Integrated EV Thermal Loop Using Ambient Air and Waste Heat
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electric vehicles face performance degradation in cold weather due to battery temperature issues and inefficient heating systems, which rely on complex refrigerant networks and low-grade heat sources, leading to reduced heating efficiency and increased complexity.
Innovation Solution
A thermal management system utilizing a conventional refrigeration loop that reconfigures coolant paths to efficiently manage heating and cooling by utilizing ambient air and waste heat, incorporating a compressor, condenser, expansion valve, and evaporator, with hydraulic 4-way valves to direct coolant flow through various channels based on temperature differences and ambient conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by stationary object
If electric coolant heaters are used to heat the battery and cabin in cold weather, then heating function is provided, but the Coefficient of Performance (COP) is limited to 1
Solution Approach 1:
The patent introduces a refrigeration loop with refrigerant as an intermediary substance to transfer heat between the battery, cabin, and ambient air. The refrigerant circulates through evaporators and condensers, enabling heat pump operation that achieves COP > 1 by extracting heat from ambient air and transferring it to the battery and cabin, rather than directly converting electrical energy to heat through resistors.
Solution Approach 2:
The patent utilizes phase transitions of the refrigerant (evaporation and condensation) to enable efficient heat transfer. The refrigerant evaporates at low temperature to absorb heat from the ambient air or battery, then condenses at higher temperature to release heat to the cabin or battery, leveraging the latent heat of phase change to achieve high COP heating.
2Use of energy by stationary object
If heat is extracted from ambient air using a heat pump system, then heating COP can reach 3, but the system becomes complex with multiple expansion valves, evaporators, sensors, and condensers in parallel
Solution Approach 1:
The patent designs a universal refrigeration loop that can operate in multiple modes (heating, cooling, battery thermal management) using the same core components. The refrigeration loop serves both cabin climate control and battery thermal management functions, eliminating the need for separate heating and cooling systems and reducing overall system complexity despite achieving high COP heating.
Solution Approach 2:
The patent employs dynamically controllable flow control valves that can redirect refrigerant flow between different paths based on operating conditions. This dynamic flow control allows a single evaporator and condenser to serve multiple functions, replacing the need for multiple fixed parallel components, thereby reducing system complexity while maintaining high COP heating capability.
3Use of energy by stationary object
If a complex refrigerant network with multiple components is used to deliver heat to the cabin and battery, then heating capability is improved, but the number of leak points for high-pressure refrigerant increases
Solution Approach 1:
The patent merges the cabin heating and battery thermal management functions into a single integrated refrigeration loop. By combining previously separate systems into one unified refrigerant circuit with shared components (compressor, condenser, evaporator), the total number of potential leak points is reduced while maintaining the ability to provide both heating and cooling functions to both cabin and battery.
4Use of energy by stationary object
If the battery is used as the heat source for coolant heating, then heating function is provided, but the drive unit temperature increases which is not desirable
Solution Approach 1:
The patent converts the ambient air, which is typically a heat sink that must be cooled, into a heat source for heating the battery and cabin. The refrigeration loop's evaporator extracts heat from ambient air, and this extracted heat is then transferred to the battery and cabin through the refrigerant cycle, turning the ambient air from a harmful cold environment into a beneficial heat source, achieving high COP heating without overheating the drive unit.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This system enhances heating efficiency by maximizing the use of ambient air and waste heat, reducing refrigerant system complexity, and maintaining battery and cabin temperatures effectively, while minimizing heat rejection and collateral heating/cooling.
Implementation Method 1
a refrigeration loop including a compressor, a condenser, an expansion valve, and an evaporator
Implementation Method 2
the condenser adds heat to the coolant in the drive unit channel
Implementation Method 3
a refrigeration loop including a compressor
Implementation Method 4
an expansion valve
Implementation Method 5
the evaporator removes heat from the coolant in the chiller channel
Implementation Method 6
the condenser adds heat to the coolant in the drive unit channel
Data Source
AI summary
A thermal management system designed to provide efficient sources of heating and/or cooling to the battery and/or the cabin taking advantage of ambient air and/or waste heat from power electronics. A primary way that the system provides efficiency in thermal management is the ability to reconfigure the path that circulated coolant follows through the system's channels. By using the processes and systems described herein, efficient thermal management can be achieved.