Graphene enabled next generation battery technology

The project aims to develop a graphene enable sodium ion battery. There are several markets for rechargeable batteries
and these can the segmented into 1. The 3C or consumer electronic Market, 2. Power tools and applicances 3.
Automotives, 4. Industrial including stationary energy stroage. SHARP sell products in all of these markets excepting the
automotive market. The sodium ion battery (NIB) is being developed as a low cost alternative rechargeable battery
technology. It is expected that NIB could directly replace lithium ion batteries (LIB) in all of the established and emerging
markets and lead acid batteries (PbA) in the low cost applications. The direct substitution of a highly developed and
optimised LIB technology for established applications will be time consuming and difficult to displace. SHARP are
interested in the emerging markets, such as stationary energy storage, where there is no currently established energy
storage technology and the development of new technologies will involve demonstrators and hence new technologies can
also be established. This project will focus on developing electrodes for a new NIB technology for longer life and higher
volumetric densities specifically for residential and community energy storage systems. In particular for coupling PV local
renewable energy generation sources with local energy storage systems. The advantages of this system are to provide a
greater self sufficiency to consumers, and to buffer an intermittent energy generation thus providing a greater stablity
between the grid and the property.
Current alternative technologies for stationary energy storage include lead acid batteries (PbA) and lithium ion (LIB). Whilst
lead acid batteries are significantly lower cost than lithium ion their life-time is significantly lower, therefore the life time
costs of these technologies are similar. Sodium ion batteries (NIB)offer a lower cost alternative to LIB however NIB
batteries have not yet been commercialised as further development is required to optimise cycle life and performance
properties, specifically for the stationary energy storage markets. The addition of graphene into the electrodes is expected
to improve the electronic transport properties of the electrodes improving the current distribution, the packing density, and
hence the volumetric energy and performance properties of the cell.

There are several benefits, that the resultsing graphene enabled NIB will deliver. By having a solar panel and energy
storage system in the home, the consumer will have a greater awareness off the local energy generation and usage in their
home, leading to greater energy self-sufficiency. It is highly likely that in the future, with 17% of electricity in the UK being
generated by wind, there will be periods of intermittency and electricity companies may charge security of supply
premiums. By having an energy storage device in the home this will mitigate against short intermittencies in the grid and
allow for fluctuations in supply. On a larger community level, storing the electricity in people's homes removes the need to
vast infrastructure and substation upgrades for increased electricity transmissions during hours of strong sunlight or other
excess renewable generation. It can also help towards peak demand management by using the electricity generated locally
during the day in the evening when generation is not possible and there is greater demand. On a larger scale; electricity
companies could use domestic storage as part of the distribution network, and with smart meters could this could be
monitored, controlled and balanced. The Environmental benefits include less requirement for fossil fuel-powered spinning
reserve which is necessary to maintain a stable grid, increased renewable energy generation, and less peak energy
generation all of these lead to lowering CO2 emissions, and reduced losses from transmission (9-11%) due to the energy
being generated and stored locally. The emergence of a different market for energy storage will stimulate R&D in
alternative technologies and away from expensive lithium ion and the short lived lead acid batteries, and create a
momentum for developing new electrochemical energy storage which are currently optimised for either the automotive
Industry or the portable electronics market rather than the alternative markets which have different energy storage
requirements.
The impact on our need to reduce CO2 emissions should also be considered. The incorporation of an ES device will lower
UK carbon emissions with estimated savings of 27 k tonnes CO2 in 2015.