The UK Energy Storage Supergen Consortium
Prof Peter Hall
Dept Chemical Engineering
University of Strathclyde
Glasgow
Scotland
Need for Energy StorageEven though UK energy grid is based upon
centralised power sources there is considerable energy storage built into systemCoal stocks peaked at 24,000 kTonnes at end of 2009
(~55,000 GWh electrical)Pumped hydro only accounts for equivalent of 3,500
Tonnes coalElectrification of transport will double electrical
demand and have immediate effect on CO2 emissions
Supergen partnershipSix Universities:
Fundamental materials understanding: Cambridge, Bath
Materials, device production: St Andrews, Strathclyde, Newcastle
Materials scale-up: Oxford, StrathclydeTransport engineering: StrathclydeGrid engineering: Bath
Technology problem areasHigh cost/low energy density of Li based
batteriesMost supercapacitors manufacturers
base technology around organic liquid electrolytesLow voltage devices (~6-7 V)High production costsTechnology awareness and applications
Anode
LiCathode
O2Organic Electrolyte
Li+
O2
Li2O2
Carbon Electrode
2Li+ + 2e- + O2 Li2O2
Li battery research Li/O2 cells
Vtotal = 1.434 cm3/gSBET = 1725 m2/gPS = 5.60 nm
Vtotal = 1.320 cm3/gSBET = 1545 m2/gPS = 6.10 nm
Vtotal = 1.150 cm3/gSBET = 1290 m2/gPS = 6.15 nm
Capacity of Li ion batteries
Increased capacity
Li/O2 battery performance
Charge / Discharge cycling of ACRF003-950 carbon
Supercapacitor researchDevelopments to increase
performance/cost ratio includeAqueous electrolyte devices based on high
grade carbonsIonic liquid based supercapacitors Development of pseudocapacitors
Future developments are materials based
I n d i a U r b a n D r i v e C y c l e , b a t t e r i e s o n l y
- 1 0 0
- 5 0
0
5 0
1 0 0
1 5 0
2 0 0
2 5 0
3 0 0
0 1 0 0 2 0 0 3 0 0 4 0 0 5 0 0 6 0 0 7 0 0 8 0 0 9 0 0
T i m e ( s )
Battery Current (A)
I n d i a U r b a n D r i v e C y c l e , o p t i m i s e d f o r b a t t e r y l i f e t i m e
- 1 0 0
- 5 0
0
5 0
1 0 0
1 5 0
2 0 0
2 5 0
3 0 0
0 1 0 0 2 0 0 3 0 0 4 0 0 5 0 0 6 0 0 7 0 0 8 0 0 9 0 0
T i m e ( s )
Battery Current (A)
Battery lifetime extension
Materials structure/performance
0
0.5
1
1.5
2
2.5
3
0 200 400 600 800 1000
Time (s)
Vo
lta
ge
(V
)
ACRF200ACRF300ACRF500ACRF750
Sample 2
mA
4
mA
8
mA
16
mA
32
mA
64
mA
Emax
Wh/g
EMImBF4 Capacitance F/g
ACRF200 170.1 148.9 137.4 128.9 120.9 113.95 2231.9
ACRF300 147.6 141.0 136.2 126.95 123.25 116.5 1845
ACRF500 113.1 106.3 101.8 97.7 92.7 88.8 1413.8
ACRF750 77.6 71.4 66.2 60.3 53.7 46.6 1024.7
Conclusions/PlansSubstantial materials developments have taken
placeRechargeable Li/O2 cells have been
demonstrated at the button cell levelOur aim is to produce viable pouch cells
within three yearsFundamental improvements have been made to
the understanding of mass transfer in ionic liquid based supercapacitorsWe aim to produce commercial aqueous
bipolar supercapacitors within two years
www.energystorage.org.uk