Impact of Aqueous and Acidic Treatment on Li-Transition Metal Oxides

锂离子电池（LIB）已成为我们移动的社会的重要组成部分，并被认为是成功过渡到可再生能源的关键。在这一巨大的成功和工业需求之后，大多数针对LIB的研究活动都是应用的，试图克服现有的和剩余的挑战。这些挑战之一是使用水作为阴极的“绿色”电极处理溶剂，因为现有技术的阴极材料对水和湿气高度敏感。因此，世界各地的大量科学家和工程师正试图通过开发新的粘合剂、添加剂和保护涂层来应对这一挑战。然而，据我们所知，迄今为止还没有对这一关键挑战进行基础研究，以实现环境友好的阴极制造过程。在H2O-LiMO中，我们将解决这一问题，并对锂过渡金属氧化物进行深入研究-特别是，LiNi0.5Mn1.5O4（LNMO）作为无钴高能阴极-使用一套全面的高度互补和非常适合的实验技术-高分辨率电子显微镜，结合选择区域电子衍射、（价）电子能量损失谱和电化学，即，分别在乌尔姆大学和乌尔姆亥姆霍兹研究所的两个合作伙伴的关键能力。对颗粒表面发生的过程的既定理解将使我们能够为成功应用添加温和（无机）酸以保护LNMO表面提供基本解释，从而为改善这一重要技术的可持续性铺平道路。

Lithium-ion batteries (LIBs) have become an essential part of our mobile society and are considered key for the successful transition to renewable energy sources. Following this tremendous success and industrial need most research activities towards LIBs is rather applied, trying to overcome the existing and remaining challenges. One of these challenges is the employment of water as “green” electrode processing solvent for the cathode, since state-of-the-art cathode materials are highly sensitive towards water and moisture. Accordingly, a large number of scientists and engineers worldwide is trying to address this challenge by developing new binders, additives, and protective coatings. A fundamental investigation of this key challenge towards an environmentally-friendly cathode fabrication procedure, however, has not been attempted so far to the best of our knowledge.Within H2O-LiMO we will address this issue and conduct an in-depth investigation of lithium transition metal oxides – in particular, LiNi0.5Mn1.5O4 (LNMO) as cobalt-free high-energy cathode – exposed to water using a comprehensive set of highly complementary and excellently suited experimental techniques – high-resolution electron microscopy, coupled with selected area electron diffraction, (valence) electron energy loss spectroscopy, and electrochemistry, i.e., the key competencies of the two partners at Ulm University and at the Helmholtz Institute Ulm, respetively. The established understanding of the processes occurring at the particle surface will then allow us also to provide a fundamental explanation for the successfully applied addition of mild (inorganic) acids to protect the LNMO surface, thus, ideally paving the way for an improved sustainability of this important technology.