How are EV car batteries cooled?

Electric vehicle batteries are primarily cooled with active liquid cooling in a closed loop, though some smaller or legacy systems rely on air cooling or immersion cooling in niche cases.

Behind the headline fact, battery thermal management is a careful balance of keeping cells within an optimal temperature window to maximize performance, safety, and longevity. A dedicated thermal management system pumps coolant through the pack, exchanges heat with the outside air, and can also heat the battery when conditions are cold. The goal is to prevent hot spots during rapid charging and heavy driving while preserving battery life over years of use.

How the cooling system works

The following overview highlights the core components and their roles in cooling an EV battery pack.

• Sealed coolant loop: A glycol‑water mixture circulates through the pack, absorbing heat from the cells.


• Cold plates or cooling channels: Direct contact surfaces attached to battery modules transfer heat from cells into the coolant.


• Radiator or heat exchanger: Heat is dumped from the coolant to the outside air, typically via fans or a dedicated radiator assembly.


• Battery Thermal Management System (BTMS) and BMS integration: The BTMS controls flow, temperature, and heating, while the BMS monitors sensor data to optimize performance and safety.


• Pump, reservoir, and hoses: The pump drives coolant through the loop, with reservoirs and tubing connecting components and managing pressure.


• Heater for cold climates: An electric heater (and sometimes recovered waste heat) warms the battery to an optimal starting temperature in cold weather.


• Sensors and control algorithms: Temperature sensors placed at various points feed data to the control system to adjust pump speed, valve positions, and fan speed in real time.


• Auxiliary cooling paths and redundancy: Some designs include secondary cooling loops or extra radiators for high-demand scenarios, such as fast charging or extreme ambient conditions.

Together, these elements form a closed, actively managed system that can respond to changing driver demands, climate, and charging profiles. The result is more consistent performance and slower degradation than passive cooling alone.

Other approaches and edge cases

While liquid cooling is the standard for most modern EVs, there are alternate approaches and niche implementations worth noting. Some prototypes and specialized vehicles explore immersion cooling, where battery packs are submerged in dielectric liquids, and a few experimental or lower-volume designs test direct phase-change cooling or advanced passive cooling methods. In everyday consumer EVs, though, liquid cooling remains the dominant solution due to its effective heat removal, controllability, and reliability across climates and driving styles.

Air cooling

Air cooling relies on ambient air to remove heat, sometimes assisted by heat sinks or fans. It’s simpler and cheaper in theory but generally less effective for high‑power charging and sustained high‑load driving. Most mass‑market EVs have moved beyond pure air cooling to liquid systems for better temperature control.

Immersion cooling

Immersion cooling, using dielectric liquids to submerge parts of the pack, can offer excellent heat transfer and potentially simpler plumbing. It remains limited to select projects and is not widely deployed in mainstream passenger EVs as of the mid‑2020s.

Direct vs indirect cooling

In direct cooling, coolant flows in direct contact with battery cells (via plates or jackets). Indirect cooling uses cooling plates or channels that absorb heat without exposing the cells to the coolant. Most production EVs use indirect cooling with cold plates or internal channels designed to optimize uniform heat removal and protect cell integrity.

Temperature targets and why cooling matters

Manufacturers typically aim to keep battery temperatures within a narrow band, often roughly in the 20–40°C range during operation, with warmer conditions during heavy use or fast charging. In very cold climates, the system can actively heat the pack to around 20–25°C before charging or high‑demand driving begins. Maintaining appropriate temperatures helps preserve energy capacity, prolong cell life, and reduce safety risks such as thermal runaway. Excessive heat accelerates degradation and can shorten battery life, while too much cold can reduce instantaneous power and charging efficiency.

In practice across models

Nearly all mainstream electric vehicles rely on an active liquid cooling loop, tailored to the car’s pack design, power output, and climate. The exact layout varies by manufacturer and model, but the underlying principle is consistent: a closed coolant loop with cold plates or channels, a radiator or heat exchanger, and a control system that coordinates cooling and heating to keep the battery within its optimal temperature range. This approach supports fast charging, sustained high‑power acceleration, and long-term battery health across diverse driving conditions.

Impact on performance and longevity

Effective thermal management directly influences charging speed, peak power, driving range consistency, and long‑term battery longevity. By avoiding hot spots and excessive temperatures, manufacturers can maintain higher usable energy capacity over time and reduce the risk of accelerated degradation. Conversely, inadequate cooling can lead to reduced performance, slower charging, and accelerated wear.

Summary

Most electric vehicles rely on a sophisticated liquid cooling system to manage battery temperature: a closed loop with coolant, cooling plates, a radiator, and a smart control system that heats or cools as needed. While air cooling and immersion cooling exist in niche contexts, liquid cooling remains the standard for balancing performance, safety, and longevity across climate and usage scenarios. A well-managed thermal system helps EVs deliver reliable power, efficient charging, and longer battery life.

What is worse for the environment, gas or electric cars?

No, electric cars (EVs) generally pollute less than gas cars over their lifetime, although their initial manufacturing, particularly the battery, is more carbon-intensive. The total emissions of an EV depend heavily on the source of the electricity used for charging, and studies show they have a lower overall lifecycle greenhouse gas emission compared to gas cars. 
Electric vehicles

• Manufacturing: Building an EV creates more carbon emissions due to the energy-intensive process of creating the battery. 
• Operation: EVs have zero tailpipe emissions, meaning they do not release pollutants while driving. 
• Overall impact: When considering the total lifecycle, from manufacturing to operation to disposal, EVs have a smaller carbon footprint, especially if charged with electricity from renewable sources. 

Gas cars

• Manufacturing: Manufacturing a gas car has a lower initial carbon footprint compared to an EV. 
• Operation: Gas cars produce tailpipe emissions from burning gasoline, which are a major source of air pollution. 
• Overall impact: The total lifecycle emissions of gas cars are higher than EVs due to the constant emissions from burning fuel. 

How to cool down an EV battery?

Battery packs can be cooled using either air cooling, where heat is dissipated into the surrounding air, or liquid cooling, which involves circulating a coolant through the battery pack to facilitate efficient heat transfer.

How do electric cars cool their batteries?

EV battery cooling systems use air, liquid, or phase-change materials to manage temperature for performance and longevity. The most common systems are air cooling, which uses fans to circulate air, and more efficient liquid cooling, which circulates a coolant through a closed loop around the battery cells. Advanced techniques like direct liquid cooling immerse cells in a special fluid for maximum heat dissipation. 
This video explains how different types of EV cooling systems work: 51sThe Buzz EVYouTube · Feb 6, 2024
Types of cooling systems

• Air Cooling: A simple and inexpensive system that uses fans to blow air over the battery pack to dissipate heat. It is less efficient than other methods and is typically found in older or lower-performance EVs. 
• Liquid Cooling: The most common system in modern EVs, especially high-performance models. 
  • A coolant (like water and glycol) is circulated through tubes or channels in the battery pack. 
  • The coolant absorbs heat from the cells and then flows through a radiator to dissipate the heat. 
  • This method is more efficient at managing heat. 
• Direct Liquid Cooling: A more advanced and highly efficient method where battery cells are fully submerged in a special, non-conductive dielectric fluid. This allows for superior heat transfer from the entire surface of the cell. 
• Phase-Change Cooling: Uses a material that absorbs heat as it changes from a solid to a liquid state. The material is placed in contact with the battery cells, absorbing heat and helping to maintain a stable temperature. 

You can watch this video to learn how a direct liquid cooling system works: 1:23Garvin Mark EmamdieInstagram · Jan 22, 2025
Why cooling is important

• Proper thermal management is crucial for a battery's performance, longevity, and safety. 
• Consistent temperature helps the battery deliver its maximum range and charge efficiently. 
• Extreme temperatures, whether hot or cold, can degrade the battery over time. 
• Efficient cooling is especially critical during fast charging and high-power output to prevent damage. 

This video demonstrates how EV battery cooling systems work and the importance of thermal management: 0:26Shayan_EVYouTube · Nov 9, 2024

How does Tesla keep its batteries cool?

A cooling system is built into the battery and an external electric pump circulates coolant to maintain the correct temperature.