The document discusses the value of weight reduction for plug-in electric vehicles (PEVs) and plug-in hybrid electric vehicles (PHEVs). It finds that with the limited energy storage in these vehicles, low vehicle mass through designs using aluminum are emphasized to reduce energy consumption and increase range. Specifically, a 10% reduction in vehicle mass can result in a 10% increase in vehicle range and a 4-6% reduction in required battery size. Regenerative braking is also important for recovering energy in low mass vehicles, recouping 66-69% of energy lost to rolling resistance in city driving. Lighter aluminum structures can reduce overall energy requirements by 1.2-3.4 kWh, lowering costs given current

1. Value of Weight Reduction to
PEV/PHEVs
Opportunities with Aluminum
Michael Bull
Novelis
on behalf of
The Aluminum Association’s
Aluminum Transportation Group (ATG)
Fred Jacquelin RICARDO
1

2. Defining Who We Are
The Aluminum Association’s Aluminum Transportation Group (ATG)
www.aluminumintransportation.org 2

3. Key Topics
• Range vs. Weight and Cost (vehicle & battery)
• Business Trade-offs:
- Structure cost & weight vs. Battery cost & weight
• Regenerative Braking vs. Vehicle mass
- More or less weight sensitive?
3

4. Assumptions
• Li –Ion battery:
- 115 Wh/kg (51-209 kg)
- 155 Wh/l
- SOC 0.9-0.25
- $750 kWh
• Small Vehicle based on BMW Mini:
- Tradition Design =781 kg
- Lightweight Design = 627kg (154 kg savings or 19.7%)
- 40 and 80 mile range
4

5. Mass Breakout (Traditional)
Small EV Steel (781kg)
38, 5%
58, 7%
BIW
0, 0%
closures
183.5, 25%
34, 4% body other
23, 3% chassis
interior
71.5, 9% electrical
132.7, 17%
assembly
Gas PHEV
65.5, 8%
Battery
174.4, 22%
Motor & Controller
5

6. Mass Breakout (Lightweight)
Small EV Aluminium (627kg)
37, 6%
51.0, 8% BIW
91.8, 15% closures
0.0, 0%
body other
34.0, 5%
44.2, 7% chassis
23.0, 4%
interior
62.1, 10% electrical
assembly
132.7, 21%
Gas PHEV
Battery
151.4, 24%
Motor & Controller
6

7. Energy Balance
Small Car Energy Balance (40 mile)
4.00
2.00
0.00 Regen Gain
1 2 3 4 Brake Loss
-2.00 Differential Loss
Motor/Gen Loss
kWh
-4.00
Converter Loss
-6.00 Battery Loss
Rolling Loss
-8.00 Aero Loss
-10.00
-12.00
Case Study #
Case Case Case Case Case Case Case Case
1 2 3 4 1 2 3 4
FTP FTP
% kWh
Aero 22.3 24.8 29.4 32.7 1.97 1.97 1.97 1.93
rolling 30.2 28.9 26.2 23.6 2.67 2.29 1.75 1.40
battery 4.1 4.1 4 3.8 0.36 0.33 0.27 0.22
converter 7.6 7.5 7.2 6.8 0.67 0.59 0.48 0.40
motor/generator 33.2 32.2 30.8 30.8 2.93 2.55 2.06 1.82
differential 2.5 2.4 2.3 2.2 0.22 0.19 0.15 0.13
brake 0.1 0.1 0.1 0.1 0.01 0.01 0.01 0.01
regen 20.9 20 18.1 15.6 1.85 1.59 1.21 0.92
7

8. EV Mass vs..
Energy Consumption
1.3 KWh/100 Mi per 100 Kg

9. Regen Braking – Small Car

10. Summary
• PEV or PHEV, with so little stored energy, places emphasis on low mass
design (and low aero losses).
• Consumption ranged 0.146 kWh/mi (600 Kg) to
0.302 kWh/mi (1800 Kg). Or 1.5-3 kg of battery/mile travelled.
• 10% mass reduction approximates to 10% increase in range and 4-
6% reduction in battery size.
• Regenerative braking is equally important to low mass vehicles. (66-
69% recovery of rolling in city, 2-5% in highway drive cycle).
• Lighter mass structures reduced energy requirements from 1.2 – 3.4
kWh, about 10%, which can significantly reduce vehicle costs at current
Lithium-ion battery costs.

11. Thank you
Visit us at:
www.aluminumintransportation.org