Amélioration du comportement électrochimique des batteries plomb-acide à usage photovoltaïque

Texte intégral accessible uniquement aux membres de l'Université de LorraineIn an isolated photovoltaic system, the accumulator is the weak point of the device. His charge capacity is closely related to the conduction properties of the grid/PAM interface, interface which evolves according to the state of charge. The positives grids, made with a Pb-Ca-Sn alloy, play the role of both collector of current and support of the positive active mass. At ambient temperature, these alloys are prone to metallurgical transformation, which is followed by a drop of the mechanical properties and by a reduction of the corrosion resistance whatever the charge conditions are. The use of a heat treatment makes it possible to durably maintain alloy in the state in which the best behaviors are observed. The addition of tin in the alloy, associated to the heat treatment, allows to improve the properties of material more. Moreover the tin, like silver and rare earth, plays an essential role in the formation and the growth of the lead oxides, but on the properties of adherence of the corrosion layer during the tests of cycling too.Dans un système photovoltaïque, la batterie est le point faible de l'installation. Sa capacité de recharge est liée aux propriétés de conduction de l'interface grille/MA positive, interface qui évolue en fonction de l'état de charge. Les grilles positives sont en alliages Pb-Ca-Sn et ont le double rôle de collecteur de courant et de support de la MA. A température ambiante, ces alliages sont sujets à des changements d'états métallurgiques qui s'accompagne d'une chute des propriétés mécaniques et d'une diminution de la résistance à la corrosion quelque soit les conditions de charges rencontrées. L'application d'un traitement thermique permet de maintenir durablement l'alliage dans l'état garant des meilleurs comportements. L'ajout d'étain à l'alliage, associé à un traitement thermique, permet d'améliorer encore les propriétés mécaniques du matériau. Par ailleurs, l'étain, comme l'argent, le lanthane et le cérium, influence la formation et la croissance des oxydes de plomb mais aussi l'adhérence de la couche de corrosion dans des conditions de cyclage

Amélioration du comportement électrochimique des batteries plomb-acide à usage photovoltaïque

Dans un système photovoltaïque, la batterie est le point faible de l'installation. Sa capacité de recharge est liée aux propriétés de conduction de l'interface grille/MA positive, interface qui évolue en fonction de l'état de charge. Les grilles positives sont en alliages PbCaSn et ont le double rôle de collecteur de courant et de support de la MA. A température ambiante, ces alliages sont sujets à des changements d'états métallurgiques qui s'accompagne d'une chute des propriétés mécaniques et d'une diminution de la résistance à la corrosion quelque soit les conditions de charges rencontrées. L'application d'un traitement thermique permet de maintenir durablement l'alliage dans l'état garant des meilleurs comportements. L'ajout d'étain à l'alliage, associé à un traitement thermique, permet d'améliorer encore les propriétés mécaniques du matériau. Par ailleurs, l'étain, comme l'argent, le lanthane et le cérium, influence la formation et la croissance des oxydes de plomb mais aussi l'adhérence de la couche de corrosion dans des conditions de cyclage.In an isolated photovoltaic system, the accumulator is the weak point of the device. His charge capacity is closely related to the conduction properties of the grid/PAM interface, interface which evolves according to the state of charge. The positives grids, made with a PbCaSn alloy, play the role of both collector of current and support of the positive active mass. At ambient temperature, these alloys are prone to metallurgical transformation, which is followed by a drop of the mechanical properties and by a reduction of the corrosion resistance whatever the charge conditions are. The use of a heat treatment makes it possible to durably maintain alloy in the state in which the best behaviors are observed. The addition of tin in the alloy, associated to the heat treatment, allows to improve the properties of material more. Moreover the tin, like silver and rare earth, plays an essential role in the formation and the growth of the lead oxides, but on the properties of adherence of the corrosion layer during the tests of cycling too.NANCY1-SCD Sciences & Techniques (545782101) / SudocSudocFranceF

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