A TEM study of morphological and structural degradation phenomena in LiFePO₄-CB cathodes:Morphological and structural degradation in LiFePO4-CB cathodes

LiFePO4-based cathodes suffer from various degradation mechanisms which influences the battery performance. In this paper morphological and structural degradation phenomena in laboratory cathodes made of LiFePO4 (LFP) mixed with carbon black (CB) in an 1 mol L-1 LiPF6 in EC:DMC (1:1 by weight) electrolyte are investigated by transmission electron microscopy (TEM) at various preparation, assembling, storage and cycling stages. High-resolution TEM (HRTEM) imaging shows that continuous SEI layers are formed on the LFP particles and that both storage and cycling affects the formation. Additionally loss of CB crystallinity, CB aggregation and agglomeration is observed. Charge-discharge curves and impedance spectra measured during cycling confirm that these degradation mechanisms reduce the cathode conductivity and capacity.Comment: 5 figures, 2 table, journal article in International Journal of Energy Research, 201

Policies on the move: The transatlantic travels of Tax Increment Financing

Growing influence of the “new mobilities paradigm” among human geographers has combined with a long and rich disciplinary tradition of studying the movement of things and people. Yet how policy ideas and knowledge are mobilized remains a notably under-developed area of inquiry. In this paper, we discuss the mobilization of policy ideas and policy models as a particularly powerful type of mobile knowledge. The paper examines the burgeoning academic work on policy mobilities and points towards a growing policy mobilities approach in the literature, noting the multidisciplinary conversations behind the approach as well as the key commitments of many of its advocates. This approach is illustrated using the travels of Tax Increment Financing (TIF) with the role of learning and market-making within efforts to spread TIF to more cities highlighted. In conclusion, we discuss some of the political and practical limits that often confront efforts to mobilize policy ideas