Chemical Vapour Deposition for Advanced Lithium-Ion Battery Materials and Supercapacitors

电动汽车在全球日益增长的存在被视为运输业脱碳的积极解决方案。因此，化学家和材料科学家正致力于开发可用作下一代电池和超级电容器改进电极和电解液的骨干材料。这项研究将专注于通过使用化学气相沉积(CVD)和原子层沉积(ALD)等非视线沉积技术来产生被认为是下一代电池一部分的材料。这将提供机会来生产明确定义的电流收集器和薄膜。通过所选择的方法，可以微调复合材料的微观结构、形态和化学成分，以克服电池材料面临的潜在挑战，如充电过程中的体积变化和电极的机械、化学或电化学退化。重点将集中在潜在的锂或钠硫化物插层或转换型电极，或电解液材料，如硫化锂、磷酸锂和锂反钙钛矿，以及它们的钠对应物。最初阶段将涉及分子的合成，这些分子可用作CVD和ALD的前体材料，然后将通过一系列方法进行表征，包括X射线衍射、核磁共振和元素分析。将对热分解进行评估，并对前体生成薄膜的能力进行评估。这些薄膜将使用扫描电子显微镜进行表征，并将根据其作为电荷载体的能力进行评估。将利用所选技术(CVD和ALD)的优势来改进电池性能。这些包括在表面沉积均匀的层以防止化学降解的能力，将共形活性材料沉积到结构骨架上的能力，如纳米管、薄片或棒。这项工作的另一个好处是，通过适当选择前体材料、改变沉积参数和化学掺杂，可以对新材料的化学计量比进行高度控制，以适应电池的性能。这项工作的成果将寻求提供适合用作沉积前体的新材料。然后，这些前驱体将生成一种可用作电荷载体的薄膜。这项工作的影响将导致CVD或ALD条件的优化，以便对薄膜进行调整，以提高其作为电极或电解液材料的性能。预期的结果将是产生可用作电极或电解液材料的合适的薄膜。进一步的成果可能包括实现产生化学结构的新方法，这些结构可以在以后的沉积应用中使用。这项研究是与先进汽车推进系统(AAPS)CDT一起进行的，并与他们的“推进电气化”研究主题相关。

The ever-growing global presence of the electric vehicle is seen as a positive solution to decarbonise the transport industry. As a result, chemists and material scientists are aiming to develop materials that can be used as a backbone for improved electrodes and electrolytes for next-generation batteries and supercapacitors.The research will focus on the generation of materials that are considered to be part of the next generation of batteries through the use of non-line-of-sight deposition techniques, including chemical vapour deposition (CVD) and atomic layer deposition (ALD). This will provide opportunities to produce current collectors and thin films that are well-defined. Through the methods chosen, the microstructure, morphology and chemistry of the composites can be finely-tuned to overcome potential challenges that battery materials face, such as volume changes during charging and the mechanical, chemical or electrochemical degradation of the electrodes. Focus will be drawn to potential lithium- or sodium-chalcogenide intercalation or conversion type electrode, or electrolyte materials, such as Lithium sulfides, lithium phosphates and lithium anti-perovskites, and their sodium counterparts. The initial stages will involve the synthesis of molecules that can be used as precursor material for CVD and ALD, which will then be characterised via a host of methods, including X-ray diffraction, NMR and elemental analysis. The thermal decomposition will be assessed, as will the ability of the precursor to create a thin film. The thin films will be characterised using scanning electron microscopy and will be assessed on its ability as a charge carrier. The advantages of the chosen techniques (CVD and ALD) will be exploited to improve upon cell performance. These include the ability to deposit uniform layers on a surface which can be used as a protection against chemical degradation, the ability to deposit conformally active materials onto structured backbones, such as nano-tubes, -flakes or -rods. There is also the advantage of high levels of control over stoichiometry of new materials that will be tailored to suit the cell performance by appropriately choosing the precursor materials, changing the deposition parameters and through chemical doping.The output of this work will seek to provide new materials that are suitable for use as a deposition precursor. These precursors will then generate a thin film which can be used as a charge carrier. The impact of this work will result in an optimisation of conditions for CVD or ALD, so that the thin film can be tuned to offer an improved performance as an electrode or electrolyte material.The intended outcomes would be the generation of suitable thin films that can be used as electrode or electrolyte materials. Further outcomes could include the realisation of novel ways to produce chemical structures that could be later used in the deposition applications. This research is carried out in conjunction with the Advanced Automotive Propulsion Systems (AAPS) CDT and holds relevance to their "Propulsion Electrification" research theme.