BEVs for ICEV drivers The development of requirements for Battery Electric Vehicles (BEVs) to satisfy current driving behaviours in premium internal combustion engine vehicles (ICEVs) Tim Holton Advanced Propulsion Group, Jaguar Land Rover
What kind of BEV would an ICEV driver buy?
1. Understanding the customer Systems engineering perspectives
2. ICEV data source Jaguar Land Rover lease fleet data
3. Driving distances (BEV range) Trip chains & driver adjustments
4. Parking times (BEV refuelling) Intervening parks
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1. Understanding the customer i. Background research
Source: Mckinsey 2017
Roughly 90 percent of the personal vehicles on the road daily could be replaced by a low-cost electric vehicle available on the market today, even if the cars can only charge overnight
Whilst 87% travelled under 40 miles/day, the desired average minimum range of a BEV was 215 miles. 3
1. Understanding the customer iii. Vehicle requirements are derived from customer requirements
Customer Needs
Vehicle
Systems & Components
Functional Validation
Requirements Definition
Conceptual Design
Detailed Design
Vehicle Testing
Component Testing
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1. Understanding the customer iii. Vehicle requirements are derived from customer requirements
Customer Needs
Vehicle
Systems & Components
Travelling Behaviour
Driving distance
Parking locations
Range capability (miles)
Parking duration
Refuelling time (minutes)
Battery size (kWh) Battery C-rate
Charging power(kW)
Willingness to adapt
Refuelling energy (miles)
Interoperability
Vehicle efficiency (wh/mile) 5
2. ICEV data source InControl data from Jaguar Land Rover lease vehicles ‘InControl’ sample dataset for existing drivers:–
800 vehicles, 450000 trips
–
Total distance: 6.4 million miles
–
Total duration: 360 vehicle years
–
Mean daily distance: 48 miles −
(range of 20 to 50 miles quoted in the literature)
How can we use this data to derive BEV requirements? 6
3. Driving distances and BEV range i. Trip Chains A ‘trip chain’ is a sequence of trips bounded by a ‘terminus park’.
The terminus park may be defined by:•
an ‘anchor’ location (‘Home’, ‘Work’ , ‘Anywhere’) and/or
•
a ‘threshold’ park duration (e.g. ‘Overnight’ or ‘>8 hours’)
Home
Shop
Terminus parks represent routine charging events Trip chain Terminus park
School
Terminus park Intervening parks
Intervening parks represent opportunity charging events Work
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3. Driving distances and BEV range i. Trip chains applied to a 25000 mile p.a. driver with 37 mile commute
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3. Driving distances and BEV range i. Trip chains applied to a 25000 mile p.a. driver with 37 mile commute >1hr terminus park
Trip chain >8hr terminus park Driver 1 - 240 mile usable range BEV Trip chain
- satisfies ~90% of home overnight trip chains - ‘adjustments’ for the remaining 10%
More convenient routine charging leads to longer trip chains
Overnight at home
Overnight away from home
Overnight at home
Trip chain 9
3. Driving distances and BEV range i. Trip chains applied to two 25000 mile p.a. drivers with 37 mile commute
Driver 1
Driver 2
- 240 mile usable range BEV
- 120 mile usable range BEV
- satisfies ~90% of home overnight trip chains
- satisfies ~90% of home overnight trip chains
- ‘adjustments’ for the remaining 10%
- ‘adjustments’ for the remaining 10%
BEV suitability depends on occasional usage, not average usage
How do we avoid, or help with, the ‘adjustments’ in red? 10
3. Driving distances and BEV range i. Trip chains applied to two 25000 mile p.a. drivers with 37 mile commute
Daily travel distances were only weakly related to lower range satisfaction (not significant)…The regularity/predictability of users' mobility patterns, the percentage of journeys not coverable because of range issues, and users’ individual comfortable range accounted for variance in range satisfaction.
Is it possible to relate ‘Driving distance’ and ‘% Adjustments’ to a population of users? 11
3. Driving distances and BEV range ii. Driver adjustments
Adjustments Ideal Journey and Parking behaviour
Ability to swap transport
Flexible Travel plans
Willingness to charge en route
Real World Range Target Real World Charge Rate
‘Adjustment’ is what allows a current ICE driver to accommodate BEV limitations
Premium customers will always desire to minimise the level of adjustment required 12
Usable BEV Range
Number of days/year customer will ‘Adjust’
‘n’ customers driving distance data
% Customers accepting BEV
3. Driving distances and BEV range iii. Relating Driving distance and Adjustments to a population
24 days public charge
Premium customers 6 day public charge
Usable BEV Range
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BMW i3 Nissan Leaf
Tesla
3. Driving distances and BEV range iii. Relating Driving distance and Adjustments to a population
Median = 6 Median = 40 Median = 15
Comparison of ICE trip chain analysis and Tesla real world behaviour Real world Tesla data shows a similar trend to the ICEV trip chain analysis. Tesla drivers are using superchargers more often than trip chain analysis predicts. This could be for a number of reasons:1. US based sample rather than UK 2. Free supercharger use incentivising opportunity charging events 3. Sample size 4. Early adopters may have more acceptance of public charging 5. Vehicle not being fully charged overnight
200 miles usable range Median adjustments = 15
Tesla Model S ~200 miles usable range Median adjustments = 25
Supercharger events per year
4. BEV Adaption – Refuelling (Opportunity charging) i. Trip chain Intervening parks charging requirements Trip chain
Terminus park
Trip 1 > 90 mins
Trip 2 Terminus park
Stop < 1 hour
Required range increase during intervening park: 10 miles/min charging would mean:
Distance of Trip 2 (miles) Stop time (min)
•
73% of stop times are long enough to charge for Trip 2
20 miles/min charging would mean: •
92% of stop times are long enough to charge for Trip 2
The Freedom of motoring
“…the car has been such a success over the past century thanks to its unparalleled flexibility. Having the freedom to go where you like, when you like and with a minimum of inconvenience is something the public simply don’t want to give up.”
Neil Winn, Autocar
THANK YOU
Tim Holton Electrification IDL, Warwick University CV4 7AL
Jaguar Land Rover W/1/26 Abbey Road, Whitley Coventry CV3 4LF, UK jaguarlandrover.com
M +44(0)7881 234 105
[email protected]
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