Advanced battery condition monitoring in electric and hybrid vehicles

A key part of reducing CO2 emissions from vehicles will be the increased electrification of transport through battery electric vehicles and hybrid vehicles. Lithium-ion based chemistries surpass all other rechargeable cells in terms of energy per unit weight and per unit volume and this makes them particularly attractive in vehicle applications. However, the battery is one of the most expensive parts in an electric power-train and therefore it is imperative to ensure that it lasts as long as possible. Battery durability is a significant challenge to commercialisation, and a key way to improve battery durability is to ensure proper management of the cells during use. To this end, battery condition monitoring is vital for the uptake of low carbon vehicles. However, currently available on-vehicle battery monitoring systems use diagnostic methods that are limited to an uncertain estimation of battery state of charge and state of health and provide little information about internal electrochemical processes. The proposed research will develop a much improved condition monitoring system which is not only able to measure state of charge accurately but can also measure cell degradation processes, and predict and prevent cell failure in advance, whilst using the existing drive-train components present in an electric or hybrid vehicle, adding as little additional hardware as possible.

This project is specifically aimed at developing an innovative online, under-load technique which provides vital information about battery conditions in an electric or hybrid vehicle, information that cannot currently be measured using available battery management systems. As we have noted in the proposal, such a device could be integrated with other vehicle systems such as the motor controller(s), giving a cost, weight and space saving. This could be applied in every battery electric and hybrid electric vehicle on the road. Hence this research has direct applicability to all those in the automotive sector interested in the current and/or future electrification of vehicles, be they in pure electric or hybrid form, supporting key aspects of the UK low carbon industrial strategy. As also noted in the proposal, in our work at Imperial College we benefit from strong relationships with a number of key industry partners in this sector, both large and small, such as Jaguar Land Rover, Lotus, Nissan, Frazer-Nash, Radical, Caterpillar and Toyota. We therefore have good opportunities to ensure that this work makes the maximum possible impact with these companies, and with others in the sector. The project team will meet to review the overall project direction with industrial collaborators every six months to ensure that our overall research aims are meeting the requirements of the automotive sector. Given our view that the innovation proposed in this proposal could have significant commercial impact, we will first ensure that the necessary IP is protected by patents, filed through Imperial Innovations. We have already approached Imperial Innovations with respect to the proposed innovation, and they have not identified any prior IP in their searches to date. Prof. Brandon will be responsible within the project for ensuring that the correct IP strategy is followed - he has a track record in the development and exploitation of IP arising from EPSRC funded activity, having founded and developed Ceres Power into a >100M Imperial spin out company over the past 8 years. Once IP is protected (which we anticipate will be done within the first couple of months of the project) we will then engage in discussions with industry partners under appropriate non-disclosure agreements to protect IP sensitive material. Our aim will be ensure that Imperial is in a position to exploit the innovation through partnership between Imperial Innovations and automotive companies and/or their supply chain. Subsequent to patent filing, non-confidential outputs from the project will be widely disseminated via peer reviewed publication, presentations at major international conferences such as EVS25, the 25th World Electric Vehicle Symposium and Exposition, Nov 5-9th 2010, China, and the UK low carbon vehicle partnership, of which Imperial is an active participant. We will also ensure that appropriate research outputs and learning are disseminated through our Energy Futures Lab (EFL - www.imperial.ac.uk/energyfutureslab) and in particular through the Energy Futures Labs electric and hybrid vehicle network (www3.imperial.ac.uk/energyfutureslab/research/researchnetworks/electricandhybridvehicles). We enjoy strong links into the Greater London Assembly, (the Mayor has publicly committed to electric and low carbon vehicles for London), Transport for London, and the Department for Transport Office for Low emission vehicles, and we will use these to disseminate our work in this area in both the London and national context. Similarly, given our close proximity to Westminster, we frequently brief senior Government ministers and advisers on low carbon transport and the energy sector, and again this provides a mechanism to disseminate the high level impact of our work.