Novel manufacturing approaches to smarter Na-ion cathodes

钠比锂更丰富，成本更低，钠离子电池的阴极配方比锂离子电池对Co等成本挥发性元素的依赖程度更低。然而，对于钠离子技术来说，与锂离子竞争，至关重要的是要尽可能充分地实现其固有的储能特性。该项目将研究新的制造方法对具有竞争力的钠离子电池的作用和贡献。该方法基于智能“结构化”电极，利用合理设计、控制电极孔隙度和固体成分的空间排列，例如通过增材制造制造的新型分层或分级电池电极。我们已经开发出新的制造方法，可以在微米尺度上控制离子电池电极中的局部活性、碳和粘合剂分数。我们已经证明这种方法可以降低锂离子电池的降解率，并改善功率特性。然而，观察到的改进的潜在原因尚未完全合理化和捕获到一般的理解，最终将支持优化电极结构的先验设计。这将是该项目的一个关键目标，基于首次研究将这些结构设计方法应用于钠离子电池可能获得的性能优势。我们将研究结构钠离子阴极提供的性能权衡范围如何提供优于当前锂离子性能的领域。特别是，Na离子在固定电网规模的储能应用中可能具有特殊的优势，我们将研究如何通过结构电极方法放大这些优势。该项目还将研究新型无溶剂或“干燥”工艺在钠离子电池中的应用。这种方法为电极结构提供了新的机会，在这种方法中，湿浆铸造和干燥被控制剪切和固态电极成形过程所取代。消除溶剂型处理提供了显著的成本、安全性和新的阴极化学可能性，并可以为更可持续的电池行业做出重大贡献。除了制造科学研究外，该项目还将利用广泛的微结构技术，包括聚焦离子束显微镜和x射线微断层扫描，以及储能性能的电化学测试。还将进行费用比较研究。该项目属于EPSRC能源和脱碳研究领域。

Na is more abundant than Li with lower cost, and cathode formulations for Na-ion batteries are less dependent than Li-ion on cost volatile elements such as Co. However, for Na-ion technologies to compete with Li-ion, it is essential that their intrinsic energy storage properties are realised as fully as possible. This project will investigate the role and contribution that novel manufacturing approaches can make to competitive Na ion batteries. The approach is based on smart "structured" electrodes that make use of rationally-designed, controlled spatial arrangements of electrode porosity and solid constituents, such as new layered or graded battery electrodes fabricated by additive manufacture.We have developed new manufacturing approaches that allow micron-scale control of the local active, carbon and binder fraction in ion battery electrodes. We have shown this approach can reduce Li-ion cell degradation rate, and improve power characteristics. However, the underlying reasons for the observed improvements have not been fully rationalised and captured into generic understanding that will eventually support a priori design of optimised electrode structures. This will be a key aim of the project, based on for the first time, investigating what performance benefits might be achieved by applying these structural design approaches to Na-ion cells. We will study how the range of performance trade-offs provided by structured Na-ion cathodes might provide areas of advantage over current Li-ion performance. In particular, Na ion may have particular advantages in stationary grid scale energy storage applications, and we will study how these advantages can be amplified by the structured electrode approach.The project will also investigate the application of new solvent free, or "dry", processing to Na ion batteries. Novel opportunities for electrode structuring are provided by this approach in which wet slurry casting and drying is replaced by a controlled shear and then solid-state electrode forming process. Elimination of solvent-based processing offers the potential for significant cost, safety and new cathode chemistry possibilities, and can make a significant contribution to a more sustainable battery industry. As well as manufacturing science research, the project will make use of extensive microstructural techniques including focused ion beam microscopy and X-ray micro-tomography, and electrochemical testing of energy storage performance. Cost comparison studies will also be undertaken.This project falls within the EPSRC energy and decarbonisation research area.