Five truths about the electric car

Despite a state purchase premium in Germany of up to 4,000 euros, most electric cars are still much more expensive to buy than diesel or gasoline vehicles. This is mainly due to the battery, which determines around 40 percent of the cost of an electric vehicle. However, prices for lithium-ion batteries fell by 80 percent between 2010 and 20161. Currently, the battery pack costs around 170 euros per kilowatt hour (kWh)2. From about 130 euros/kWh, the price of electric cars and gas burners would be the same. Experts expect that costs will continue to fall due to higher volumes and innovations in battery cell construction, and will come to match the price of the internal combustion engine. The Freudenberg Safety Separator helps to streamline the production process (see box). Because this separator can withstand high temperatures, it enables separators and electrodes to be dried in only one process step in contrast to polymer film separators. Incidentally, in operation, electric cars are already cheaper than fuel burners because they have fewer wearing parts and require no exhaust maintenance or lubricants.

2. Charging takes too long and there are too few charging stations.

It takes at least six hours to charge the battery using a standard household power outlet. That sounds like a lot, but it’s not a problem if the electric car charges in your own garage or at a charging station at work. Bear in mind that a private car stands idle for more than 21 hours a day on average. Long charging times are a shortcoming on the road, although charging stations with a fast-charge function require a maximum of an hour, sometimes less than 30 minutes to recharge the battery of an e-car. Nevertheless, there is still a shortage of charging stations. That is why for example the German state is providing 300 million euros to fund the construction of new charging stations. By 2020, the aim is to have built 5,000 new fast-charging stations and 10,000 charging poles using normal charging technology. Electric car batteries react similar to cell phone batteries: they become considerably warmer during fast-charging. Freudenberg’s temperature-stable separator can provide increased safety in this respect.

3. Electric cars are adversely affected by cold weather.

Frost is a challenge for electric cars. As with the combustion engine, cold conditions cause increased friction between all parts, leading to higher energy consumption. In addition, the battery not only needs to drive the car in winter but must also provide power to the lighting and heating systems. For this reason, the ADAC subjected three models – BMWi3, Nissan Leaf and Opel Ampera – to a winter endurance test in 2016. The results showed that the cars all worked flawlessly at temperatures as low as -20 degrees Celsius.

4. Lithium-ion batteries can catch fire.

In recent years, lithium-ion batteries in electric cars have occasionally caught fire or exploded. Although protective measures such as electronic battery management systems or thermal fuses largely prevent fires and explosions, the inherent battery safety has to be ensured previously. The use of temperature-stable cell components such as Freudenberg’s flexible and ceramic Safety Separator (see box) can reduce the risk of short-circuits causing fires. However, they cannot completely eliminate the risk of fire in the event of operating errors, design faults or accidents. Freudenberg’s ceramic-impregnated polyester nonwoven remains stable at high temperature and does not shrink. Consequently large-area short circuits in a battery cell are avoided and the “thermal runaway” in the complete battery system is prevented. In the event of a fire, electric and hybrid cars with lithium-ion drive batteries are at least at the same level of safety as petrol and diesel vehicles, according to the testing organization Dekra.

5. The life of the batteries is limited.

Manufacturers of batteries for electric cars currently guarantee mileages of 100,000 to 160,000 kilometers. Experts give the life of the battery as eight to ten years and 500 to 1,000 charging cycles. Precisely how long a battery lasts will depend on many factors, such as the number of charging cycles, the type of charging, the driving style or external conditions such as temperatures. After that, the battery doesn’t simply fail but loses charge capacity and thus range. After a few years, capacity drops to 70-80 percent although this process can be delayed by proper care. Avoiding extreme charge levels and having the battery inspected once a year will increase its lifetime.

More information about Freudenberg’s separator:

https://separators.freudenberg-pm.com