Elektrokemijske lastnosti celuloznih kompozitov v litijevih akumulatorjih

diplomsko delo

Grega Venturini (Author), Robert Dominko (Mentor)

Abstract

Kovinski litij je idealni material za anodo v akumulatorjih, saj ima najnižji elektrokemijski potencial in najvišjo teoretsko dosegljivo kapaciteto. Visoka reaktivnost kovinskega litija in dendritska rast med procesom polnjenja sta v preteklosti omejevala njegovo uporabo. Z ustrezno zaščito kovinskega litija bi lahko premostili omenjeni težavi in utrli pot komercialni rabi litij-kovinskih akumulatorjev. Eden izmed obetavnih zaščitnih materialov je celulozni kompozit, ki je sestavljen iz modificirane nano-fibrilirane celuloze in litijevega nitrata, ki zapolni praznine med celuloznimi vlakni. Z uporabo elektrokemijske impedančne spektroskopije smo določili, da mehanizem prenosa litijevih ionov preko kompozitne plasti poteka v skladu s principom elektrolita topilo v soli. Kot ustrezno topilo smo identificirali tetraetilen glikol dimetil eter (TEGDME), katerega masa je morala biti manjša od mase litijevega nitrata v celuloznem kompozitu.

Keywords

akumulatorji;litij;elektroliti;celulozni zaščitni sloj;elektrokemijska impedančna spektroskopija;diplomska dela;

Data

Language:	Slovenian
Year of publishing:	2020
Typology:	2.11 - Undergraduate Thesis
Organization:	UL FKKT - Faculty of Chemistry and Chemical Technology
Publisher:	[G. Venturini]
UDC:	621.355:661.728(043.2)
COBISS:	27974915
Views:	428
Downloads:	111
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	Electrochemical properties of cellulose based composites in lithium batteries
Secondary abstract:	Metallic lithium is an ideal anode material for secondary batteries because it has the lowest electrochemical potential and the highest theoretical specific capacity. The high reactivity of metallic lithium and the formation of dendrites on repeated charging have so far prevented its use. With suitable protection it has the potential to become commercially viable in many different areas. A promising protective material is a cellulose-based composite material consisting of modified nanofibrillated cellulose and lithium nitrate that fills pores created by cellulose fibers. Using electrochemical impedance spectroscopy, we have found that lithium ion migration through the composite protective layer of cellulose follows the concept of solvent-in-salt electrolyte. We identified tetraethylene glycol dimethyl ether (TEGDME) as a suitable solvent. To show conductive properties, the mass of lithium nitrate in the cellulose protective layer had to be higher than the mass of TEGDME.
Secondary keywords:	battery;lithium;cellulose protective layer;electrochemical impedance spectroscopy;
Type (COBISS):	Bachelor thesis/paper
Study programme:	1000373
Thesis comment:	Univ. v Ljubljani, Fak. za kemijo in kemijsko tehnologijo, UNI Kemija
Pages:	35 str.
ID:	12027636