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Akumulatory litowe jako współczesne systemy magazynowania energii

Bakierska M., Chojnacka A.

Wiadomości Chemiczne

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2014

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[Z] 68, 9-10

856--871

EN

Due to the need for comprehensive management of energy resources, the storage of energy becomes an increasingly important issue. From the analysis of the advantages and drawbacks of all methods of energy storage, reversible electrochemical cells seem to be the most effective. Among them, rechargeable lithium batteries are characterized by high energy density (Fig. 1), high voltage and good cyclic stability [7]. Thus, they have been a dominant technology of energy storage systems for over a decade. It is expected that market demand for Li-Ion cells in the coming years will grow at a rapid rate, as a result of their widespread use inter alia in portable electronic devices such as mobile phones, smartphones, tablet PCs and laptops (Fig. 2) [9]. This article presents the characteristics of lithium batteries. The most commonly used cathode material in Li-Ion battery is layered cobalt oxide (130 mAh/g). However, it is expensive and toxic material, thus manganese-based compounds (LiMnO2, LiMn2O4), polyanionic olivine structured materials (LiFePO4) and silicates Li2MSiO4 (M = Mn, Co, Fe) gain an increasing interest. Due to the presence of two lithium ions in the structure of silicates, these materials have a high theoretical capacity, reaching about 300 mAh/g (Tab. 2) [1, 7–9, 11, 12]. Commercially used anode material is graphite (372 mAh/g). Nevertheless, scientists are still looking for new anode materials with a higher gravimetric capacity. Researches are primarily focused on modifications of the graphite or the use of lithium alloys with other elements (Sn, Al, Si) (Tab. 3) [1, 9, 12, 14, 15]. In the Lithium-Ion cells only non-aqueous solutions are used in the character of electrolytes. As a best material, the inorganic electrolyte lithium salts (such as LiBr, LiAsF6, LiPF6, LiBF4, etc.) soluble in organic solvents are used [1, 2, 7, 8]. However, the study on alternative solutions (polymer electrolytes) is very important. Continuous technological progress makes the research on improving the reversible electrochemical cells necessary to fulfill the expectations of users in order to improve the quality of their lives.

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Analiza termiczna – podstawy, zastosowanie oraz porady praktyczne – cz. I

Zaitz M. M., Bakierska M.

Laboratorium - Przegląd Ogólnopolski

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2013

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nr 7-8

58--61

PL

Analiza termiczna, jako grupa metod analitycznych, umożliwia pomiar zmian szeregu właściwości fizycznych i chemicznych materiałów w funkcji temperatury i czasu. Dzięki różnorodności jej odmian stanowi niezwykle przydatne narzędzie badawcze oraz znajduje szerokie zastosowanie w wielu dziedzinach nauki, a w szczególności w analizie chemicznej substancji.

EN

Thermal analysis is a group of analytical methods which are capable of measuring changes in a number of physical and chemical properties of materials as a function of temperature and time. Because of the diversity of its variety it is an extremely useful research tool and it can find broad applications in many fields of science, and in particular in the chemical analysis of substances.

3

Analiza termiczna – podstawy, zastosowanie oraz porady praktyczne – cz. II

Zaitz M. M., Bakierska M.

Laboratorium - Przegląd Ogólnopolski

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2013

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nr 9-10

58--61

PL

Analiza termiczna - jako grupa metod analitycznych - umożliwia pomiar zmian szeregu właściwości fizycznych i chemicznych materiałów w funkcji temperatury i czasu. Dzięki różnorodności jej odmian stanowi niezwykle przydatne narzędzie badawcze oraz znajduje szerokie zastosowanie w wielu dziedzinach nauki, a w szczególności analizie chemicznej substancji.

EN

Thermal analysis is a group of analytical methods which are capable of measuring changes in a number of physical and chemical properties of materials as a function of temperature and time. Because of the diversity of its variety is an extremely useful research tool and it can find broad applications in many fields of science, and in particular in the chemical analysis of substances.