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Caractérisation et vieillissement de composants supercondensateurs hybrides : étude sous contrainte de températures négatives
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The work of this Ph.D. thesis focuses on the study and the electrical characterization of "Lithium-ion Capacitors LIC" or hybrid supercapacitors. LICs are electrical energy storage components resulting from an internal hybridization between a lithium-ion battery LIB and a conventional supercapacitor EDLC. Their characterization is divided into two parts. The first part studies fresh LIC cells, with time and frequency measurements over a wide operating temperature range. This will allow to draw Nyquist and Ragone diagrams and to establish equivalent models for the cells. The second part aims to deepen the characterization by applying specific aging methods on LIC cells in order to observe the evolution of their behavior and performance over time. To complete the existing work in the literature, the choice of the aging temperature was based on two negative ambient temperatures. The results of these tests make it possible to develop aging laws that aim to predict the end of life of the storage components in the case of an industrial electrical vehicle application.The manuscript is divided into four chapters. The first one is devoted to the presentation of LICs but also lithium-ion batteries and supercapacitors, their proper characteristics being necessary for the understanding of LICs dynamic behavior.The second chapter studies fresh LIC cells in order to situate them physically from their energetic performances between lithium-ion batteries and supercapacitors according to the results of temporal and frequency characterizations. The tests are applied at different temperatures in order to observe the difference in behavior according to positive and negative temperatures.The third chapter presents the calendar aging of LICs, where no current constraint is applied, for two different negative temperatures, -10°C and -30°C. The result then allows the observation of the evolution of the cells over time in case of storage or at rest time.Finally, the fourth and last chapter studies the cycling aging of LICs during the application of an HEV car starter-booster current cycle, for the same negative ambient temperatures. These tests, under fairly severe conditions, make it possible to observe the limits of LICs and to predict their end of life with appropriate aging laws.