same sample generally DLi
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imidazolium based room temperature ionic liquid for Lithium secondary batteries effects of Lithium Salt concentration
2007Co-Authors: Shiro Seki, Kikuko Hayamizu, Yasutaka Ohno, Hajime Miyashiro, Yo Kobayashi, Akira Usami, Yuichi Mita, Hiroyuki Tokuda, Masayoshi Watanabe, Seiji TsuzukiAbstract:To understand the basic properties of Lithium secondary batteries which consist of nonflammable and nonvolatile room-temperature ionic liquid electrolytes, we examined the ionic conductivity, electrolyte/electrode interfacial resistance, and charge-discharge rate characteristics by varying the Lithium Salt concentration in the room-temperature ionic liquid, Lithium Salt binary electrolytes. By using a modified imidazolium cation-based room-temperature ionic liquid as an electrolyte, the Lithium secondary batteries achieved a stable charge-discharge operation of more than 100 cycles (cathode LiCoO 2 , anode Lithium metal, voltage region 3.0-4.2 V, current density 1/8 C). Moreover, we found that an optimal Lithium Salt concentration exists for obtaining an excellent battery rate performance, which depends on delicate balances in several factors, such as ionic conductivity (viscosity), interfacial resistances at the LiCoO 2 cathode/electrolyte interface, and the Lithium metal anode/electrolyte interface.
Shiro Seki - One of the best experts on this subject based on the ideXlab platform.
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physicochemical compatibility of highly concentrated solvate ionic liquids and a low viscosity solvent
2019Co-Authors: Keitaro Takahashi, Seiji Tsuzuki, Masayoshi Watanabe, Yuki Ishino, Wataru Murata, Yasuhiro Umebayashi, Hiromitsu Takaba, Shiro SekiAbstract:High ionic carrier mobilities are important for the electrolyte solutions used in high-performance batteries. Based on the functional sharing concept, we fabricated mixed electrolytes consisting of solvate ionic liquids (SIL), which are highly concentrated solution electrolyte, and the non-coordinating low-viscosity dilution solvent 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether (HFE). We investigated the thermal, transport, and static properties of electrolytes with different ratios of SIL to HFE. In particular, the interactions between the SILs and HFE and static correlations of the coordinating (ether-based molecules), non-coordinating (HFE), and carrier ionic species (Lithium Salt) were clarified by applying the excess density concept. Ether molecules always formed strong complexes with Lithium cations regardless of the absence or presence of HFE. The repulsion force between the SILs and HFE was strongly affected by Lithium Salt concentration. From our results, we proposed dissociation/association models for these electrolyte systems.
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quaternary ammonium room temperature ionic liquid including an oxygen atom in side chain Lithium Salt binary electrolytes ionic conductivity and 1h 7li and 19f nmr studies on diffusion coefficients and local motions
2008Co-Authors: Kikuko Hayamizu, Shiro Seki, Seiji Tsuzuki, Yasutaka Ohno, Hajime Miyashiro, Yo KobayashiAbstract:A room-temperature ionic liquid (RTIL) of a quaternary ammonium cation having an ether chain, N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethylsulfonyl)amide (DEME-TFSA), is a candidate for use as an electrolyte of Lithium secondary batteries. In this study, the electrochemical ionic conductivity, σ, of the neat DEME-TFSA and DEME-TFSA-Li doped with five different concentrations of Lithium Salt (LiTFSA) was measured and correlated with NMR measurements of the diffusion coefficients D and the spin−lattice relaxation times T1 of the individual components DEME (1H), TFSA (19F), and Lithium ion (7Li). The ion conduction of charged ions can be activated with less thermal energy than ion diffusion which contains a contribution from paired ions in DEME-TFSA. In the doped DEME-TFSA-Li samples, the σ and D values decreased with increasing Salt concentration, and within the same sample generally DLi < DTFSA < DDEME except for the sample having the lowest Salt concentration at low temperatures. Sin...
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quaternary ammonium room temperature ionic liquid including an oxygen atom in side chain Lithium Salt binary electrolytes ionic conductivity and 1h 7li and 19f nmr studies on diffusion coefficients and local motions
2008Co-Authors: Kikuko Hayamizu, Shiro Seki, Seiji Tsuzuki, Yasutaka Ohno, Hajime Miyashiro, Yo KobayashiAbstract:A room-temperature ionic liquid (RTIL) of a quaternary ammonium cation having an ether chain, N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethylsulfonyl)amide (DEME-TFSA), is a candidate for use as an electrolyte of Lithium secondary batteries. In this study, the electrochemical ionic conductivity, sigma, of the neat DEME-TFSA and DEME-TFSA-Li doped with five different concentrations of Lithium Salt (LiTFSA) was measured and correlated with NMR measurements of the diffusion coefficients D and the spin-lattice relaxation times T1 of the individual components DEME (1H), TFSA (19F), and Lithium ion (7Li). The ion conduction of charged ions can be activated with less thermal energy than ion diffusion which contains a contribution from paired ions in DEME-TFSA. In the doped DEME-TFSA-Li samples, the sigma and D values decreased with increasing Salt concentration, and within the same sample generally DLi
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imidazolium based room temperature ionic liquid for Lithium secondary batteries effects of Lithium Salt concentration
2007Co-Authors: Shiro Seki, Kikuko Hayamizu, Yasutaka Ohno, Hajime Miyashiro, Yo Kobayashi, Akira Usami, Yuichi Mita, Hiroyuki Tokuda, Masayoshi Watanabe, Seiji TsuzukiAbstract:To understand the basic properties of Lithium secondary batteries which consist of nonflammable and nonvolatile room-temperature ionic liquid electrolytes, we examined the ionic conductivity, electrolyte/electrode interfacial resistance, and charge-discharge rate characteristics by varying the Lithium Salt concentration in the room-temperature ionic liquid, Lithium Salt binary electrolytes. By using a modified imidazolium cation-based room-temperature ionic liquid as an electrolyte, the Lithium secondary batteries achieved a stable charge-discharge operation of more than 100 cycles (cathode LiCoO 2 , anode Lithium metal, voltage region 3.0-4.2 V, current density 1/8 C). Moreover, we found that an optimal Lithium Salt concentration exists for obtaining an excellent battery rate performance, which depends on delicate balances in several factors, such as ionic conductivity (viscosity), interfacial resistances at the LiCoO 2 cathode/electrolyte interface, and the Lithium metal anode/electrolyte interface.