Beyond Li-ion Batteries: Novel, Efficient Electrode Materials for Sodium Ion Storage

迫切需要开发一种高效，低成本的替代品来取代现在无处不在的锂离子电池。缺乏高性能电极材料是向市场推出新技术的主要挑战，该技术的成本效益远远高于锂离子电极。本项目旨在开发、研究和验证新型、稳定和经济的钠离子电池电极。合理化电池材料电化学性能的关键是确定离子存储主体并定义材料的局部结构和微观结构稳定性。与此同时，为了预测电极的倍率性能，必须对离子传输进行可靠的评估。本项目（BLESS）提出的系统研究始于合成具有改善的导电性和增强的电化学稳定性的新型阴极和阳极材料。阴极将由具有不同碳含量的溶胶-凝胶衍生的Na 3V 2（PO 4）3/碳纳米复合材料组成。Pickering乳液辅助的溶胶-凝胶合成的新路线将确保复合物的均匀性，从而增强跨电极的电子传输。“一锅法”原位合成的多孔锡阳极嵌入在导电碳和稳定的陶瓷基体（Sn/C/SiOC）将允许容纳锡的体积变化，保持其高Na-storage capacity.The电极材料的电气和微观结构的性能将通过电化学阻抗谱（EIS），23 Na固态MAS NMR光谱，和电子显微镜（SEM/TEM）进行分析。活性材料的固有Na扩散特性将仅通过本项目中开发的单颗粒测量（SPM）进行评估。低电阻阴极复合材料将允许提高Na基电池的倍率性能。通过揭示电极材料的结构变化和离子迁移率，MAS NMR光谱可以帮助深入了解电化学过程背后的化学过程，从而提高电池性能。电子显微镜将允许深入了解复合电极材料的结构以及形成复合材料的内涂层和外涂层的碳质材料的排列。高容量NIB电极材料的开发以及认识和提出有效的解决方案将是稳定钠离子的进一步开发和潜在应用的里程碑在材料工程和电化学方面的知识和经验，以及获得高度专业化的设备（TEM，MAS-NMR，SPM），是成功实现BLESS内计划研究所必需的。拟议的合作为合作伙伴带来了巨大的利益，没有一个团队能够单独实现项目目标。

There is an urgent need to develop a highly efficient, low-cost alternative to the now ubiquitous lithium-ion batteries. The lack of high-performing electrode materials is the main challenge in introducing a new technology to the market, which can be by far more cost-effective than Li-ion-based electrodes. This project aims to develop, investigate and characterise novel, stable and cost-efficient electrodes for Na-ion battery (NIB). The key to rationalise the electrochemical performance of battery materials is to determine the ion storage host and to define the local structure and microstructural stability of the material. In parallel, the ionic transport must be reliably assessed in order to predict the rate performance of the electrode.The systematic study proposed in this project (BLESS) starts with the synthesis of novel cathode and anode materials with improved electrical conductivity and enhanced electrochemical stability. The cathode will consist of sol-gel derived Na3V2(PO4)3/carbon nanocomposite with varying carbon content. The novel route of Pickering emulsion assisted sol-gel synthesis will ensure the homogeneity of the composite resulting in enhanced electron transport across the electrode. "One-pot" in-situ synthesis of porous tin anode embedded in a conductive carbon and stabilised in a ceramic matrix (Sn/C/SiOC) will allow to accommodate the volume changes of tin preserving its high Na-storage capacity.The electrical and microstructural properties of the electrode materials will be analysed by electrochemical impedance spectroscopy (EIS), 23Na solid state MAS NMR spectroscopy, and electron microscopy (SEM/TEM). The intrinsic Na-diffusion properties of the active material solely will be assessed by means of a single-particle measurement (SPM) developed within this project. The low-resistance cathode composite will allow for enhancement of the rate capability of Na-based cells. By revealing the structural changes and the ion mobility of the electrode materials, MAS NMR spectroscopy can help to deeply understand the chemistry behind the electrochemical processes and therefore improve the battery performance. Electron microscopy will allow to get insights into the structure of composite electrode materials as well as the arrangement of carbonaceous materials creating inner and outer coating of the composite.Developing new, compatible, high capacity electrode materials for NIB in line with recognising and proposing the efficient solutions to counteract their drawbacks will be a milestone for the further development and potential application of stable sodium ion batteries.The knowledge and experience in materials engineering and electrochemistry, as well as access to highly specialised equipment (TEM, MAS-NMR, SPM), is required for the successful realisation of the planned studies within BLESS. The proposed cooperation generates enormous benefits for the partners, and none of the teams can alone achieve the project objectives.