Fire protection of lightweight EV battery cases using nanotechnology (PFP_Nano)

在新冠肺炎封锁期间，公路和航空运输的减少导致空气明显更清洁，并使许多人评估运输对我们呼吸的空气的影响。汽车、公共汽车、火车和飞机的电力推进支持向低排放交通的过渡。这些应用的电池选择是锂离子电池（LIB）。为了安全使用，电池组必须保持在规定的电压和温度范围内；损坏（事故、快速减速等）、外部温度过高、充电过快、过度充电或制造缺陷都可能超出限制。化学反应可能会在内部触发，导致短路或温度升高，从而导致热失控和lib着火。因此，需要尽可能长时间地提供锂离子电池防火，以帮助汽车、船舶、铁路和航空航天部门的乘员撤离。大多数LIB外壳由金属（钢，铝）制成，为电池提供机械支撑。这些电池外壳通常很重；更轻的版本可以使用碳纤维增强聚合物（CFRP）制造，并且已经开发了几个原型CFRP电池盒。然而，目前还没有将轻质碳纤维复合材料结构电池盒与内部防火相结合的解决方案。HIVE是一家以创新为基础的企业，开发具有巨大增长和扩大潜力的颠覆性复合材料技术。Hive有一种基于碳纳米管（CNT）的解决方案，可以加入树脂和/或部署在结构CFRP的表面，通过显着提高防火和导热性，同时保持结构性能，赋予多功能。当涂层在复合材料上时，初步测试表明母体材料的点火时间增加了一倍。复合材料的导热性也将得到改进，以更好地管理电池的热。碳纳米管材料在基体内或复合电池外壳表面的重量将使整体复合电池外壳增加几克，但有可能使电池火灾的遏制时间增加一倍，从而以最小的重量和成本为乘员增加被动安全性。因此，与金属版本相比，复合电池外壳的使用将减少电池组的整体重量。该项目将开发一种具有成本效益的被动防火材料系统，用于使用独特格式的碳纳米管（CNT）材料的复合电池外壳，并将生成数据来证明这些材料的性能，以便在多个运输部门实施。

The reduced road and air transport during the COVID lockdown resulted in visibly clearer and cleaner air and has made many assess the impact of transport on the air that we breathe. Electric propulsion for cars, buses, trains, and planes supports the **transition** to **lower emission** transport. The battery of choice for these applications are Lithium Ion Batteries (LIB). For safe use, the battery packs must be maintained within a defined voltage and temperature window; limits can be exceeded by damage (accidents, rapid deceleration etc), excessive external temperatures, charging too quickly, overcharging or manufacturing defects. Chemical reactions may be triggered internally leading to a short circuit or increase in the temperature which can lead to thermal runaway and the LIBs catching fire. Hence, there is a need to provide lithium ion battery fire containment for as long as possible to aid occupant evacuation in auto, marine, rail and aerospace sectors.Most LIB casings are made from metal (steel, aluminium) providing mechanical support to the cells. These battery casings are typically heavy; lighter versions can be made using carbon-fibre-reinforced polymers (CFRP) and several prototype CFRP battery cases have been developed. However, there are no known solutions that combine lightweight CFRP structural battery cases with intrinsic fire containment.HIVE is an innovation-based business developing disruptive composite materials technologies with significant potential for growth and scale-up. Hive have a carbon-nanotube (CNT) based solution that can be incorporated into resins and/or deployed on the surface of structural CFRP to impart multi-functionality through significantly improved fire and thermal conductivity whilst maintaining structural performance. When coated on a composite material, preliminary tests have shown the time to ignition of the parent material is doubled. Thermal conductivity of the composite materials will also be modified for better thermal management of the batteries. The weight of the CNT materials either within the matrix or on the surface of the composite battery cases will add a few grammes to the overall composite battery case but has the opportunity to double the containment time for a battery fire, thereby adding passive safety for occupants at minimal weight and cost. Use of composite battery cases will therefore reduce overall battery pack weight compared with metallic versions.This project will develop a **cost-effective passive fire protection material system** for composite battery cases using a unique format of Carbon nanotube (CNT) materials and will generate the data to demonstrate the performance of these materials for implementation across multiple transport sectors.