PHEVs Component Requirements and Effi i iEfficiencies

d d hi l h l i2009 DOE Hydrogen Program and Vehicle Technologies Annual Merit Review 

May 19, 2009

Phil Sharer, Aymeric RousseauArgonne National Laboratory

Sponsored by Lee Slezak

This presentation does not contain any proprietary, confidential, or otherwise restricted information

Project OverviewTimeline

Start – July 2008

d b

Barriers

Set targets for the different technical teams End – September 2009

75% Complete

technical teams

Perform cost benefit analysis

Budget

DOE

FY08 $ 200k

Partners

U.S. EPA

ANL B ’ FY08 $ 200k

FY09 $ 400k ANL Battery’s group 

2

Main Objectives

Define targets for the different technical teams.

How does each assumption influence the component o does eac assu pt o ue ce t e co po e trequirements?

Can we lower a component requirement without significant fuel l ?economy loss?

What are the most appropriate battery energy/power to maximize fuel displacement?maximize fuel displacement?

What is the best control strategy philosophy for different battery characteristics?

What should the cost targets be to have specific payback?

3

Milestones

Q1 Q2 Q3

Implement RWDC

Q4

Implement RWDC

Define Assumptions(performance, cost)

Define Vehicles

Develop Analysis Methodology

Define Vehicles

Run Simulations

Perform Cost Benefit

Analyze Fuel Efficiency

Run Simulations

Perform Cost Benefit

Write report

Current Status

4

Current Status

Approach

Real World Drive Cycles

AutomatedSizing

Analysis(Distribution)

10

15

20

25

Spee

d (m

ph)

Drive cycle

10

15

20

25

Spee

d (m

ph)

Drive cycle

Motor Power for Cycle

Vehicle Assumptions

6

8

10

ence

s (%

)

60

70

80

90

100

wer

(%)

Mean=115kW

Median=100kW

Std=48kW

Distribution of Pess max discharging for each trip

6

8

10

ence

s (%

)

60

70

80

90

100

wer

(%)

Mean=115kW

Median=100kW

Std=48kW

Distribution of Pess max discharging for each trip

0 200 400 600 800 1000 12000

5

10

Time (s)

S

0 200 400 600 800 1000 12000

5

10

Time (s)

S

0

5

10

15

20

25

30

35

40

Spee

d (m

ph)

Drive cycle

0

5

10

15

20

25

30

35

40

Spee

d (m

ph)

Drive cycle

30

35Drive cycle

30

35Drive cycle

Battery Power

Engine Power0

2

4

Num

ber o

f occ

ure

0 50 100 150 200 250 3000

10

20

30

40

50

Cum

ulat

ive

pow

Pess (kW)

Std 48kW

Number of trips=111

0

2

4

Num

ber o

f occ

ure

0 50 100 150 200 250 3000

10

20

30

40

50

Cum

ulat

ive

pow

Pess (kW)

Std 48kW

Number of trips=111

12

16

20

f occ

uren

ces

(%)

50

60

70

80

90

100

tive

pow

er (%

)

Mean=-32kW

Std=12

Number of cycles=290

Distribution of Pess max charging for each cycle

12

16

20

f occ

uren

ces

(%)

50

60

70

80

90

100

tive

pow

er (%

)

Mean=-32kW

Std=12

Number of cycles=290

Distribution of Pess max charging for each cycle

0 500 1000 1500 2000 2500 30000Time (s)

0 500 1000 1500 2000 2500 30000Time (s)

0 500 1000 1500 2000 25000

5

10

15

20

25

Time (s)

Spee

d (m

ph)

0 500 1000 1500 2000 25000

5

10

15

20

25

Time (s)

Spee

d (m

ph)

Battery Energy

ConvergenceNo 6

8

10

ccur

ence

s (%

)

50

60

70

80

90

100

e po

wer

(%)

Mean=123kW

Median=107kW

Std=54kW

Number of trips=111

Distribution of Pess sized for each trip

6

8

10

ccur

ence

s (%

)

50

60

70

80

90

100

e po

wer

(%)

Mean=123kW

Median=107kW

Std=54kW

Number of trips=111

Distribution of Pess sized for each trip

0

4

8

Num

ber o

-90 -80 -70 -60 -50 -40 -30 -20 -10 00

10

20

30

40

cum

ula

Pess (kW)0

4

8

Num

ber o

-90 -80 -70 -60 -50 -40 -30 -20 -10 00

10

20

30

40

cum

ula

Pess (kW)

>110 TripsOne day in Kansas City

Yes

Midsize Vehicle0

2

4

Num

ber o

f o

0 50 100 150 200 250 3000

10

20

30

40

Cum

ulat

iv

Pess (kW)

p

0

2

4

Num

ber o

f o

0 50 100 150 200 250 3000

10

20

30

40

Cum

ulat

iv

Pess (kW)

p

5Only Hot Conditions Assumed, no Grade!

Battery Power and Usable Energy R i F i f V hi l MRequirement as a Function of Vehicle Mass

6

Engine Power Requirements Provided to h E i T h T the Engine Tech. Team

Engine Power per vehicle configuration

Engine Power per vehicle classes

7

Different PHEV Powertrains and Battery Sizes

Powertrain Configuration

BatteryEnergy

PHEVClass

4 kWh

Configuration gy

4 kWh

8 kWh

Low Energy PHEVPower Split PHEV

12 kWh12 kWh

16 kWh

High Energy PHEVSeries PHEV

8

Kernel Density Used to Compare Options

48

Distribution Fuel Consumption Conventional Vehicle

histogram

l

36

s (%

)

Mean Value

24f occ

uren

ces

Num

ber o

f

12

9

5 5.5 6 6.5 7 7.5 80

Fuel consumption (liter/100km)

One Control per Configuration was Selected Based on a Fuel Economy and Number of Engine Starts -y gCriteria

140Mean Values

PHEV 12 kWh Series Thermostat ControlPHEV 16 kWh Series Thermostat Control

100

120

n [W

h/km

]

PHEV 8kWh Split Optimum Engine Power

∆2

60

80

nsum

ptio

n p p g

PHEV 4kWh Split LoadEngPwr 10miCD

∆Fuel Consumption per added kWh Non Linear

20

40

ectri

cal C

on PHEV 4kWh Split LoadEngPwr 10miCD∆1

0 1 2 3 4 5 6 7-20

0

Ele ConventionalSplit HEVLinear relation between 

Electrical and Fuel Consumption

10

0 1 2 3 4 5 6 720

Fuel Consumption [l/100km] Preliminary results

Fuel Consumption Lowers with Increasing Battery EnergyBattery Energy

1.5Conventional(mean = 6.53 l/100km, std = 0.30)HEV Split

1

(mean = 4.85 l/100km, std = 0.46)PHEV 4kWh Split(mean = 3.31 l/100km, std = 0.77)PHEV 8kWh Split(mean = 2.36 l/100km, std = 0.89)PHEV 12 kWh Series1

ensi

ty [-

]

PHEV 12 kWh Series(mean = 0.91 l/100km, std = 0.82)PHEV 16 kWh Series(mean = 0.67 l/100km, std = 0.67)

0.5

De

11

0 1 2 3 4 5 6 7 80

Fuel Consumption [liter/100km] Preliminary results

Battery Usage Linked to Usable Energy -> Diff t I t Lif f Diff t E i

0.025 PHEV 4kWh Split(mean = 52.43 Wh/km, std = 28.88)PHEV 8kWh Split(mean = 91 74 Wh/km std = 35 16)

Different Impact on Life for Different EnergiesMost cycles use low 

0.02

(mean = 91.74 Wh/km, std = 35.16)PHEV 12 kWh Series(mean = 128.45 Wh/km, std = 20.14)PHEV 16 kWh Series(mean = 138.32 Wh/km, std = 17.38)

These configurations offer

energy consumption

Most cycles use high energy 

0.015

nsity

[-]

These configurations offer range of battery energy 

usage

consumption

0.01

Den

0.005

0 20 40 60 80 100 120 140 160 180 2000

Electrical Energy Consumption [Wh/km]

12

Preliminary results

4kWh Battery Energy Provides 50% of the Gains Achieved with 16 kWh Battery

10Conventional

7

8

9

ters

]

ConventionalHEV SplitPHEV 4kWh SplitPHEV 8kWh SplitPHEV 12 kWh Series

4

5

6

el c

onsu

med

[lit PHEV 16 kWh Series

60

80

100

ng [%

]

1

2

3Fue

0 5 10 15 200

20

40

Battery Size [kWh]

Fuel

Sav

i

0 10 20 30 40 50 60 70 80 900

Distance [miles]

13

Battery Size [kWh]

Preliminary results

Used Battery Energy as a Function of Driving Distance

10

12ConventionalHEV SplitPHEV 4kWh Split PHEV 8kWh Split

8

ed [k

Wh]

PHEV 8kWh SplitPHEV 12 kWh SeriesPHEV 16 kWh Series

Same control for series independently of 

gy [k

Wh]

4

6

nerg

y co

nsum

e

battery energies

For medium distance, we see largest energy consumption diff d t d i i h t i titte

ry E

nerg

2

Ele

ctric

al e

n difference due to driving characteristics

For short distance, we have similar electrical consumption > Linked to low power demand?

Use

d B

at

2

0

consumption ‐> Linked to low power demand?

0 10 20 30 40 50 60 70 80 90-2

Distance [miles]

14

Preliminary results

Constant Payback Period Requires Longer Dri ing Distances for Bigger Batter PacksDriving Distances for Bigger Battery Packs Equation for break even lines with conventional vehicle:

15Series 12kWh ThermoSeries 16kWh Thermo

10

[yea

rs]

Series 16kWh ThermoSplit 4kWh MinEngPwrSplit 8kWh MinEngPwr

The further you drive,

5Pay

back

[ The further you drive, the better the payback

0 20 40 60 800

Celec = 0.07 $/kWh

Cfuel = 3$/gallon

15

0 20 40 60 80Daily Distance [miles] Preliminary results

Fuel Price Significantly Influences Payback P i dPeriod

Spikes due to small ] pnumber of data points for long 

distances

back

[yea

rs]

Celec = 0.07 $/kWh

Cbattery = 4128 $

Pay

b

Benefit of 1$ i li (1000$/kWh)

Cbase = 30791 $

increase non‐linear

16

Preliminary results

Future Activities

■ Update the cost assumptions based on litterature search and expert discussions (D Santini & A Vyas)discussions (D. Santini & A. Vyas).

■ Complete fuel efficiency and cost analysis

■ Add HEV vehicle

P f b fi l i b d l i d fi h■ Perform cost benefit analysis based on several scenarios to define the most approriate vehicle for different options (i.e., battery energy, battery cost, distance, fuel cost...).

Wh t i th i t f i th hi l b h d d i th d ?■ What is the impact of assuming the vehicle can be charged during the day?

■ How does the results based on the RDWC compare with the latest J1711 Procedure (using both National and RWDC Utility Factors).

■ Perform MonteCarlo analysis on the control strategy parameters to provide an uncertainty value.

17

Summary■ Impact of RWDC on Fuel Efficiency

– Several vehicles with different powertrain configurations and battery energies were simulated.

– A single control strategy was selected for each option based on a combination of fuel efficiency and engine ON/OFF criteria.

– The fuel efficiency was compared with a conventional vehicle to assess the y ppotential fuel displacement over the Kansas City RWDC.

■ Impact of RWDC on Cost Benefit Analysis

– With current pricing, long payback period due to high battery cost

– Increasing fuel price significantly influences payback period and is a major factor for the rentability of a PHEV

– Benefits of price reduction on payback nonlinear

– You should regularly drive longer than what your AER theoritically allows

18

References G. Singh, S. Hagspiel, M. Fellah, A. Rousseau, “Impact of RWDC on PHEVs fuel 

efficiency and cost for different powertrain and battery characteristics”, EVS 24, Norway, May 2009

A. Rousseau, “Impact of Real‐World Drive Cycles on PHEV Battery Requirements”, SAE 2009‐01‐1383, World Congress, April 2009 

A. Rousseau, S. Pagerit, M. Fellah, “PHEV Battery Requirements Uncertainty g y q yBased on Real World Drive Cycles”, EDTA, Dec 2008, DC

A. Rousseau, N., Shidore, R., Carlson, D., Karbowski,  “Impact of Battery Characteristics on PHEV Fuel Economy”, AABC 2008, Tampa (May 2008)

J. Kwon, J. Kim, E. Fallas, S. Pagerit, and A. Rousseau , “Impact of Drive Cycles on PHEV Component Requirements”, SAE paper 2008‐01‐1337, SAE World Congress, Detroit (April 2008). 

A. Rousseau, N. Shidore, R. Carlson, V. Freyermuth, “Research on PHEV Battery Requirements and Evaluation of Early Prototypes, AABC 2007, Long Beach (May 16‐18)

19