Electrification is a mainstay of modern mobility, and thus regularly graces the news cycle with new regulations, partnerships, and technologies.
EVs are edging past novelty commodities toward mainstream adoption (although there is still a long way to go). Back in 2010, only a few thousand global passengers EVs were sold, according to the Bloomberg New Energy Finance (BNEF) 2019 EV forecast. Fast forward to 2018 and passenger EV sales topped more than 2 million.
BNEF analysts predict this upward trend shows no signs of slowing down. “We expect annual passenger EV sales to rise to 10 million in 2025, 28 million in 2030, and 50 million by 2040,” according to the BNEF report, “By 2040, we expect 57% of all passenger vehicle sales, and over 30% of the global passenger fleet, will be electric.”
With EV sales on the rise—all the while boasting clean and efficient transportation—the EV market presents interesting opportunities for engineers.
However, a fair amount of design challenges and improvements await those who enter this field of work. Let’s break a few of them down.
EV Battery Chemistries
Unlike conventional vehicles, electric cars rely on batteries to run everything, especially the controller which, in turn, runs the electric motor. Batteries store chemical energy and convert that into electricity. Various battery chemistries are available for the EV market, each carrying their own set of pros and cons. Lithium-ion (Li-ion) currently reigns supreme, possessing a combination of properties that is suitable for certain electric mobility applications. However, lead-acid (Pb-acid) batteries and nickel-metal hydride (Ni-MH) batteries are also in commercial use and offer benefits in specific situations.
If you thought the list stops there, think again. Many emerging battery chemistries are being tested, which include lithium-sulfur, lithium-air, zinc-air, nickel-cadmium, nickel-zinc, zinc-bromine, zinc-chlorine, sodium-sulfur, and sodium-metal chloride, just to name a few. Again, each possesses their own advantages and disadvantages.
Engineers are still testing the right mix of battery chemistries for targeted EV applications that will lead to wide adoption of clean, low-carbon transportation.
To achieve this, researchers are exploring beyond the conventional Li-ion option toward different battery chemistries with low cost and higher specific energy, according to the 2018 article “Batteries and fuel cells for emerging electric vehicle markets,” published in the journal Nature Energy.
Research into new battery systems is popular in academia, focusing on hundreds of different options, from metal-air batteries at the University of Waterloo to redox flow batteries from the University of Colorado, Boulder.
A lab prototype of CU Boulder's aqueous flow batteries. Image from the University of Colorado Boulder
In addition, high-utilization vehicles, such as public and goods transportation, are key contributors to harmful emissions. Therefore, they make for promising candidates to transition to electric mobility. Since these services rely on tight operational schedules, EV charging has to be fast. However, fast charging can increase cell degradation, cause safety issues such as flammability, and put strain on the power grid. High-utilization EVs require engineers to balance fast recharge times while also leveraging key safety and power features.
Test and Measurement
When converting a car into an EV, it’s not one size fits all. Different vehicles models have different technical specifications. Plus, fabricating each potential design and testing it for faults turns out to be quite the costly endeavor.
In the case of EVs, engineers are trying to figure out the best approach for road transport, electric power systems, and integration within the power grid. By exploring simulation software, different design decisions can be tested before the construction phase. Simulation has been used to test software, EV design, ECU development, as well as ensure the functionality of customized features without breaking the bank and elongating the development period.
Electrification in vehicles goes hand-in-hand with increased computerization. As explained by the Bureau of Labor Statistics, electric motors are responsible for considerations such as torque and motor RPM (revolutions per minute), the motor turns and make these adjustments via electrical current. Demand for big data sets, however, means that information on power efficiency and even vehicle usage is valuable to vehicle manufacturers. This means that vehicles increasingly require connectivity, especially as OTA (over the air) firmware updates become more necessary for protecting cars from security threats.
An estimation of the amount of data complexity associated with connected cars. Image courtesy of FASTR
While there's a wealth of opportunity associated with firmware development for automotive applications, there are also more demands on RF applications.
Amid the myriad of skills and duties EV engineering careers demand, engineers will have to develop new battery designs and improve current battery technologies, as well as develop and test electrical components and circuitry often through simulation software.
It’s fair to say that a lot of development is on the horizon in order for EVs to overtake their gasoline- and diesel-based counterparts. However, signs are pointing mainly toward the positive in the EV field, and current and prospective engineers should take note.
If you have experience in designing power systems for EVs, hop into the comments below and share your thoughts on how EEs need to be trained for this field.
Featured image used courtesy of Leo Cardelli.