Solvent-Free Composite PEO-Ceramic Fiber/Mat Electrolytes for Lithium Secondary Cells (original) (raw)

Article Interface Properties between Lithium Metal and a Composite Polymer Electrolyte of PEO18Li(CF3SO2)2N-Tetraethylene

2013

The electrochemical properties of a composite solid polymer electrolyte, consisting of poly(ethylene oxide) (PEO)-lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and tetraethylene glycol dimethyl ether (TEGDME) was examined as a protective layer between lithium metal and a water-stable lithium ion-conducting glass ceramic of Li 1+x+y (Ti,Ge) 2−x Al x P 3−y Si y O 12 (LTAP). The lithium ion conductivity and salt diffusion coefficient of PEO 18 LiTFSI were dramatically enhanced by the addition of TEGDME. The water-stable lithium electrode with PEO 18 LiTFSI-2TEGDME, as the protective layer, exhibited a low and stable electrode resistance of 85 Ω•cm 2 at 60 °C, after 28 days, and low overpotentials of 0.3 V for lithium plating and 0.4 V for lithium stripping at 4.0 mA•cm −2 and 60 °C. A Li/PEO 18 LiTFSI-2TEGDME/LTAP/saturated LiCl aqueous solution/Pt, air cell showed excellent cyclability up to 100 cycles at 2.0 mAh•cm −2 .

Advanced, high-performance composite polymer electrolytes for lithium batteries

Progress in lithium battery technology may be achieved by passing from a conventional liquid electrolyte structure to a solid-state, polymer configuration. In this prospect, great R&D effort has been devoted to the development of suitable lithium conducting polymer electrolytes. The most promising results have been obtained with systems based on blends between poly(ethylene oxide) and lithium salts. In this work we show that the transport and interfacial properties of these electrolytes may be greatly enhanced by the dispersion of a ceramic filler having an unique surface state condition. The results, in addition to their practical reflection in the lithium polymer electrolyte battery technology, also provide a valid support to the model which ascribes the enhancement of the transport properties of ceramic-added composites to the specific Lewis acid-base interactions between the ceramic surface states and both the lithium salt anion and the PEO-chains.

Interface Properties between Lithium Metal and a Composite Polymer Electrolyte of PEO18Li(CF3SO2)2N-Tetraethylene Glycol Dimethyl Ether

Membranes, 2013

The electrochemical properties of a composite solid polymer electrolyte, consisting of poly(ethylene oxide) (PEO)-lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and tetraethylene glycol dimethyl ether (TEGDME) was examined as a protective layer between lithium metal and a water-stable lithium ion-conducting glass ceramic of Li1+x+y(Ti,Ge)2-xAlxP3-ySiyO12 (LTAP). The lithium ion conductivity and salt diffusion coefficient of PEO18LiTFSI were dramatically enhanced by the addition of TEGDME. The water-stable lithium electrode with PEO18LiTFSI-2TEGDME, as the protective layer, exhibited a low and stable electrode resistance of 85 Ω·cm2 at 60 °C, after 28 days, and low overpotentials of 0.3 V for lithium plating and 0.4 V for lithium stripping at 4.0 mA·cm-2 and 60 °C. A Li/PEO18LiTFSI-2TEGDME/LTAP/saturated LiCl aqueous solution/Pt, air cell showed excellent cyclability up to 100 cycles at 2.0 mAh·cm-2.

Advanced, lithium batteries based on high-performance composite polymer electrolytes

Progress in lithium battery technology may be achieved by passing from a conventional liquid electrolyte structure to a solid-state, polymer configuration. In this prospect, great R&D effort has been devoted to the development of suitable lithium conducting polymer electrolytes. The most promising results have been obtained with systems based on blends between poly(ethylene oxide) and lithium salts. In this work we show that the transport and interfacial properties of these electrolytes may be greatly enhanced by the dispersion of a ceramic filler having an unique surface state condition. The results, in addition to their practical reflection in the lithium polymer electrolyte battery technology, also provide a valid support to the model which ascribes the enhancement of the transport properties of ceramic-added composites to the specific Lewis acid-base interactions between the ceramic surface states and both the lithium salt anion and the PEO-chains.

PEO-carbon composite lithium polymer electrolyte

Electrochimica Acta, 2000

The addition of fillers to lithium polymer electrolytes is a well established procedure to improve their mechanical stability as well as their interfacial stability with lithium anodes. As far only inert, non-conductive fillers have been used in the formulation of PEO-based composite electrolytes. In this report as the addition of a small volume fraction (B 1.5%) of moderately high surface area ( 60 m 2 g − 1 ) carbons results in composite lithium polymer electrolytes with excellent performance in terms of conductivity and interfacial stability is shown.

High performance PEO-based polymer electrolytes and their application in rechargeable lithium polymer batteries

Ionics, 2007

Solvent-free, lithium-ion-conducting, composite polymer electrolytes have been prepared by a double dispersion of an anion trapping compound, i.e., calyx(6) pyrrole, CP and a ceramic filler, i.e., super acid zirconia, S-ZrO 2 in a poly(ethylene oxide)-lithium bis(oxalate) borate, PEO-LiBOB matrix. The characterization, based on differential thermal analysis and electrochemical analysis, showed that while the addition of the S-ZrO 2 has scarce influence on the transport properties of the composite electrolyte, the unique combination of the anion-trapping compound, CP, with the large anion lithium salt, LiBOB, greatly enhances the value of the lithium transference number without depressing the overall ionic conductivity. These unique properties make polymer electrolytes, such as PEO 20 LiBOB(CP) 0.125 , of practical interest, as in fact confirmed by tests carried out on lithium battery prototypes.

Nanocomposite polymer electrolytes and their impact on the lithium battery technology

Solid State Ionics, 2000

Lithium polymer electrolytes formed by dissolving a lithium salt LiX in poly(ethylene oxide) PEO may find useful application as separators in lithium rechargeable polymer batteries. The main problems which are still to be solved for a complete successful operation of these materials are the reactivity of their interface with the lithium metal electrode and the decay of their conductivity at temperatures below 708C. In this paper we demonstrate that a successful approach for overcoming these problems is the dispersion of selected, low-particle size ceramic powders in the polymer mass with the aim of developing new types of nanocomposite PEO-LiX polymer electrolytes characterized by enhanced interfacial stability as well as by improved ambient temperature transport properties.

Characteristics of lithium-ion-conducting composite polymer-glass secondary cell electrolytes

Journal of Power Sources, 2002

A family of lithium-ion-conducting composite polymer-glass electrolytes containing the glass composition 14Li 2 O-9Al 2 O 3-38TiO 2-39P 2 O 5 (abbreviated as (LiAlTiP) x O y) with high ionic conductivity, an excellent electrochemical stability range, and high compatibility with lithium insertion anodes is described. An optimized composition has a room temperature conductivity of 1:7 Â 10 À4 S cm À1 , an Li þ transference number of 0.39, and an electrochemical stability window to þ5.1 V versus Li/Li þ. It also has good interfacial stability under both open-circuit and lithium metal plating-stripping conditions and provides good shelf-life.