Development of High-Performance and Safe Next-Generation All-Solid-State Na Batteries

在过去的几十年里，与化石燃料消费相关的全球能源短缺已成为一个主要问题，导致对替代清洁能源的需求。锂离子电池已经被开发出来，是最有前途的储能系统之一，特别是在便携式电子产品甚至电动汽车(EV)中。然而，对锂的巨大需求依赖于锂资源的可获得性，而锂并不被视为地壳中的丰富元素。不幸的是，锂化合物的成本在过去几年里也迅速增加，导致锂离子电池的价格上涨。由于钠的丰度高、成本低、氧化还原电位合适，钠电池被认为是传统锂离子电池的理想替代品和补充，特别是在大规模储能应用方面。在不同的钠电池系统中，固态钠电池(SSNBs)是最有前景的候选电池，它通过将易燃液体电解液替代为不可燃固态电解液(SSE)而具有高能量密度和高安全性。然而，目前SSNBs的发展仍然主要受到界面现象和其他关键的基本科学技术问题的限制。这项拟议研究计划的长期目标是应用纳米技术和纳米材料来应对高能量密度、安全和低成本的下一代固态钠电池的挑战。该研究计划建立在材料设计和合成、机理理解、电池设备制造等几个方面的基础上。长期目标将通过以下两个主题的短期目标来实现：i)合成高离子导电性、良好的空气稳定性和电极相容的硫化物基钠SSE；ii)合成新的卤化物基Na SSE；iii)通过原子层沉积(ALD)/分子层沉积(MLD)稳定电极与SSE之间的界面；iv)无阳极电极设计；以及v)深入了解SSNBs中的界面化学。拟议项目的成功完成将通过向加拿大能源和纳米技术行业转移新知识、专业知识和技术，加快固态钠电池的开发，并直接减少环境污染，为加拿大工业和纳米技术界带来好处。此外，两名MESc学生和三名博士生将接受培训，为快速增长的电动汽车市场的关键职位做好准备，这将有助于缓解电池领域不可避免的当地熟练人才严重短缺的问题。

Over the past decades, the global energy shortage related to the consumption of fossil fuels has become a major concern leading to the demand for alternative clean energy sources. Li-ion batteries (LIBs) have been developed and are one of the most promising energy storage systems, particularly for portable electronics and even electrical vehicles (EVs). However, the enormous demand for LIBs are dependent on the availability of Li resources, and Li is not regarded as an abundant element in the Earth's crust. Unfortunately, the costs of Li compounds have also rapidly increased in the past years, resulting in increased prices for LIBs. Due to the high abundance, low cost, and suitable redox potential of sodium (Na), Na batteries are considered as the ideal alternatives and complementarity to conventional Li-ion batteries (LIBs), especially for large-scale energy storages application. Among different Na batteries systems, solid-state Na batteries (SSNBs) are the most promising candidates due to the high energy density and high safety by replacing the flammable liquid electrolytes into non-flammable solid-state electrolytes (SSEs). However, the current development of SSNBs is still mostly limited by interfacial phenomena and other key basic scientific and technical issues. The long-term objective of this proposed research program is to apply nanotechnology and nanomaterials to address the challenges for next-generation solid-state Na batteries with high energy density, safety, and low cost. The research program builds on a couple of aspects of materials design and synthesis, mechanism understanding, battery device fabrication. The long-term objective will be achieved through the following short-term objectives in two themes: i) synthesis of high ionic conductive, good air stability, and electrode compatible sulfide-based Na SSEs; ii) synthesis of new halide-based Na SSEs; iii) stabilization of the interface between electrodes and SSEs by atomic layer deposition (ALD)/molecular layer deposition (MLD); iv) anode-free electrode design; and v) deep understanding of the interface chemistry in SSNBs. Successful completion of the proposed project will provide benefits to Canadian industry and the nanotechnology community by transferring new knowledge, expertise, and technologies to Canadian energy and nanotechnology industries, by accelerating the development of solid-state Na batteries and by directly reducing the environmental pollution. Furthermore, two MESc students, and three PhD students will be trained and prepared for key positions in the fast-growing EV market, which will help alleviate the inevitable critical shortage of skilled local personnel in the battery field.