Background to our research

The need to reduce carbon dioxide (CO₂) emissions from the burning of fossils fuels has led to Europe looking towards increasing the development and use of alternative ‘green’ energies. However, electricity supplies gained from, for example, wind, wave and solar power are intermittent as they are dependent upon external factors. As a result the storage of energy produced by these means is now crucial in the levelling out of supply and demand. If such energies are to be used on a larger scale there needs to be a mass market solution, therefore major improvements in stationary energy storage technology are now paramount.

Batteries are one of the main contenders for stationary energy storage with lithium-ion batteries having applications for providing uninterruptible power supply, power quality, transmission, distribution and load shifting. Whilst at the moment energy storage in bulk power management is served by pumped hydro power and compressed air storage, their geographical specific locations may not be the most practical energy storage solution. Batteries now have to demonstrate the ability to store energy efficiently, within certain power, lifetime and safety specifications, at a price-point that is ultimately affordable by the energy industry, before they can be considered for bulk power management.

SIRBATT will address these barriers as follows:

Power – Electrode materials will be designed and synthesised with a nano-scale architecture to allow rapid ion diffusion into the host structure, therefore permitting high discharge/charge cycles.

Lifetime – Improved understanding of the electrode/electrolyte interface and its ageing processes can lead to batteries with great cycle and shelf-life. Key to this development is to identify the actual nature and composition of the solid electrolyte interphase (SEI). The SEI is a protecting layer formed on the negative electrode of lithium batteries as a result of electrolyte decomposition, mainly during the first cycle. Battery performance, irreversible charge “loss”, rate capability, cycle life, calendar life and safety are highly dependent on the quality of the SEI in particular.

Safety – In some respects engineering of the battery pack for stationary applications is less restrictive than for electric vehicles due to the non-requirement to protect the battery from high velocity impact. However due to the scale up – the potential of huge energy release during catastrophic runaway, do lead to the requirement of an exceptional high safety standard. Like lifetime, safety will be greatly enhanced by better understanding and control of passivation layers on battery electrodes and use of micro-sensors to monitor internal temperature and pressure within in cells.

Cost – This will be addressed by the selection of candidate electrode materials that minimise raw material cost by avoiding expensive/rare elements and the investigation of low-cost routes to nanoparticle electrode material synthesis.

The scientific aim of SIRBATT is a radical improvement in the fundamental understanding of the structure and reactions occurring at lithium battery electrode/electrolyte interfaces. This will be achieved through an innovative programme of collaborative research and development.