Temperature vs. battery life

Is it different to drive an electric car around Oslo and Barcelona?

Yes, and it all depends on how the battery behaves at different temperature extremes. Electric cars are growing in popularity, it is estimated that the battery market alone will reach about 900 billion by 2030. This is influenced not only by growing environmental awareness and formal and legal decisions, but also by technological developments that affect the comfort of this type of vehicle.

Effect of weather on battery life

When planning the purchase of an electric car, we consider many components. Some of them such as price, range or design are obvious, but when considering the purchase of a particular model, do we think about the factors that affect battery life? During a study conducted on a group of more than 6,300 electric cars (fleet and consumer) of various brands, 1.8 mill days of data were collected. Based on the processed telematics data, insights were gained into the conditions that actually affect battery health. The aggregated average degradation data came from 21 different vehicle models from 64 brands from different models dating back different years. The aggregated data shows that there is a relationship between temperature and battery range and life.

What is the average battery range?

Considering the performance life cycle and condition, the battery is a key component of an electric car. Moreover, the battery is its most expensive component and the degree of its wear directly affects the performance and consequently the range of the vehicles. Analyzing the parameters for batteries in electric cars, it is difficult to find clear information on what is the life of such a battery. However, manufacturers very often provide a guarantee in case of malfunction. According to the data collected, the average battery range is about 160934 km, which translates into 8 years of operation. From the point of view of customers, such guarantees are important and in a sense reassuring.

It should be noted that battery prices are falling year after year. Since 2010, the price of an average lithium-ion battery has dropped by more than 80%. The significant reduction in cost, combined with the manufacturer’s warranty, is convincing an increasing number of consumers, especially the undecided.

Impact of weather on electric cars

Among the most important factors affecting the condition of batteries for electric cars are service life, use at high/low state of charge, high electric current, power cycles (wear and tear) and just temperature.

The general opinion is that low temperatures are the biggest threat to battery life. Since the first electric cars appeared on the market, one of the most common failures has been functional problems precisely in winter. Analyzing, among other things, the ranges noted significant differences between vehicles used in Canada and those in Norway. The conclusion of this research was simple: the possible ranges depend on the temperature, the lower the temperature, the lower the ranges.

Because of the additional heating (and cooling), the daily range decreases. After all, the energy from the battery powers not only the vehicle, but also auxiliary systems mainly heating and cooling of the car cabin and the battery itself. It should also be noted that lithium-ion batteries are slower at extreme temperatures. Low values, on the other hand, affect their ability to store and release energy, which directly affects ranges more than the auxiliary load. One solution to minimize battery performance loss is for manufacturers to introduce battery temperature management systems.

Pioneering solution

Tesla is an excellent example of how manufacturers deal with the effects of temperature on batteries. In this case, two ways have been introduced. First, using an extensive temperature management system, it is possible to keep the battery within its optimal operating temperature range (it is heated in winter and cooled in summer). The second way is to calculate the range of an electric car usinga fixed capacity value instead of a dynamic value based on external factors.

Is it better to drive an electric car around Oslo or Barcelona?

Batteries in electric cars exposed to high temperatures are susceptible to more damage, but how big are the differences? To answer this question, the study used vehicles used in temperate zones, where there are less than 5 days per year where the temperature is below 27 C or below -5 C, and in hot zones (there are more than 5 days per year with temperatures above 27 C. Electric cars that were used in temperate zones had a much faster rate of battery decline than those traveling in temperate climates.

What is the ideal weather for electric cars?

21.5 C, because at this temperature it reaches its peak estimated value of 115%. Analysis shows that temperature alone can reduce range by as much as 10-12%. Interestingly, turning on the air conditioning can reduce the range by up to 40% while at -15 C they drop by 54% relative to their rated ranges, which means that a car that (under test conditions) could cover 402 km will actually drive an average of 217 km at such a temperature.

Demand for batteries is growing

As the popularity of electric cars grows, so does the battery market, estimated to reach $900 billion by 2030 . Regulations introduced by the European Union only confirm that this is not a temporary trend, but a permanent one. Strong interest will increase demand for lithium-ion batteries. Getting enough product to market will be a major challenge for the industry. Not only will it be necessary to build new factories, but also to automate and robotize existing production lines. Increasing production carries the risk of losing quality. Which can directly translate into not only financial or image losses, moreover, it can affect safety issues, which are extremely important. One of the ways how to prevent this is to constantly control production processes using vision systems. A properly built system consisting of a properly selected camera, illuminator and dedicated software system is able (without stopping production) in real time to control, among other things: the correctness of the arrangement of cells, orientation of batteries or binders, saving a significant amount of time.