Thermodynamics and kinetics for stabilization of conversion-type electrodes for LIB based on nano 3d transition metal oxide composites

根据转换机理而非插入反应的电极材料由于具有较高的理论比容量和电荷密度，在新型锂电池方面具有很大的发展潜力。但是，必须首先解决循环稳定性差的问题。特别是，了解转化机制和材料形成过程中第一次反应与随后的氧化还原循环之间差异的原因对于促进电极稳定化的进一步进展至关重要。提出了两种稳定策略，这两种策略都是基于添加选定的元素形成金属氧化物纳米复合材料。这些额外的元素要么在化学上稳定电极材料，要么有助于在电极内或电极处形成导电网络。这个非常复杂的问题的解决方案只有通过将四个研究小组的互补专业知识相互联系才能实现，这些研究小组将在以下领域开展工作：(1)含纳米氧化物的可变3d过渡金属的合成和电化学表征（“与原子一起玩”）；(2)电化学反应第一和第二循环的理论和实验热力学研究；(3)对电化学处理过程中微观结构变化的描述和解释；(4)新电解质成分的开发。子项目（2-4）将研究在(1)中合成的合成材料。（1-4）的迭代结果将为所开发材料更好的循环稳定性带来新的概念。

The electrode materials reacting according to the conversion mechanism instead of intercalation have a large potential for new Li battery aspects due to their high theoretical specific capacity and charge density. However, the problem of bad cycling stability must be solved first. In particular, the understanding of the conversion mechanism and the reasons for the difference between the first reaction during the materials formation and the following oxidation-reduction cycles is essential to stimulate a further progress in the stabilization of the electrodes. Two stabilization strategies are proposed that are based on the addition of selected elements forming metal-oxide nanocomposites. The additional elements should either stabilise the electrode material chemically or contribute to the formation of electrically conductive networks in or at the electrode. The solution of this very complex problem is only possible via interlinking the complementary expertises of four research groups that will work in the fields of (1) the synthesis and electrochemical characterisation of variable 3d transition metal containing nanooxides (“playing with atoms”), (2) the theoretical and experimental thermodynamic investigation of the electrochemical reaction in the first and second cycle, (3) the description and explanation of the changes in microstructure during this electrochemical treatment, and (4) the development of new electrolyte components. The sub-projects (2-4) will investigate selected synthesized materials synthesized within (1). The iteratively achieved results of of (1-4) will cause new concepts for better cycling stability of the developed materials.