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## The study of heterocomposite electrolyte preparation by in-situ method

### Małgorzata Stempień

#### Abstract

Introduction Battery industry are of the most growing sectors of the global economic market. Introduced by Sony, the first commercial lithium-ion cells are essential to improve and modify the technology aimed at improving their properties (eg. capacity, cycle life). These modifications apply to both electrodes and electrolytes with different additives improving their properties. Also, the miniaturization and scaling up with increasing battery capacity is desirable due to the increasing interest in electric vehicles with lithium-ion batteries. Result and discussion The aim of this study was to develop a methodology for the preparation of electrolytes based on methylalumoxane (MAO) heterocomposite system, using the in-situ method and to investigate their properties. The advantages of this method was ability to produce a thin, uniform layer of electrolyte directly on the surface of the lithium electrode. MAO is the organometallic compound, which acts similar to the ceramic fillers purpose of. Adding this type of compound is to improve the properties exhibited by the electrolyte, especially to achieve the increase in ionic conductivity and better mechanical properties. Subject of the research was chosen as a cross-linked electrolyte being substituted methylalumnoxane, with monofunctional poly (ethylene glycols) (PEGME) with variety chain lengths (average molecular weight 300 and 750), and containing a lithium salt (LiCF3SO3). It underwent a number of studies have demonstrated its properties. For comparison the same measurements were performed in two branched electrolytes with different numbers of substituted monofunctional poly (ethylene glycols) having an average molar mass of compound 750 to methylalumoxane (MAO ratio to PEGME is 1:6 and 1:10). Each sample underwent the same series of tests: the stability of passivation layers, ion conductivity, measurements of the lithium transfer number, cycling and diffusion measurements. In addition, cross-linked electrolyte layer deposited on a lithium electrode was subjected to Raman spectroscopy study. Conclusion Analyzing the studies found that it is possible to produce very thin, uniform layer of electrolyte on the lithium electrode surface using in-situ method. Produced membrane is susceptible to mechanical damage during preparation of the cell. Mapping results using Raman spectroscopy confirmed that the electrolyte layer is very thin and homogeneous with uniformly distributed salt. However, during the conduct of the other studies showed inferior properties compared with branched electrolytes embedded in the separator, among others they have a lower number of transfer of cations and are too unstable for a long time of polarization. Perhaps the improvement of the properties will be using other electrode materials than pure metallic lithium.
Record ID
WUTcf82ce8cc4d042beb03814c2367feb91
Diploma type
Master of Science
Author
Małgorzata Stempień Małgorzata Stempień,, Undefined Affiliation
Title in Polish
Badanie przygotowania elektrolitów heterokompozytowych metodą in-situ
Supervisor
Maciej Siekierski (FC/CofIC) Maciej Siekierski,, Chair Of Inorganic Chemistry (FC/CofIC)Faculty of Chemistry (FC)
Certifying unit
Faculty of Chemistry (FC)
Affiliation unit
Chair Of Inorganic Chemistry And Solid State Technology (FC/CofIC)
Study subject / specialization
, Technologia Chemiczna
Language
(pl) Polish
Status
Finished
Defense Date
17-01-2012
Issue date (year)
2012
Keywords in Polish
-
Keywords in English
-
Abstract in Polish
urn:pw-repo:WUTcf82ce8cc4d042beb03814c2367feb91