Understanding 5 Types of Cooling Systems in EVs and HEVs

Thermal management for electric vehicles (EVs) and hybrid-electric vehicles (HEVs) ensures battery safety and vehicle performance. Indeed, these cooling systems address the heat during battery discharge and charging. Different cooling system designs have materialized as EVs and HEVs have progressed, including liquid, air, phase-changing material, and thermoelectric cooling. Each tackles unique challenges of thermal management for electric vehicles.

For instance, with its better heat conductivity, liquid cooling upholds prime battery operating temperatures to extend battery life and inhibit thermal runaway. Remember, batteries can rupture or catch fire if overheated in this condition. Developing these cooling systems also features their role in preserving efficiency under erratic environmental conditions. It has become an indispensable aspect of thermal management for electric vehicles.

5 Types of Cooling Systems in EVs and HEVs

What types of cooling systems do EVs and HEVs have? Let's have an overview of each kind.

Air Cooling Systems

While utilizing the air from the environment, air cooling systems in EVs and HEVs work with convection. The process involves drawing in cooler external air to circulate the battery system. It absorbs heat and expels the warm air. Their simplicity and cost-effectiveness are notable since these systems don't require complex parts or expensive coolants. However, their effectiveness in heat dissipation is limited. Because air has lower thermal conductivity, air cooling systems struggle to manage the intense heat from contemporary, high-performance batteries. It renders them less appropriate for vehicles that mandate higher power output.

Liquid Cooling Systems

Liquid cooling systems in EVs and HEVs are more advanced. They use a coolant like a glycol-based solution to absorb heat. The system has a network of pipes to circulate the coolant around the heat-generating components. It also comprises a pump for moving the coolant and a radiator to cool down the heated coolant. The efficiency of liquid cooling systems depends on the liquid's higher thermal conductivity and heat capacity. It facilitates more effective heat absorption and management. Although the system is more compound and costlier than air cooling, it gives better thermal management for electric vehicles.

Fin Cooling Systems

Fin cooling systems in EVs and HEVs use cooling fins to enlarge the surface area for heat transfer. The battery cells attach the fins for heat transfer from the batteries to the fins and the surrounding air. While this system boosts the cooling effect thanks to the increased surface area, it also introduces added weight to the vehicle. It might be a deliberation because it impacts the vehicle's performance. Hence, fin cooling systems balance effectiveness and simplicity, but they may not be perfect for vehicles where weight is critical.

Phase Change Material (PCM) Cooling Systems

PCM cooling systems in EVs and HEVs utilize the properties of phase-change materials that absorb heat during their transition from solid to liquid. Therefore, it helps them keep a stable temperature within the battery pack. While PCM systems absorb heat and can attain uniform temperature distribution, they have boundaries. The primary challenge is the volume change during the phase transition and the system's incapacity to transfer heat away. Consequently, it could be a shortcoming in scenarios requiring rapid and constant heat dissipation.

Refrigerant-Based Cooling Systems

Refrigerant-based cooling systems in EVs and HEVs integrate with the vehicle's air-conditioning system. These systems use refrigerants to absorb and transmit heat from the battery cells. The integration allows for a more well-organized management of battery temperature with the cooling capacity of the vehicle's existing HVAC system. The efficiency of these systems is notable in that they can uphold the finest battery temperatures under capricious operating conditions. However, the complexity and integration with the HVAC system may be more tricky and expensive to keep than more straightforward cooling systems.

Challenges and Maintenance in Cooling Systems

The following are the common challenges of thermal management for electric vehicles.

• Leakage: In liquid cooling systems, pipe mutilation can cause coolant leakage. It affects the system's efficiency and prompts overheating.

• Corrosion: Over time, glycol-based coolants can cause corrosion within the cooling system. It impacts the thermal management for electric vehicles.

• Clogging: Accumulating debris or using old coolant in liquid cooling systems can result in choking. It deters optimal thermal management.

• Extreme Temperatures: EVs face challenges in punishing temperatures; air cooling systems may struggle in hot climates. It affects thermal management effectiveness.

Maintenance Tips for EV and HEV Cooling Systems

Regular and systematic maintenance is key for effective thermal management for electric vehicles. First of all, routinely check for any signs of leakage in the liquid cooling system and verify that coolant levels are passable. Replace coolants as the manufacturer recommends, normally every five years, to circumvent corrosion and clogging. Furthermore, confirming that air filters are clean and unobstructed for vehicles with air cooling systems is vital.

More frequent checks may be necessary in regions with risky temperatures so the system is functioning optimally. Monitoring the battery's temperature can also provide early indicators of impending cooling system issues. For example, in some Tesla models, the liquid cooling system is designed around the battery pack for resourceful thermal management. Remember, keeping an eye on the system's performance can preempt maintenance requirements.

Evolution and Integration of Cooling Systems in EV and HEVs

The thermal management for electric vehicles incorporates varied cooling systems for their needs. In EVs and HEVs, cooling systems manage the heat from batteries and other electronic components. They range from air cooling to more multifaceted liquid cooling systems. Some unconventional models integrate phase-changing materials or thermoelectric cooling. For instance, the Toyota Prius (a series-parallel hybrid) uses a system comprising multiple cooling circuits. Meanwhile, the Chevrolet Bolt (a purely electric vehicle) employs a more straightforward arrangement thanks to the absence of an internal combustion engine.

Importance of Balancing Complexity and Efficiency

Thermal management for electric vehicles needs a balance between complexity and functionality. The cooling system must meet the vehicle's specifications and performance requirements. While more complex, liquid cooling systems offer greater efficiency to uphold steady battery temperatures. Still, their complexity adds to the vehicle's weight and requires careful upkeep. In contrast, air cooling systems are preferred for their simplicity and lower cost but may not provide sufficient cooling for high-performance EVs or in risky climates.

Influence of Technological Advancements on Cooling Systems

Tech advances have affected EV and HEV cooling system development and optimization. Novelties in battery technology, materials science, and electronic controls have braced more efficient and compact cooling solutions. Smart thermal management systems can adjust cooling parameters per real-time data and have heightened the reliability of EV batteries. New cooling mediums and designs, including dielectric coolants and microchannel liquid cold plates, reveal the nonstop efforts for better thermal management for electric vehicles.

T-Global's Solutions for EV and HEV Cooling Systems

T-Global specializes in thermal management for electric vehicles and other forward-looking electronics. Their product range includes unique items like ceramic heat sinks, non-silicone thermal putties, and cutting-edge phase change materials. While underlining early collaboration in the product design phase, they offer consulting and technical solutions for better product efficiency. T-Global's proficiency in thermal management is bolstered by its worldwide presence and 24/7 engineering support for custom solutions for client needs.