Electromobility and Electric Vehicles: Challenges and Trends

February 23, 2021 – Reading time: 5 minutes

Electric vehicles (EV) may seem like a modern discovery in today’s world of combustion engines, but their history goes back more than 180 years. The technology is now gaining in popularity for some of the same reasons as it was 180 years ago.

Excessive petrol dependence combined with the growing threat of global warming and the pressure of the environmental regulations on internal combustion engines (ICE) is leading automotive companies to invest more in electromobility. Although electric vehicles (EV) currently make up only a small percentage of global automotive sales the demand for them is increasing. Only in Germany, more than 190,000 electric cars are newly registered in 2020, according to the German Federal Motor Vehicle Transport Authority (KBA). This is an increase of 207% over 2019 and there is little evidence that this trend could slow down. As a technology consulting company with many years of experience in automotive industry, we want to take a closer look at the trends in electromobility.

Although electromobility sounds like a novel concept in today’s world of internal combustion engine vehicles, electric cars have been around for 180 years. The first electric car was developed in 1830s. When the performance of batteries was improved in the late 19th century, electric cars began to spread further. In fact, in the early half of the 20th century electric cars were sold better than internal combustion engines because they were quieter and easier to start and didn’t emit a smelly pollutant as gasoline cars [1]. But advances in combustion engine technology and the cheap mass production of oil-powered vehicles put an end to the rise of the electric vehicles.

However, developments in battery technologies and electric drives, higher oil prices and efforts to limit climate change have put electric vehicles back on the agenda in the 1990s.

Despite developments in the electromobility industry, consumers are still concerned about the following aspects of the electric vehicles:

Range is a market-specific factor influencing consumer choice of electric vehicles. Thanks to the higher energy density of lithium-ion batteries due to the improvements in materials and design, the 500 km range mark has already been exceeded for some vehicle models. For example, Tesla model S (2021) can even travel up to 652 km on one battery charge, according to its current performance and range specification. On the other hand, extending the range of electric vehicles requires more energy to be stored. This in turn influences factors such as cost, size and weight of the vehicles.

For potential customers of electric vehicles, it makes a significant difference whether they must wait half an hour or a whole night before continuing their journey. The charging capacity of the charging infrastructure, the capacity of the battery and the charging technology of the electric vehicle all play a role in the charging time. If we talk about the charging infrastructure, the charging process, for example, takes 8 to 14 hours on average with a 2.3 kW household socket whereas it takes only 2 to 6 hours with a home wallbox charger which can supply a power of from 3.6 kW up to 22 kW. On the other hand, the charging time is reduced to 30 minutes for public fast-charging stations [2]. Nevertheless, it is still much longer than that of the ICEs.

The availability of charging stations is also a significant factor in the decision of potential customers in favor of electric vehicles. In cities, this is less problematic as the driver can travel comfortably with a full battery charge. The big problem is the long-distance traffic where the charging stations are not available in sufficient number and density. That’s why many people fear that the battery will be empty before they reach their destination.

The trends show that the challenges can be overcome in the future thanks to the developments in energy storage and the design.

The big OEMs are increasingly developing electric vehicles on dedicated EV platforms. In 2015, Volkswagen already began developing the Modular Electrification Toolkit (MEB). The MEB is one step towards realizing its TRANSFORM 2025+ strategy of selling at least 1.5 million electric vehicles per year by 2025 [3]. The advantages of EV platforms over ICE platforms are longer ranges and a larger interior. The platforms for ICEs are not suitable for electric vehicles and therefore have a limited energy storage capacity compared to vehicles based on EV platforms. The battery of EV platforms, on the other hand, can take a simple rectangular shape and provides the vehicle up to twice the range. In addition, the battery can be placed at the vehicle base. This not only provides a higher stability to the vehicle, but also saves a lot of space in the interior.

Figure 1. Comparison of battery pack architectures on ICE and EV platforms

To meet the requirements of electromobility OEMs are focusing not only on design, but also on reduction of charging times and weight as well as extending battery life and increasing battery energy density. By optimizing the cell chemistry and introducing new battery cell materials, electric vehicle manufacturers aim to improve the energy density and thermal performance of lithium-ion batteries. In addition, advances in battery management systems in the future will help to increase the vehicle range and extend the battery life.

Supercapacitors are a relatively new field of research in the electric car industry. Supercapacitors are a type of energy storage device and, like batteries, have a positive and negative electrode separated by an electrolyte. However, unlike batteries, supercapacitors store energy electrostatically, not chemically. Compared to a battery, supercapacitors have a higher power density which means faster charging and discharging cycles [4]. Therefore, they are ideal for intensive applications, e.g. the supply of an accelerating car. This is why they are also used to absorb the short-term energy generated during braking. Despite their advantages, supercapacitors are not yet a substitute for batteries due to their relatively low total energy. Thanks to research in this area, however, this may change in the future. This thesis is supported by the recent acquisition of a manufacturer of these supercapacitors by Tesla.

Electric cars represent great potential for the future. Thanks to the developments in this industry of electromobility, we will have to change our understanding of mobility.

[1] K.V. MURALIDHAR SHARMA, MANOJ R KULKARNI, VEERENDRA G.P, KARTHIK N, Trends and Challenges in Electric Vehicles. International Journal of Innovative Research in Science, Engineering and Technology, 2016, Vol. 5, Issue 5

[2] AutoScout24. [2020-07-09]. https://www.autoscout24.de/informieren/ratgeber/elektromobilitaet/laden-und-verbrauch/laden-verbrauch/

[3] Volkswagen AG. [2020-03-18]. https://www.volkswagenag.com/en/news/2020/03/volkswagen-brand-about-to-leap-into-the-electric-era.html

[4] Interesting Engineering [2020-06-06]. https://interestingengineering.com/could-ultracapacitors-replace-batteries-in-future-electric-vehicles

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