Electric vehicle battery temperature during hot weather

Electric vehicle battery temperature during hot weather

Electric cars have intuitive battery systems that are very different from traditional combustion-based engines. These batteries can generate high volumes of electrical energy, providing the vehicle with enough power to perform at optimal levels over a long lifespan. We’ve seen a very sudden increase in the volume of electric cars on the roads, primarily due to social factors as we begin to recognise the importance of cleaner energies, reducing pollution and reaching net zero. 

Lithium-ion batteries are the most common type of rechargeable battery system within electric cars. They have high power-to-weight ratios and are consistently being developed into smaller, lighter packs in order to enable better vehicle performance. Due to the intense growth and demand for electric vehicles, the battery storage technology is constantly being developed and tested with the aim of finding solutions to further improve their overall efficiency and safety. 

A major component of EV batteries is their insulation, as they can reach extremely high temperatures over long periods of time. Therefore they require exceptional insulating materials and technology, so that they remain safe for passengers and long-lasting. At Elmelin, we provide support and insulation solutions for the automotive industry, namely battery electric vehicles. Our mica-based insulation products have outstanding thermal and dielectric properties, improving the long-term safety of these batteries, as well as high versatility allowing for unique specifications to be met.

Numerous factors can impact the performance and lifespan of electric vehicle batteries. These can include overcharging or high voltages, deep discharges or low voltages and temperature. While UK summer weather conditions are unpredictable at best, it is worth considering the impact of high temperatures on electric cars in summer, and how battery storage insulation can help mitigate these challenges.


Effects of high temperatures

It is predicted that British summer temperatures will continue to rise sharply in the year ahead, with extreme weather conditions becoming more frequent and intense. We are experiencing temperatures of 25-30°C more often, and with this, there are implications for electric car manufacturers to assess. Hot weather can have negative effects on various EV components, namely the battery. EV batteries can function at higher temperatures, but the range and performance may start to diminish. 

These batteries have a battery management system (BMS) which changes the charging rate in relation to the internal temperature of the battery. At higher temperatures, the charging rate starts to decrease. The risk of overheating is exacerbated during hot summer weather, especially if the vehicle is in direct sunlight for large parts of the day, e.g. on driveways or in outdoor car parks. If there is a heatwave in the region of >35°C, which from the predictions might not be entirely unrealistic, then BMS can be forced to entirely halt charging for safety reasons. 


Cooling systems

With the rise in electric vehicles and battery storage solutions, manufacturers and engineers implement cooling systems and insulation to help reduce electric vehicle battery temperature, whilst also containing them. Nowadays, battery cooling systems are standard features in electric vehicles, and there are multiple variations of these systems available:

Two moderately uncommon types of cooling systems are phase change material and cooling fins. Phase change material functions by transitioning from solid to liquid state, where large amounts of heat energy is absorbed during this process. Cooling fins on the other hand use conduction and convection to transfer heat from the battery pack to the cooling fins and then from the fins to the air.

Two of the more customary cooling systems are air cooling and the use of liquid coolants. Air cooling is less effective, using convection to transfer heat away from the battery pack as air passes over the surface. The most efficient variation is the use of liquid coolants, which have greater heat conductivity and can store heat in the form of energy within bonds, reducing the overall electric vehicle battery temperature. 


Insulation solutions

As well as cooling systems, insulation plays an important role in regulating electric vehicle battery temperature. Automotive insulation solutions have evolved over the years and there are now multiple options available for electric vehicles. Insulation in EV batteries is intended for maintaining safety without compromising on the vehicle performance. Regardless of environmental factors such as weather, EV batteries reach high temperatures that require insulation to protect other components within the vehicle, and most importantly the passengers inside. 

In hot weather conditions, the need for efficient insulation becomes more apparent, as there is a greater risk of overheating, discharging and potentially thermal runaway. The high temperatures are further increased by external temperatures if the insulation within the battery isn’t up to standard. The expansion and changing of shape allowed by our Compression Pads Plus further benefits a battery’s condition during hot weather.



Of course, cooling systems and insulation aren’t the only ways of maintaining an EV battery during warm summer conditions. The vehicle owners themselves could use garages when available rather than leaving the vehicle on driveways, or reduce the amount of use by making shorter journeys or using alternate forms of transportation for longer journeys such as public transport. Furthermore, charging slower and at night can also help reduce the intensity of battery usage. 

Fortunately these days with the technology available, UK summers and hot weather aren’t as much of a problem as they may have been years ago. However, it is worth considering how the vehicle is being used and what conditions it’s being subjected to, especially over long periods of time. 

Elmelin supply innovative and sustainable solutions for the automotive industry, namely electric vehicles. Sustainability and safety are top priorities for us, and we work carefully with manufacturers to offer solutions that can help support these aspects. We use mica’s unique thermal and dielectric properties to provide insulation for EV batteries. Our Compression Pads Plus are available to extend the lifespan of EV batteries by providing outstanding insulation whilst also allowing the battery pack to expand and contract during operation.  If you have any questions or would like to find out more about the solutions we provide, please do get in touch here.