Electric vehicles are quiet, energy efficient and non-polluting at the point of use. The electricity to power them can be produced from a variety of fuels, some of them low carbon – and one way of storing the energy is in the form of batteries...

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With its interest in environmental technologies and expertise in materials science, Johnson Matthey is getting involved in this technology that enables transport that makes fewer demands on the environment. Through its Axeon subsidiary, which joined the group in October 2012, Johnson Matthey is developing the advanced electric vehicle batteries that will power these cars. It had already been running battery material R&D programmes at its Technology Centre in Sonning Common, UK, exploring novel energy storage materials for next generation batteries, but through Axeon – which has key skills in the design and manufacture of lithium-ion battery systems – it now has greater resources, with an electrochemistry team in Dundee, UK for advanced engineering and prototype manufacturing, and a site in Gliwice, Poland as a full manufacturing base.

Effective Battery Design

The battery for an electrified vehicle (EV) is sophisticated and technologically complex. Its design involves a multidisciplinary project team covering electrochemistry, electronics, electrical engineering, mechanical engineering, software engineering, system integration and cooling systems. The cells provide the power in the battery, and lithium-ion cells have greater energy density than previous chemistries, making automotive applications much more viable. Other major components are the electronic software and the hardware system or Battery Management System (BMS), which controls and manages the cells – and, in short, ensures safety and performance.

Effective battery design requires detailed understanding of the end application (what is the drive cycle of the vehicle, what energy inputs will be required?) and of cell chemistry, so that our R&D teams can determine the most appropriate form and chemistry of the cell. Axeon is 'cell agnostic': it is independent of cell suppliers, which enables it to choose the best cell for a particular application, and gives it access to newer cell chemistries in advance of commercialisation.

Mechanical engineering is an important part of the process. Vehicles vibrate when they are in motion, so the battery must be effectively packaged within the vehicle (usually with tight space constraints) to ensure that it can safely survive the vibrations and is crash resistant. Thermal management of the cells – heating or cooling them – may also be required, particularly for high power applications like supercars. This keeps the cells in optimum condition for performance and reliability.

Working with Customers

In this field, the supplier must work closely with vehicle manufacturers to provide the battery system each manufacturer requires for each project, produced to exacting quality standards. Axeon has proved that it is fit to supply batteries to the very best, with a customer list that includes Rolls-Royce, Land Rover and Jaguar. For Rolls-Royce, it provided the world's largest passenger car traction battery for the Phantom Experimental Electric prototype, capable of delivering a range of up to 200km and acceleration from 0–60mph in fewer than eight seconds. For Land Rover South Africa, Axeon has developed a battery for a full electric vehicle that will run almost silently in a game park.

If low emission, even zero emission, vehicles are to become a reality, reliable and affordable batteries are essential. Johnson Matthey's strengths in the design of advanced materials and Axeon's expertise in the applications engineering of battery systems can make a strong contribution to a cleaner, less polluted planet.