Addressing the Instability of High Capacity Lithium Battery Cathodes
Although xLi2MnO3·(1-x)LiMO2 electrodes maintain their capacity when repeatedly charged to high potetials (>4.5 V), structural changes result in voltage decay and hysteresis during repeated charge/discharge cycles, repressing their use in commercial battery products. The structural decay has been attributed to the irreversible migration of transition metal ions (predominantly Mn) into the lithium-depleted layers. This disadvantage is being addressed by slightly reducing the lithium content in parent xLi2MnO3·(1-x)LiMO2materials to introduce ‘pillaring’ transition metal ions in the lithium layers of the composite structure.
This presentation will discuss the background and versatility of composite electrode structures and highlight the opportunity that these materials present for overcoming voltage fade, with a specific focus on composite ‘layered-spinel’ electrode structures.
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