Kemijska in elektrokemijska analiza komercialnih litij-ionskih baterijskih celic

Herman, Jošt (author), Genorio, Boštjan (mentor)

Kemijska in elektrokemijska analiza komercialnih litij-ionskih baterijskih celic V novem tisočletju vedno bolj spoznavamo, da fosilna goriva niso več vzdržen vir energije . Eden izmed največjih porabnikov energije in fosilnih goriv je sektor mobilnosti, zato se v napredek na tem področju vlaga veliko truda. Enega izmed najobetavnejših energijskih medijev za osebna vozila prihodnosti predstavljajo litij-ionske baterije, katerih razvoj trenutno uživa velik razcvet. Največja prednost uporabe hranilcev elektrike za pogon vozil je trenutno ta, da vire onesnaženja, ki so posledica sežiga fosilnih goriv umaknemo iz urbanih področij. Dodatna prednost je, da s tem dosežemo centralizacijo izpustov onesnažil, zaradi česar je mogoče izvajati učinkovitejše čiščenje ali celo zajem izpustov onesnažil in toplogrednih plinov. V prihodnosti se pričakuje, da bo elektrifikacija vozil omogočila postopen prehod na 'zelene' vire energije, ki energijo proizvajajo v obliki elektrike. Eden izmed prevladujočih pristopov v razvoju zmogljivejših baterijskih celic je višanje deleža niklja v katodnih aktivnih materialih. [1, 2] Iz tega razloga smo v naši raziskovalni skupini na začetku naredili pregled razpoložljivih komercialnih baterijskih celic in izmed le-teh za našo reprezentativno testno celico izbrali LG HG2 formata 18650, katere katodni material vsebuje velik delež niklja. Poleg tega je izbrana celica ustreznega formata, ki omogoča relativno preprosto elektrokemijsko karakterizacijo na razpoložljivih merilnih napravah. V magistrski nalogi je predstavljenih nekaj osnovnih elektrokemijskih analiznih tehnik, s katerimi smo pridobili podatke o odzivu celic na simulirano električno obremenitev in obrabo. Opisani so tudi postopki in pristopi, s katerimi izboljšamo natančnost, ponovljivost in varnost izvedenih meritev. Na poseben izziv smo naleteli pri odpiranju trdih ohišij cilindričnih celic, kar je potreben vmesen korak za pridobitev vzorcev aktivnih komponent (elektrod) komercialnih celic za namen nadaljnje kemijske in fizikalne analize. V ta namen smo izdelali več pripomočkov in razvili ustrezne praktične postopke, ki so podrobneje opisani v tem delu.

• Language: Slovenian
• Keywords: litij-ionske baterije, komercialne celice, analiza komponent
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: FKKT - Faculty of Chemistry and Chemical Technology
• Year: 2021
• PID: 20.500.12556/RUL-124414
• COBISS.SI-ID: 48259843
• Publication date in RUL: 20.01.2021

Secondary language

• Language: English
• Title: Chemical and electrochemical analysis of commercial lithium-ion battery cells

Abstract

Chemical and electrochemical analysis of commercial lithium-ion battery cells In this new millennium, we are beginning to realize that fossil fuels aren't a sustainable energy source anymore. One of the biggest consumers of energy and hydrocarbon fuels is the sector of electromobility, which is thus seeing some of the biggest efforts toward improvement. One of the most promising energy media for personal transport of the future are lithium-ion batteries, whose development is currently on the rise. The biggest benefit of the use of electrochemical storage devices in vehicles is, that we can move the sources of pollution, which result from burning of the fossil fuels, out of urban areas. Additional benefit comes from centralization of pollution sources, because of which better pollutant control and even greenhouse gas uptake is possible. In the future it is expected that vehicle electrification will enable a gradual transition to 'green' sources of energy, which output energy in the form of electricity. One of the prevailing trends in the development of higher performance batteries is the increase in nickel concentration in cell cathodic materials. [1, 2] Because of this, our research group conducted a research of available commercial cells and selected LG HG2 cell in 18650 cylindrical format as our representative test cell which contains nickel rich cathodic material and is appropriate for testing on our existing machines because of its format. In the continuation of this work, I have presented some basic analytical techniques, with which we have obtained information about the response of the cells to simulated wear. I have also described methods and contraptions that we use to improve the accuracy, repeatability and safety of our measurements. We have encountered a special problem, when opening the hard cell housings, which is needed for obtaining the samples of the active cell components for various chemical and physical analysis. To this end, we have constructed several accessories and procedures, which are described in this work.

• Keywords: lithium-ion batteries, commercial cells, component analysis