These slides use concepts from my (Jeff Funk) course entitled analyzing hi-tech opportunities to analyze how the economic feasibility of kinetic energy recovery systems is slowly becoming better through improvements in batteries, hydraulic pumps, and flywheels. Many of these systems are currently used in Formula 1 race cars because they enable these cars to achieve higher acceleration and longer times between pit stops. For consumers, flywheels may become the energy storage technology of choice for vehicles particularly as improvements in carbon nanotubes and graphene occur. The rates of improvement for energy and power storage densities for batteries have been very slow and those of flywheels have been much faster. One of the reasons for the rapid improvements in the densities for flywheels is that improvements in the strength per weight of materials have enabled faster rotations and the storage densities are a function of rotation velocities squared. As shown in the slides, carbon fiber has about four times the strength to weight ratio and seven times the energy density of glass. Since carbon nanotubes have strength to weight ratios 15 times higher and graphene has ones 30 times higher than do carbon fiber, energy storage densities of 120,000 kJ/kg or 33.6 kWh are possible with graphene. This energy density is about 100 times higher than is currently available from lithium-ion batteries.

1. MT5009 Analyzing Hi-technology Opportunities Group Project
2012-2013, SEM 2
Team Members
Ding Chao A0098500H
Lin Nan A0023807L
Pan Yunru A0105848Y
Xu Mingjie A0082051U
Zhang Mingqi A0028028L
Zhu Jing A0082009M
For information on other new technologies that are becoming economically feasible, see http://www.slideshare.net/Funk98/presentations

2.  Technology Introduction
 Three Main Categories
 Electrical KERS
 Mechanical KERS
 Hydraulic KERS
 Entrepreneurial Opportunities
 Conclusion

3.  Technology Introduction
 Three Main Categories
 Electrical KERS
 Mechanical KERS
 Hydraulic KERS
 Entrepreneurial Opportunities
 Conclusion

4.  Kinetic Energy Recovery System - Automotive system for recovering the
kinetic energy from waste heat generated during braking process
 Energy stored in reservoir - Flywheel, Battery, etc
 Utilized as auxiliary power during the accelerated process
 An energy storage device releasing energy to wheels when required

5.  Electrical KERS - use a motor-generator incorporated in the car’s
transmission which converts mechanical energy into electrical energy and
vice verse. Once the energy has been harnessed, it is stored in a battery
and released when required.
 Mechanical KERS - capture braking energy and use it to turn a small
flywheel which can spin at up to 80,000 rpm. When extra power is required,
the flywheel is connected to the car’s rear wheels. In contrast to an electrical
KERS, the mechanical energy does not change state and is therefore more
efficient.
 Hydraulic KERS - where braking energy is used to accumulate hydraulic
pressure which is then sent to the wheels when required.

6. Only 88.85 kJ required instead of 278.2,
68% energy saving.

7. No. Title Assignee priority date Type
EP 0016160 Vehicle braking and kinetic energy recovery system Purification Sciences Inc 20 July, 1978 compressed air
EP 0083557
Device for recovering the kinetic energy of a motor vehicle during braking and
exploiting same during speeding up
Ferrero S.p.A 6 January, 1982 electrical
US 4798053 Kinetic energy reclaiming system for vehicle Chang; Jimmy C.K. 10 December, 1986 compressed air
EP 0558662 Mechanical energy storage for vehicle parking brakes Allied-Signal Inc 30 November, 1990 flywheel
EP 0645272
Recovery system for dissipated energy of an engine motor vehicle during its
running conditions
Reis, Gianluigi 27 September, 1993 compressed air
US 6460332 Pressure oil energy recover/regeneration apparatus Komatsu Ltd 4 November, 1998 hydraulic
US 7293621
Vehicle drive system with energy recovery system and vehicle mounting
same
Charge-O-Matic Energy Recovery
Devices, Llc
10 April, 2002 electrical
EP 1433648 Energy recovery system for a work vehicle CNH Italia S.p.A 23 December, 2002 hydraulic
US 7315088 Fluid device for recovery of the kinetic energy of a vehicle Erriu Fernando 9 July, 2003 hydraulic
EP 1561625 Engine based kinetic energy recovery system for vehicles
International Truck Intellectual
Property Company, LLc
3 February, 2004 compressed air
US 7201095 Vehicle system to recapture kinetic energy Pneuvolt Inc 17 February, 2004 hydraulic
US 8290675
Recovery of energy in a hybrid vehicle having a hydraulic or pneumatic
braking system
Robert Bosch Gmbh 19 August, 2005 Electrical/hydraulic
EP 1764256 Energy regenerating device for recovering kinetic energy in motor vehicles Ippolito, Massimo 20 September, 2005 electrical
US 8327637 Hydraulic energy recovery system with dual-powered auxiliary hydraulics Parker-Hannifin Corporation 28 March, 2006 hydraulic
EP 2125413 Hybrid vehicle energy management methods and apparatus Mack Trucks, Inc. 22 February, 2007 electrical
US 8111036
System for electrically connecting and disconnecting a vehicle generator from
a vehicle storage unit
Stephen George Rosenstock 26 February, 2007 electrical
US 20110320074 Kinetic energy recovery and electric drive for vehicles Erlston Lester J, Miles Michael D 19 December, 2007 electrical
EP 2282907 An energy recovery system for a vehicle driveline Torotrak (Development) Limited 20 May, 2008 flywheel
US 8281587 Supercharged boost-assist engine brake
International Engine Intellectual
Property Company, Llc
13 August, 2009 supercapacitor
EP 2492125
Method for recovering kinetic energy of hybrid electric vehicles, and energy
accumulator using compressed air
Instituto Alberto Luiz De Coimbra 15 October, 2009 hydraulic
US 20120212042 Hydraulic assembly and brake system for a motor vehicle Robert Bosch Gmbh 2 November, 2009 hydraulic
US 8172022
Energy recovery systems for vehicles and vehicle wheels comprising the
same
Toyota Motor Engineering &
Manufacturing North America, Inc
30 November, 2009 flywheel
EP 2397358 Regenerative brake system for a vehicle Paccar Inc 21 June, 2010 electrical/mechanical
US 20120080249 Front wheel energy recovery system Yates Iii William MIngram Benjamin T 4 October, 2010 hydraulic
EP 2450246 Energy recovering device for recovering energy in a vehicle ZanettiStudios S.r.l 3 November, 2010 electrical
US 8344529 Method and system for energy harvesting Energy Intelligence, LLC 18 January, 2011 electrical/mechanical

8.  Comparison of energy storage used in vehicles
Source: Energy Storage Systems Cost Update, Sandia National Laboratories (SAND2011-2730)
April 2011
Electrical Hydraulic Mechanical

9.  Technology Introduction
 Three Main Categories
 Electrical KERS
 Mechanical KERS
 Hydraulic KERS
 Entrepreneurial Opportunities
 Conclusion

10.  Technology: Energy Conversion
 The vehicle’s electric traction motor is operated as a generator during braking
and its output is supplied to an electrical load.
 Examples: Electrical Pancake Generator in cars
Source:
(1) Cibulka, J., “Kinetic energy recovery system by means of flywheel energy storage”, Advanced Engineering
3(2009)1, ISSN 1846-5900
(2) Lester J Erlston, Michael D. Mikes, “ Kinetic energy recovery and electric drive for vehicles”, US Patent
Application Publication, US 2011/03200074, Dec 29,2011

11.  The Development Direction
 High energy density: to store energy efficiently
 High power density: to release the energy quickly
 However, sometimes the development path (indicated by the arrows) is NOT
straight forward to the target.
Source: Electric Power Research Institute, “Electricity Energy Storage Technology
Options: A White Paper Primer on Applications, Costs, and Benefits”, 2010
Lead Acid Battery
Supercapacitor
Compressed Air
Energy Storage
Superconducting Magnetic
Energy Storage
Flow Battery

12.  Application of Supercapacitors in Vehicles
 Supercapacitor is one of the six key enabling technologies for electric
vehicles.
 Supercapacitor manufacturers are active and many others are tending on
targeting electric vehicle sector.
Source: Dr Peter Harrop, “EV lessons from Energy Harvesting and Supercapacitors event”,
IDTechEx, 15 Nov 2012

13.  Start a car with Supercapacitors
Source: CAP-XX, “Supercapacitors for Automotive & other vehicle application”, March
2012

14.  Case Study -1
Source: CAP-XX, “Supercapacitors for Automotive & other vehicle application”, March
2012

15.  Comparison with Batteries & Conventional Capacitors
Source: P Kurzweil, “Electrochemical Double-Layer Capacitors” Encyclopedia of
Electrochemical Power Sources, Pages 607-633, 2009

16.  Cost Comparison between Battery & Supercapacitor
 Cost per energy ($/kWh) of supercapacitor is almost 10 times of battery.
 Cost per power ($/kW) of supercapacitor is only ~25% of battery.
Source: Andrew Burke, “Ultracapacitor Technologies and Application in Hybrid and
Electric Vehicles”, International Journal of Energy Research, July 2009

17.  Specific properties of different supercapacitor technologies
Source: P Kurzweil, “Electrochemical Double-Layer Capacitors” Encyclopedia of
Electrochemical Power Sources, Pages 607-633, 2009

18.  Carbonaceous materials for supercapacitors
Source: P Kurzweil, “Electrochemical Double-Layer Capacitors: Carbon Materials”
Encyclopedia of Electrochemical Power Sources, Pages 607-633, 2009

19.  The energy density of supercapacitors are improved through using
different materials as electrode.
Source: Charith Tammineedi, “Modeling Battery-ultracapacitor Hybrid Systems For Solar
And Wind Applications”, A Thesis in Energy and Mineral Engineering , The Pennsylvania
State University, 2011

20.  The lifecycle degradation is improved by using Carbon NanoTubes as
electrodes in superacapacitors.
supercapacitor
with CNT
Other kinds of
supercapacitor
Source: Malachi Noked, Sivan Okashy, Dr. Tomer Zimrin, Prof. Doron Aurbach,
“Composite Carbon Nanotube/Carbon Electrodes for Electrical Double-Layer Super
Capacitors”, Angewandte Chemie, Volume 124, Issue 7, pages 1600–1603, February
13, 2012

21.  Both energy and power density are improved by using Graphene:
 Energy density - 25 Wh/Kg (comparable with conventional batteries)
 Power density - 10 KW/Kg (suitable for surge power delivery)
Source:
(1) Yan Wang, etc, “Super Capacitor Devices Based on Graphene Materials” , J.
Phys. Chem. C, 2009, 113 (30), pp 13103–13107, ACS, 2009
(2) Hongcai Gao, etc, “High-Performance Asymmetric supercapacitor based on
Graphene Hydrogel and Nanostrucutred MnO2“ ACS, 2012
supercapacitor
with GH//MnO2
Other kinds of
supercapacitors

22.  Technology Introduction
 Three Main Categories
 Electrical KERS
 Mechanical KERS
 Hydraulic KERS
 Entrepreneurial Opportunities
 Conclusion

23.  Mechanical KERS, i.e., Flywheel KERS (Flybrid ®)
 More efficient & less power loss in energy transfer
 Direct translational kinetic energy to rotational kinetic energy transition
 Flybrid® grows rapidly in racing cars having potential in commercial cars
 Market players like Volvo, Jaguar, Ford have been actively in Flybrid®

24.  Rotational engergy:
 where
 Another equation – energy density:
 Material and size significantly change stored energy
 Flywheel now can spin as high as 60,000RPM
 400kJ usable energy storage for 60kW power transmission
 Carbon fiber (25kg weight, 13L volume, A4 Paper Size)
 Constraints: material tensile strength, weight, space
Year Material Weight Ultimate Strength
1940s Steel 1633kg Up to 900Mpa
1950s Titanium alloy ~800kg Up to 1100Mpa
2000s Carbon Fiber 25kg 1600 – 6400Mpa
Future Carbon Nanotube <20kg 11000 – 63000Mpa

25.  Proportion of Kinetic Energy recoverable under braking values in Joules
Douglas. C & Chris. B, Mechanical Hybrid comprising a flywheel and CVT for Motosport & mainstream
Automotive applications, 2008
62.7%

26.  Proportion of stored energy released back to the wheels values in
Joules
Douglas. C & Chris. B, Mechanical Hybrid comprising a flywheel and CVT for Motosport & mainstream
Automotive applications, 2008
83.9%

27. Carbon-fiber-
reinforced
polymer
Glass-fiber-
reinforced
polymer
Alloy

28. 0
1000
2000
3000
4000
5000
6000
7000
1940 1950 1960 1970 1980 1990 2000 2010
Tensile Strength of
Material (MPa)
Steel
Titanium
E-Glass
Laminate
Carbon Fiber
Carbon Fiber
Carbon Fiber
Toray T1000G
S2-Glass
Future:
Carbon Nanotube: 63000
Graphene:130000

29. 0
1
2
3
4
5
6
7
8
9
1940 1950 1960 1970 1980 1990 2000 2010
Material's Density
(g/cm3)
Steel
Titanium
E-Glass
Laminate
Carbon Fiber
Carbon Fiber
Carbon Fiber
Toray T1000G
S2-Glass
Future:
Carbon Nanotube: 0.37-1.34
Graphene:1.00

30. 0
500
1000
1500
2000
2500
3000
3500
4000
1940 1950 1960 1970 1980 1990 2000 2010
Specific Energy
Specific Energy
(kJ/Kg)
Steel
Titanium
E-Glass
S2-Glass
Laminate
Carbon Fiber
Carbon Fiber
Carbon Fiber
Toray T1000G

31. 0
20000
40000
60000
80000
100000
120000
140000
Specific Energy
Specific Energy
Graphene
Carbon Nanotube
Carbon Fiber
Toray T1000G
(kJ/Kg)

33.  Advantages
 High Efficiency
 Low weight
 Long lifespan
 Wide working
temperature range
 Low impact to
environment
 Disadvantages
 Space & size constraints
 Maintenance
 Safety

34.  Materials
 Newer materials: carbon nanotube, etc
 Process & Design
 More efficient in transmission
 Gears design
 Future
 Opportunity of magnetic rotor
 Multi-flywheel
 Aircraft application

35.  Technology Introduction
 Three Main Categories
 Electrical KERS
 Mechanical KERS
 Hydraulic KERS
 Entrepreneurial Opportunities
 Conclusion

36.  Axial Piston Unit + Gearbox (pump)
 Hydraulic Pressure Accumulator
 Pressure Relief Valve
 Valve Control Block HIC
 Electronic Controller RC

37. Initial Status
BrakingAccelerating

41. http://www.grainger.com/Grainger/hydraulic-accumulator/hydraulic-system-
components/hydraulics/ecatalog/N-c7a
12312.5
6512.5
3568.75
2762.5
1850
$1,000
$10,000
$100,000
0 0.05 0.1 0.15 0.2
DollarperGal
Size (Gal)
Price per unit volumn
Hydraulic Accumulator

42.  Hydraulic Hybrid Vehicles
 Conceptual/Passenger car – minor
 McLaren Mercedes used it on 1999
 City Bus/Delivery Trucks/Garbage Trucks
 EATON-UPS HLA project: up to 35% improved fuel economy
and up to 30% CO2 emissions reduction
 Bosch Rexroth HRB for garbage trucks in Germany and US, 20-25% fuel save
and 2-3 times brake life extended.
- http://www.gizmag.com/formula-one-kers/11324/
- http://www.marketwatch.com/story/ups-to-add-40-hydraulic-hybrid-vehicles-to-its-fleet-2012-10-03

43.  Advantages
 High energy conversion
efficiency
 Disadvantages
 Size
 Weight
 Safety

44.  Apply to heavy vehicles
 Size & weight reduction
 Large Diameter Flat Format (LDFF) hydraulic motors
 Development of Piezoelectric Hydraulic Pump

45.  Technology Introduction
 Three Main Categories
 Electrical KERS
 Mechanical KERS
 Hydraulic KERS
 Entrepreneurial Opportunities
 Conclusion

46.  KERS is a effective way to improve fuel efficiency by recovering
the kinetic energy from braking energy
 Economically save the cost especially the fuel price is rising.
 Environmentally, reduced waste exhaust gas that cause pollution
 Currently, mostly widely adopted in the Formula 1 racing
 Commercial cars launched such as Mercedes S-Series Hybrid.
 http://www.youtube.com/watch?v=TgVvzoxGj_g
 Battery? Flywheel? Hydraulic?
 Future application in Aviation & Sailing

47.  Technology Introduction
 Three Main Categories
 Electrical KERS
 Mechanical KERS
 Hydraulic KERS
 Entrepreneurial Opportunities
 Conclusion

48.  Comparison of three technologies of KERS
 KERS, with whatever technology, is still in the stage of explore and
research, such as F1 and Le Mans, where commercialization of KERS still
has a long way to go.
Technologies Scale Material Cost ($/kW)
Electrical -
supercapacitor
Larger Graphene 3626-10000
Mechanical - flywheel
Smaller (weight &
space constraints)
Steel, Titanium,
carbon fiber,
carbon nanotube
1950-2200
Hydraulic Larger steel, carbon fiber 2500-4300