As the automotive industry undergoes rapid changes, electric vehicles, for one, have over time represented a fundamental shift that requires engineers from different fields to work together.
This blog provides professional engineers with detailed technical information about how electric vehicles (EVs) differ from internal combustion engines (ICEs) and how the EV revolution presents both design obstacles and possibilities for all engineering professionals.
Powertrain Architecture & Energy Source
The operation of traditional ICE vehicles requires multiple cylinder and piston units, together with crankshafts and multi-gear transmissions, as well as continuous fossil fuel consumption.
The propulsion system of battery electric vehicles (BEVs), for instance, operates with a battery, an inverter, a motor, and a single-speed gear system, resulting in reduced moving parts and a cleaner energy delivery process. The operation of EVs, on the other hand, depends solely on electrical energy storage for propulsion, but ICEs need to burn fuel to generate motion.
Even more, the hybrid vehicle family, which includes hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and fuel cell electric vehicles (FCEVs), demonstrates the ongoing transition toward electric vehicle technology.
Energy Efficiency & Performance in EVs vs. ICEs
The efficiency difference between these two power sources stands out as one of the most significant distinctions. The fuel energy conversion rate of internal combustion engines (ICEs) reaches between 12% and 30% while the remaining 70% to 88% causes heat and friction losses. The maximum efficiency of diesel engines reaches 40-45% when operating under perfect conditions.
While ICEs must increase their RPM before reaching peak torque and require gear shifts to maintain their most efficient operating range, EVs’ instant torque delivery from zero RPM produces quick and smooth acceleration.
EVs’ propulsion efficiency, when using electrical energy, reaches between 77% and 90%. This threefold gain in efficiency between EVs and ICEs delivers considerable advantages for both performance and environmental sustainability.
NVH and Component Engineering Differences
The reduced number of mechanical parts in EVs enables them to run with minimal noise output. However, the absence of engine noise reveals additional sound sources, which include gearbox chimes and wind or road noises and acoustic irregularities, thus making NVH (Noise, Vibration, and Harshness) engineering essential for EV design.
Moreso, the design of EVs requires specific components, such as gears, brakes, cooling systems, and seals, but they need additional elements such as electromagnetic interference (EMI) shielding and advanced features like thermal management systems, especially for motors and batteries, among other things.
Energy Storage, Range, & Refueling/Recharging Dynamics
The use of high-energy-density liquid fuels in ICE vehicles benefits from an existing worldwide refueling infrastructure. As such, the process of filling the tank requires only a few minutes.
On the other hand, the batteries in EVs can be burdensome because of their low energy density while charging times span from 30 minutes of fast charging to multiple hours.
Even more, fast-charging network development has accelerated yet people in specific areas continue to experience range-related concerns.
Systems Integration & Emerging Technologies
For the most part, EVs operate as cyber-physical systems that extend beyond their mechanical aspects:
- Grid Integration & V2G: The current market includes EVs that function as Vehicle-to-Grid (V2G) systems, which convert parked vehicles into power storage units for grid stability during peak usage periods.
- Advanced Sensing and Controls: The core elements of EV architecture include Battery Management Systems (BMS) and embedded safety protocols and telematics systems and advanced sensing technologies.
- Future Technology: The development of solid-state batteries and fast-charge technology, power electronics, motor materials as well as lightweight chassis materials will transform both electric vehicles and upcoming internal combustion engine hybrid vehicles.
Engineering Implications & Design Takeaways
Design Tradeoffs
The engineering process requires balancing four essential factors, which include weight optimization, NVH performance, thermal management, vehicle efficiency and safety, as well as maintenance capabilities.
Cross-Disciplinary Collaboration
EV projects require engineers from multiple disciplines to work together seamlessly between mechanical, electrical, thermal, materials, industrial, and systems fields, as well as chemical and metallurgical experts for sustainable materials and recyclability.
Lifecycle Thinking
As opposed to ICEs, EV engineering requires a complete lifecycle assessment. Handling raw material extraction for battery metals and production with renewable power and battery recycling or reuse, as well as vehicle maintenance throughout its operational period.
Continue Learning About EVs and Internal Combustion Engines
The fundamental distinction between EVs and internal combustion engines reaches beyond basic performance metrics because they operate differently in terms of efficiency and torque delivery, noise output, energy storage, and system integration.
Engineers need to understand these distinctions because they form the basis for creating a sustainable green economy.
The Fundamentals of Electric Vehicles course at McKissock Learning provides engineers with the opportunity to develop their expertise in this exciting field. This engineering continuing education course provides complete knowledge of EV production starting from material extraction through renewable energy plastic development and manufacturing assembly so you can identify your skills for advancing the EV industry.
