Silicijeve nano-čestice kao anodni materijali u litij-ionskim galvanskim člancima

undergraduate thesis

• Title (english): Silicon nano-particles as anodic materials in lithium-ion batteries
• Author: Fran Hrlić
• Mentor: Zoran Mandić (mentor)
• Committee member: Zoran Mandić (predsjednik povjerenstva)
• Committee member: Lidija Furač (član povjerenstva)
• Committee member: Vladimir Dananić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2022-09-07, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

U ovom radu ispitivana su elektrokemijska svojstva nanostrukturiranog silicija sa stajališta primjene kao anodnih materijala za litijske galvanske članke. Aktivne elektrode priređene su kao smjese nanstruktiranog silicija s nanostrukturiranim grafitom i acetilenskim crnilom različitih omjera. Elektrode su testirane metodom cikličke voltametrije i punjenjem/pražnjenjem članka konstantnom strujom. Dobiveni rezultati pokazuju da prisutnost nanostrukturiranog silicija znatno povećava specifični kapacitet postignut tijekom prvog ciklusa pražnjenja članka, ali i da dolazi do znatnog pada istog već u drugom ciklusu pražnjenja. Nadalje, uočeno je da prisutnost nanografita povećava stupanj reverzibilnosti reakcije članka te da odsutnost acetilenskog crnila rezultira vrlo niskim vrijednostima dostignutih struja. Iz dobivenih rezultata zaključuje se da je smjesa nanosilicij/nanografit dostigla najmanje vrijednosti struja te da pokazuje najveći stupanj ireverzibilnosti reakcije. S druge strane, smjesa nanosilicij/acetilensko crnilo dostigla je najveće vrijednosti struja, ali i visok stupanj ireverzibilnosti reakcije, dok je smjesa nanosilicij/nanografit/acetilensko crnilo pokazala najveći stupanj reverzibilnosti reakcije članka, što je svakako neophodna karakteristika suvremenih litij-ionskih članaka.

Abstract (english)

In this work, electrochemical properties of nanostructured silicon were studied for the potential application as anode material for litihium batteries. The electrodes were repared as mixtures of nanostructured silicon with the nanostructured graphite and carbon black in different ratios. Cyclic voltammetry and galvanostatic charging/discharging were used for probing the electrode reactions. The obtained results show that the presence of nanosilicon significantly increases the specific capacity achieved during the first cycle of battery discharge, but also that there is a significant drop in the same during the second cycle of battery discharge. Furthermore, it was detected that the presence of nanographite increases the degree of reversibility of the cell reaction and that the absence of carbon black results in very low values of the reached currents. From the obtained results, it can be concluded that the nanosilicon/nanographite mixture reached the lowest values of currents and that it shows the highest degree of irreversibility of the cell reaction. On the other hand, the nanosilicon/carbon black mixture reached the highest current values, but also a high degree of irreversibility of the cell reaction, while the nanosilicon/nanographite/carbon black mixture showed the highest degree of reversibility of the cell reaction, which is certainly a necessary characteristic of modern lithium-ion batteries.

• Keywords: galvanski članak; litij-ionski galvanski članak; ciklički voltamogrami; krivulje punjenja/pražnjenja; specifični kapacitet; energija; reverzibilnost; nanosilicij; nanografit; interkalacija; legiranje
• Keywords (english): battery; lithium-ion battery; cyclic voltamogram; charge/discharge curves; specific capacity; energy; reversibility; nanosilicon; nanographite; intercalation; alloying
• Language: croatian
• URN:NBN: urn:nbn:hr:149:282588
• Study programme: Title: Applied Chemistry - Undergraduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry; Course: Environmental chemistry and green technologies; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) primijenjene kemije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) primijenjene kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2023-03-01 10:01:39