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.
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