Ogljiki sintetizirani iz kavnih usedlin kot anodni material v Na-ionskih akumulatorjih

Ihanec, Neva (author), Dominko, Robert (mentor)

Potreba po pridobivanju električne energije izobnovljivih virov energije, kot sta sonce, veter in plimovanje, postaja čedalje pomembnejše. Pridobivanje energije iz obnovljivih virov energije ni konstantno, za shranjevanje električne energije so potrebni stacionarni akumulatorji, za katere so se Na-ionski akumulatorji izkazali kot dobra alternativa Li-ionskim akumulatorjem. Natrija je v zemeljski skorji veliko, kar pomeni nižjo ceno in trajnostno proizvodnjo te zvrsti akumulatorjev. S prenosom znanja o Li-ionskih akumulatorjih je bilo doseženega precej uspeha pri razvijanju katodnega materiala. Za anodni material se v Na-ionskih akumulatorjih ne more uporabljati čisti grafit, ki je standardni material za Li-ionske akumulatorje. V magistrski nalogi sem sintetizirala trdi ogljik iz kavnih usedlin in ga testirala z namenom ugotovitve ustreznosti pri uporabi v Na-ionskih akumulatorjih. Trdi ogljik sem sintetizirala pri različnih temperaturah (900°C, 1200°C, 1400°C in 1600°C). Pridobljeni material sem analizirala z XRD, Raman in SEM. Z analizo sem podala povezavo med temperaturo karbonizacije in strukturo materiala. S pridobljenim materialom sem sestavila testne laboratorijske celice za elektrokemijske meritve. Analiza je potekala po vnaprej določenem programu polnjenja in praznjenja, s katerim sem določila karakteristike shranjevanja natrija v sintetiziranih vzorcih. Glede na analizo strukture materiala in elektrokemijske teste sem ugotovila, da ima trdi ogljik sintetiziran iz kavnih usedlin potencial za uporabo kot anodni material v Na-ionskih akumulatorjih. Struktura materiala sintetiziranega pri 1200°C ima na podlagi analize in elektrokemijskih testov, med testiranimi materiali najboljše lastnosti.

• Language: Slovenian
• Keywords: Na-ionski akumulatorji, anodni material, obnovljivi viri energije, trdi ogljiki
• 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-124415
• COBISS.SI-ID: 48265987
• Publication date in RUL: 20.01.2021

Secondary language

• Language: English
• Title: Carbon materials from spent coffee grounds as anode materials in Na-Ion batteries

Abstract

There is a greater need for the production of electric energy from renewable energy sources like sun, tide and wind every day. Energy from renewable energy sources is produced intermittently and therefore requires a suitable energy storage system to store it. So far, Na-ion batteries have shown potential to be used in stationary energy storage systems instead of Li-ion batteries. Due to the high content of sodium in Earth's crust Na-ion batteries have the potential for low production cost and continuous manufacturing. Transferring the knowledge gained with Li-ion batteries has lead to the development of good cathode materials. Graphite in commercial Li-ion batteries can not be used in Na-ion and this leads to the search of anode material. In this thesis hard carbon was synthesized from spent coffee grounds and was tested to determine the possibility to be used as anode material in Na-ion batteries. Hard carbon was synthesized at different temperatures (900°C, 1200°C, 1400°C and 1600°C). Material was analyzed with XRD, Raman and SEM to show the connection between the temperature of carbonization and the structure of the material. With obtained material testing half cells were assembled for electro-chemical testing, where the cells were charged and discharged repeatedly to determine the behaviour of synthesized material during cycling. Based on structure analysis and electro-chemical test results it was conducted that hard carbon synthetized from spent coffee grounds has the potential for usage in Na-ion batteries. Based on the results, material synthetized at 1200°C shows the best properties.

• Keywords: Na-ion batteries, anode material, sustainable energy, hard carbon