ICE vehicles ignite and combust fuel within an internal combustion engine (ICE). Electric vehicles (EVs) are powered by the electricity from a rechargeable battery instead. These are well-known and important differences, but did you know that ICE vehicles and EVs also share many components in common? For example, they both have gears and electric motors, use transmission fluid and coolants, and have braking and safety systems. Designers of ICE and electric vehicles are also adding an increasing amount of electronic content that can cause electromagnetic interference (EMI).
ICE Vehicles and the Electrification of Everything
For engineers in the heavy equipment and transportation industries, the electrification of everything can present challenges both old and new. For example, designers of diesel-powered equipment have long wanted to reduce the amount of engine noise that reaches the cabin. Electric vehicles eliminate engine noise because they use a battery, but EVs still need acoustic insulation because road noise now seems more pronounced. Regardless of a vehicle’s powerplant, problems such as buzz, squeak and rattle (BSR) from a faulty door or window seal also remain unwelcome.
Elasto Proxy understands the challenges that vehicle designers face and provides custom solutions to original equipment manufacturers (OEMs) in the heavy equipment and transportation industries. We also work with electric car companies that need industrial rubber products for applications ranging from EV battery boxes to charging stations. The main difference between ICE vehicles and EVs is about what generates the power for movement, but there’s so much more to consider. The table below and the sections that follow provide a comparison.
Table 1: ICE Vehicles vs. EVs
Internal Combustion Engine (ICE) Vehicle | Electric Vehicle (EV) |
High specific energy fuel | Low specify energy of battery |
Emits greenhouse gases | No tailpipe emissions |
Travels >600km / fill | Travels <250km / charge |
Short refilling time (<5 min.) | Long charging time (0.5 to 8 hrs.) |
Fuel tank takes relatively little space | Battery takes large space |
Fuel weight is low | Batteries are very heavy |
Higher maintenance cost | Lower maintenance cost |
Braking energy is not recovered | Can recover braking energy |
Running cost: high | Running cost: low |
Energy efficiency: 30% | Motor efficiency: 80% |
Needs complex gear system | Needs only one gear |
Noisy operation | Quiet operation |
Ample refilling infrastructure | Lacks charging infrastructure |
Need to pick up speed to deliver maximum torque | Produces maximum torque |
Uses only hydrocarbons | Uses electricity from many sources |
Electric Motors and EMI Shielding
ICE vehicles and electric vehicles both use electric motors, devices that supply motive power to either the vehicle itself or to another system. EV motors are larger than ICE motors, but both of these motors have two parts: a rotor that turns, and a stator that does not. In ICE vehicles, the stator touches the rotor through brushes and a commutator. A chemical reaction in the battery generates direct current (DC), which produces a magnetic field and spins the rotor. This rotation is transferred to the engine until the first ignition. Once the engine is started, rotation is transferred into motion.
In EVs, the stator does not touch the rotor. A chemical reaction in the battery generates DC current, but this DC is converted into alternating current (AC). In turn, the AC creates a magnetic field that causes the rotor to spin and transfers this rotation into movement. In both ICE and electric vehicles, there are electromagnetic fields between the rotor and stator. ICE vehicles generate these fields for just a short period of time, but EVs generate fields that are stronger and last longer. Consequently, EV designers need EMI gaskets to seal and insulate housings and enclosures for sensitive electronics.
Chemical Energy and Energy Density
ICE vehicles and EVs both convert chemical energy into motion. For the internal combustion engine, this chemical energy comes from a fuel like gasoline or diesel. With EVs, the chemical energy comes from a rechargeable battery. Because gasoline and diesel are relatively lightweight but produce a high amount of power, they have high energy density. By contrast, EV batteries are heavy (500 kg) and have a low energy output. Consequently, EV power sources have a relatively low energy density – a potential problem with heavy trucks, trains, or buses that need significant energy to move a load.
Electric vehicles use a lower-density energy source, but EVs also use lighter weight components. For example, in many diesel-powered heavy trucks, door seals are made of EPDM rubber, an economical and weather resistant elastomers. Thermoplastic vulcanizate (TPVs) elastomers weigh significantly less than thermoset EPDMs and are finding applications in electric vehicles. High-performance TPVs with high heat resistant and excellent oil resistance are also used in under-the-hood ICE applications.
Efficiency, Torque and Weight
There are also differences between ICE vehicles and EVs in terms of efficiency. ICE vehicles convert the reciprocating, or up-and-down, movement of pistons into rotary motion. This conversion causes a major loss of efficiency and produces significant friction and vibration. Electric vehicles don’t need to convert reciprocating motion into rotary motion because the EV’s electric motor is already spinning. This leads to a 50% gain in efficiency (30% for ICE vs. 80% for EV) with only minimal friction and vibration. There are also differences in torque, a measure of the force that causes an object to rotate on an axis.
Vehicles with internal combustion engines have multiple gears, including for low and high speeds, to meet revolutions per minute (RPM) requirements for torque. The speed of rotation is controlled by the throttle, and the RPM range for optimal torque is between 2000 and 8000. By contrast, electric vehicles have only one gear and support a wider range of RPM. The speed of rotation is controlled by the frequency of the AC current, and the range for optimal torque is between 0 and 20,000 RPM. With their heavy batteries, however, the weight of a typical EV (610 kg) exceeds that of an ICE vehicle (240 to 480 kg).
Environmental Sealing and Thermal Insulation
Both ICE and electric vehicles need industrial rubber that can provide strong environmental resistance. Rain, snow, dirt, rust, road salt, and other contaminants from outside the vehicle need to be sealed-out and automotive fluids need to be sealed-in and kept clean. Compared to ICE vehicles, EVs store less liquid. There’s no fuel tank, of course, but EVs also need less transmission fluid. During the seal design process, however, it’s important to consider if an EV will be exposed to different types of chemicals.
Finally, vehicle designers need to keep in mind that EV battery packs must be kept cool during recharging. If one of the batteries in a pack overheats, the potential thermal runaway may ignite the other batteries in the pack. These battery packs are also sensitive to puncture and, once pierced, can leak electrolytes. Punctured batteries may also overheat when charging. High heat is also a problem with 5G electronics, which have higher densities and are expected to further revolutionize the transportation industry.
Do you need seals, gaskets, or insulation for internal combustion engine (ICE) or electric vehicles (EVs) that are used in the transportation or heavy equipment industries? Talk to Elasto Proxy and tell us what you need.