The Advanced Lead-Acid Battery Technological Breakthrough 100,000 mile test Performance Enhanced through Creativity run achieved by Dramatic improvements in the performance of lead-acid batteries have The Ultrabattery at come about not through the use of rare or expensive materials, but through Millbrook Proving the creative use of the raw materials that lead-acid manufacturers have Ground in England. been using for decades. 12 Performance exceeds It is the creative use of standard, readily available materials that has enabled 2 engineers to achieve the technological breakthroughs thatControl are cell making a new Ultrabattery Ni-MH battery used in 10.5 hybrid electric vehicles. generation of affordable, effi cient and environmentally-safeCut-off voltage for Lead-acid lead-acid cell and battery batteries 1.7 available for use in hybrid electric vehicles and9 other energy storage programs. Surpasses standards 1.4 Quite simply, the addition of certain types of carbon to the traditional lead-acid design has led to the set for power-assist 7.5 production of the new ‘Ultrabattery’ that is breaking performance standards and is positioned to HEVs by the United States 1.1 become the low-cost alternative to batteries produced with nickel metal hydrideNi-NiMH cell (Ni-MH) or lithium (Li-Ion) -discharge voltage/V Department of Energy’s 6 -discharge voltage/V technology. In the ‘Ultrabattery’ a supercapacitorCut-off electrode voltage for Ni-NiMH cellcomposed of carbon is combined with FreedomCAR Program. 0.8 End-of the lead-acid battery negative plate in a single4.5 cell to better regulate the fl ow (charge and discharge) End-of of energy, thereby extending the power and life of the battery itself. UltraBattery research 3 0.5 has created a low cost, In more conventional designs of lead–acid battery0 also,40,000 the incorporation80,000 of120,000 the same160,000 ingredient, 200,000 high power device that carbon, has sharply reduced the accumulation of lead sulfate depositsCycle Numberthat previously inhibited the delivers suffi cient energy performance of lead-acid batteries. and has a long service-life. Carbon + Supercapacitor = Performance Breakthrough For years, scientists have known that Separator Separator Pb the accumulation of lead sulfate has i i1 i _ i2 prevented lead-acid batteries _ _ _ + from achieving a sustained level of op- + + eration required for heavy duty perfor- Combined mance in hybrid electric vehicles and other energy storage applications. Carbon Carbon PbO Pb PbO2 2 PbO2 Electrode This problem would occur whenever Electrode Lead-acid Cell Asymmetric Supercapacitor Ultrabattery a lead-acid battery’s ‘state-of-charge’ remained signifi cantly below 100% for a sustained period. Conversely, whenever the battery’s state-of-charge would rise much above 70 percent, it could not accept a recharge from either a stop-start braking system or a charge from the engine itself. Inserting a supercapacitor into the battery 12 2 acts as a ‘buffer’ to manage the high-rate Control cell Ultrabattery charge/discharge process so that the unit 10.5 Cut-off voltage for Lead-acid cell and battery 1.7 can operate within a state-of-charge window below 70 percent successfully. 9 1.4 Deployment of the carbon in a supercapacitor 7.5 electrode attached to the negative plate Ni-NiMH cell 1.1 -discharge voltage/V has resulted in the creation of the Ultrabattery, 6 -discharge voltage/V Cut-off voltage for Ni-NiMH cell produced by the Furukawa Battery Co. of 0.8 End-of 4.5 End-of Japan and the Commonwealth Scientifi c and Industrial Research Organisation (CSIRO) 3 0.5 of Australia and tested by the Advanced 0 40,000 80,000 120,000 160,000 200,000 Cycle Number Lead-Acid Battery Consortium (ALABC) which is headquartered in North Carolina. For More Information The Advanced Lead-Acid Battery Consortium Suite 100, 2525 Meridian Parkway The chart to the left shows the performance of three batteries over 200,000 HEV (hybrid electric vehicle) Durham, North Carolina, 27713 USA cycles. The fi rst, in blue, is a “control” cell without the supercapacitor or other carbon additions. The Tel: 919.361.4647 Fax: 919.361.1957 second,Separator in green, is theSeparator Ultrabattery with the added supercapacitori Pb electrode. The third, in orange, is a i1 standard Ni-MH cell. i _ i2 www.alabc.org _ _ _ + + + Printed on 100% Recycled Paper Combined Carbon Carbon PbO Pb PbO PbO2 2 2 Electrode Electrode Lead-acid Cell Asymmetric Supercapacitor Ultrabattery.