gcorelab thermal solution for electric vehicle
DESCRIPTION
Liquid Cooling for Electric Vehicle/ Hybrid Electric Vehicle Battery: A Case StudyTRANSCRIPT
Lithium ion battery
AdvantagesImpressive energy densityGood power densityGood charge/discharge efficiencyLong lifespanNo environmental issues
However, lithium ion battery is sensitive to temperature and could be a risk to fire safety.
The dominant EV battery
High temperatures can be a result of:1.Ambient temperature2.Fast charging3.Drawing large amount of energy from batteries
Lithium ion batteryTemperature problems
Low temperatures can be a result of:Ambient temperature
Temperature gradients can be caused by:Uneven cooling/heating of batteries
Lithium ion batteryTemperature problems
Batteries make up about 70% of the cost of an electric vehicle
Good thermal management can enable longer lifespan, lower costs and improve safety for EV batteries
Thermal ManagementCritical for EV batteries
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No CoolingAir Cooling
Low resistance cells
GCoreLab’s Liquid CoolingGCoreLab’s Liquid Cooling
Source: NREL – Battery Thermal Modeling and Testing
Relative Capacity of Battery vs. Time
GCoreLab’s Liquid Cooling
Battery capacity of 80% for more than 9years
Increased lifespan of 2years compared to Air Cooling
Thermal ManagementCritical for EV batteries
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Chevrolet Volt Ford Focus
Smart fortwo ED Tesla Roadster
Liquid Cooling TechnologyCurrent Users
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Requirements of the thermal system:
1. Temperature (15-40°C)
2. Small temperature range within different battery cells
3. Insulation between battery cells
4. No leakage
5. Light weight (<200kg)
6. Low cost (5-10% of battery cost)
Case StudyThermal Management for Electric Bus
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GCoreLab’s Approach1. Temperature (15-40°C)
- Easily achieved with low flow rates for our liquid cooling/heating system
- Possibility of routing fluid flow to heat sources or cooler regions in vehicle
2. Small temperature range within different battery cells
- Supply of flow to liquid cold plates in a parallel configuration
- Uniform cooling of individual cells
3. Insulation between battery cells
- Insulative thermal interface material
- Overmolding of high thermal conductivity plastics
- Liquid cold plates made out of high thermal conductivity plastics
Case StudyThermal Management for Electric Bus
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GCoreLab’s Approach4. No leakage
- Vacuum brazing
- Liquid cold plate under battery packs
- Pipe connections outside battery box
5. Light weight
- Liquid cold plates made out of aluminium or high thermal conductivity plastics
- Sharing of liquid cold plates amongst individual cells instead of dedicated plates
- Smaller pumps due to lower pressure drops across plates
6. Low cost
- Lower maintenance cost due to smaller pump and lower pressures involved
- Usage of plastic materials instead of the more costly metals
Case StudyThermal Management for Electric Bus
Jacket of minichannels using oblique fins around the battery pack
Thin profile to slot between gaps of the individual cells
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Incorporation in Battery PacksGCoreLab Thermal Solution
Combined system to cool multiple heat generating devices such as motor controllers, ultra-capacitors and motors
Better performance in components
More compact
Lower cost
less equipment
Less weight
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Incorporation in AutomobileGCoreLab Thermal Solution
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Conclusion
High performance thermal management• Higher efficiency, recoverable power and capacity
• Longer battery life/better reliability
• Allows fast charging
• Prevents thermal runaway
• Compact system
Customizable thermal management to incorporate with existing battery packs and components
Thank you!