Understanding the surfaces of fast charging battery materials: SURF-FAST

在Nyobolt，我们正在开发一种可用于电动汽车和消费品应用的超快速充电锂离子电池，通过缩短充电时间来最大限度地减少停机时间，并重新定义客户对电池使用地点和方式的期望。Nyobolt的超快速充电技术由剑桥大学开发，使用铌钨氧化物（NWO）作为电池阳极材料。传统的锂离子材料通常含有石墨或钛酸锂（LTO）作为阳极，并且存在安全性和性能问题，后者部分是由于它们在整个材料中固有的缓慢锂离子移动。相比之下，NWO使锂离子能够快速移动通过其结构-离子扩散系数比例如，LTO。这是它们能够用于电池中更快充电和更高功率的关键。更重要的是，这些高离子迁移率可以在没有纳米尺寸的情况下实现。这对可持续性产生了重大影响-我们可以避免纳米颗粒的复杂性和成本，而不会影响性能。克莱尔·格雷教授和Sai Shivareddy博士于2019年创立了Nyobolt有限公司，将这一英国知识产权推向市场，并为客户提供快速充电解决方案。在电池单元中，这些阳极（本身是一种复合材料）将与典型的阴极电极配对，并与浸泡在电解质溶液中的隔膜结合。所有这些组件的相互作用以及由此产生的各种表面的变化可能会对电池在运行期间的性能产生重大影响。化学和循环条件的微小变化可能对关键性能指标产生重大影响，例如寿命、速率性能和容量保持率。这也将影响到电池的整体安全性，本项目旨在利用国家物理实验室的技术研究表面的这些变化，这些技术既提供足够的灵敏度，又提供补充信息（例如西姆斯、拉曼、XPS），这些技术目前在Nyobolt的常规研发工作项目中还不容易获得。通过了解表面，我们可以通过在循环过程中改变电池化学或电化学条件来定制解决方案，以提高性能，创造出更好的产品，以超越当前最先进的技术。更好的快速充电电池可以使英国更广泛、更快地采用电动汽车，并更普遍地实现电气化，并有助于英国的净零排放战略。

At Nyobolt, we are working on creating an ultra-fast charging lithium-ion battery that can be used in both electric vehicles and consumer goods applications, minimizing downtime by shortening the recharging period, and reframing customer's expectations about where and how we can use batteries.Developed at the University of Cambridge, Nyobolt's ultra-fast charging technology uses niobium tungsten oxides (NWO) as battery anode materials. Conventional lithium-ion materials typically contain graphite or lithium titanate (LTO) as anodes and suffer from both safety and performance issues, the latter due in part to their inherently slow lithium ion movement throughout the material. In contrast, NWOs enable lithium ions to move rapidly though their structures - with ion diffusion coefficients that are several orders of magnitude higher than those in e.g., LTO. This is the key to their ability to be used for a quicker charge and higher power in a battery. What's more, these high ion mobilities can be achieved without nanosizing. This has a significant impact on sustainability - we can avoid the complexity and cost of nanoparticles without compromising on the performance. Prof. Clare Grey and Dr Sai Shivareddy founded Nyobolt Limited in 2019 to bring this UK IP to market and offer a fast-charging solution to customers.In a battery cell, these anodes (which are themselves a composite material) will be paired with a typical cathode electrode and combined with a separator soaked in an electrolyte solution. The interaction of all these components and the resulting changes to the various surfaces present can have a significant impact on the performance of the battery during its operation. Small changes in the chemistry and cycling conditions can have a big influence on key performance indicators, such as lifetime, rate-performance, and capacity retention. These will also impact the overall safety of the cell.This project seeks to study these changes to the surface using techniques at the National Physical Laboratory which provide both sufficient sensitivity and complementary information (e.g. SIMS, Raman, XPS), which are not currently readily available in routine R&D work programs at Nyobolt.By understanding the surface, we can tailor solutions by changing the battery chemistry or electrochemical conditions during cycling to target improved performance, creating a better product to out-compete current state-of-the-art technology. A better fast-charging battery can enable the wider and faster adoption of electric vehicles in UK and electrification more generally and contribute to the UK's net-zero strategy.