In this paper, commercial lithium ion battery cells consisting of graphite based anode and LiNi0.80Co0.15Al0.05O2 (NCA) oxide based cathode were investigated regarding their aging behavior. The capacity loss is depend...In this paper, commercial lithium ion battery cells consisting of graphite based anode and LiNi0.80Co0.15Al0.05O2 (NCA) oxide based cathode were investigated regarding their aging behavior. The capacity loss is dependent on the state of charge (SOC) whereas the battery is operated with partial cycles at defined SOCs. The structural change of the positive electrode material is identified as dominating aging process. Especially grid services such as primary control reserve are of economic interest for battery system operators. In this application, small charge and discharge cycles are the main operation mode. Considering the operation of single battery storage systems in a virtual storage power plant, different states of charges are much more of interest. Thus the battery aging behavior of lithium ion cells with NCA based cathode material with respect to cycling at specific state of charge with small depth of discharge (DOD) is investigated. The results in this paper provide understanding of small DOD cycling at given SOC behavior which is necessary for NCA lifetime prediction in this particular case, especially in virtual storage plant with various storage systems and thus various SOCs for delivery primary reserve the small DOD behavior which has an important impact on efficiency and economy. It is a key finding, which aging mechanisms are essential in order to optimize the cell operation and adapt it to system performance.展开更多
While redox flow batteries carry a large potential for electricity storage,specifically for regenerative energies,the current technology-prone system-the all-vanadium redox flow battery-exhibits two major disadvantage...While redox flow batteries carry a large potential for electricity storage,specifically for regenerative energies,the current technology-prone system-the all-vanadium redox flow battery-exhibits two major disadvantages:low energy and low power densities.Polyoxometalates have the potential to mitigate both effects.In this publication,the operation of a polyoxometalate redox flow battery was demonstrated for the polyoxoanions[SiW_(12)O_(40)]^(4-)(SiW_(12))in the anolyte and[PV_(14)O_(42)]^(9-)(PV14)in the catholyte.Emphasis was laid on comparing to which extent an upscale from 25 to 1400 cm^(2) membrane area may impede efficiency and operational parameters.Results demonstrated that the operation of the large cell for close to 3 months did not diminish operation and the stability of polyoxometalates was unaltered.展开更多
文摘In this paper, commercial lithium ion battery cells consisting of graphite based anode and LiNi0.80Co0.15Al0.05O2 (NCA) oxide based cathode were investigated regarding their aging behavior. The capacity loss is dependent on the state of charge (SOC) whereas the battery is operated with partial cycles at defined SOCs. The structural change of the positive electrode material is identified as dominating aging process. Especially grid services such as primary control reserve are of economic interest for battery system operators. In this application, small charge and discharge cycles are the main operation mode. Considering the operation of single battery storage systems in a virtual storage power plant, different states of charges are much more of interest. Thus the battery aging behavior of lithium ion cells with NCA based cathode material with respect to cycling at specific state of charge with small depth of discharge (DOD) is investigated. The results in this paper provide understanding of small DOD cycling at given SOC behavior which is necessary for NCA lifetime prediction in this particular case, especially in virtual storage plant with various storage systems and thus various SOCs for delivery primary reserve the small DOD behavior which has an important impact on efficiency and economy. It is a key finding, which aging mechanisms are essential in order to optimize the cell operation and adapt it to system performance.
文摘While redox flow batteries carry a large potential for electricity storage,specifically for regenerative energies,the current technology-prone system-the all-vanadium redox flow battery-exhibits two major disadvantages:low energy and low power densities.Polyoxometalates have the potential to mitigate both effects.In this publication,the operation of a polyoxometalate redox flow battery was demonstrated for the polyoxoanions[SiW_(12)O_(40)]^(4-)(SiW_(12))in the anolyte and[PV_(14)O_(42)]^(9-)(PV14)in the catholyte.Emphasis was laid on comparing to which extent an upscale from 25 to 1400 cm^(2) membrane area may impede efficiency and operational parameters.Results demonstrated that the operation of the large cell for close to 3 months did not diminish operation and the stability of polyoxometalates was unaltered.
