Electric Vehicles: The Automobiles of the Future (eBook)

Otto Bischof, Ted Tanaka (Autoren)

eBook Download: EPUB

2021 | 1. Auflage
330 Seiten
Bookbaby (Verlag)
978-1-7334755-2-5 (ISBN)

Infos

In Electric Vehicles : The Automobiles of the Future, physicist and mathematician Otto Bischof and mathematician Ted Tanaka explain the necessity of electric vehicles given the Climate Catastrophe that we are in. The authors thoroughly explain all the important components of electric vehicles in an easy-to-read scientific manner and provide in-depth reading questions for the student. Special detail is given to all of the battery technologies that impact electric vehicles. Even details of current electric vehicles are given for potential car buyers. With a complete glossary, thorough index, and fabulous illustrations, this book is in a class by itself!

Textauszug

Chapter 1: A Comparison of EVs and ICEs:

Operation:

ICE and EV cars operate very differently. ICEs burn gas (gasoline) to power vehicles but electrical energy powers EVs.

ICEs:

Gas is pumped into the car’s gas tank at a gas station. The energy is produced when gas is burned in the engine cylinders. The burning process is a controlled combustion of an oxygen and gas mixture when carefully timed sparks ignite the mixture. The mixture is created when a measured amount of gas is injected into an intake manifold by fuel injectors or a carburetor where it is mixed with oxygen and then delivered to the engine cylinders. An ignition system creates and distributes the sparks to the top of the cylinders. Pistons are forced down when the gas explodes. The movement of the pistons turns a crankshaft, which powers the wheels.

EVs:

An EV is a much simpler machine than an ICE. To “fill up” an EV on charge, the charge flows from an electrical plug outlet to the EV’s battery. The battery then can produce electrical power to run an electric motor. In between the battery and the motor, there is a controller that manages the flow of electricity from battery to motor. Then the electric motor changes electrical to mechanical energy, which is used to turn the wheels.

Maintenance Costs:

An EV has less moving parts than an ICE. An EV’s powertrain includes a motor, a simple transmission system, a differential (some EVs do not have axles or a differential), a controller, and a battery, while an ICE’s powertrain includes an engine, a complex transmission, a driveshaft, a differential, and axles. Since an EV motor does not require a lubrication system, a fuel system, an ignition system, timing belt, a cooling system, or a smog control system, which are essential parts of an ICE, it does not need the following standard ICE maintenance services: oil and fuel change, oil and fuel filter change, tune-up and spark plug change, timing belt change, antifreeze change, cooling system fan belts and water pump change, smog test, or a catalytic converter and muffler change. There are a few maintenance services that both EVs and ICEs require. These services are tire rotation, brake care, transmission service, and sometimes, differential care. As to the brake care, the regenerative braking of EVs extends the life of EV brakes by almost a factor of two. The following maintenance services are specific to EVs: battery thermal management care and battery replacement. Although an ICE battery needs to be replaced every few years, an ICE battery replacement is not as costly as an EV battery replacement. An EV battery replacement can cost anywhere from $5,000 to $15,000, depending on the size of the battery, with an additional core charge of $1,000. Although an EV battery replacement is a costly service, most EV batteries have warranties for 8 years or 100,000 miles, and an estimated lifespan of 100,000 miles. In addition, it is expected that future battery costs will be lower, assuming that the current rate of advance of EV battery technology stays constant. Therefore, it is clear that if one considers all necessary maintenance costs for an ICE and all necessary maintenance costs for an EV, an EV’s maintenance costs are less by quite a margin.

Efficiency and Fuel Economy:

In an EV, electrical energy from the grid is stored in the battery as chemical energy. The battery converts chemical energy to electrical energy, which it delivers to the motor. The motor then converts the electrical energy to mechanical energy, which turns the wheels. The efficiency of an EV is about 60% since about 60% of the electrical energy from the grid reaches the wheels in the form of mechanical energy. Furthermore, in driving conditions where the regenerative brakes are used, the efficiency of the EV is increased to about 77%, since the regenerative braking system recovers about 17% of the energy lost.

In an ICE engine, energy produced by the combustion of gasoline is converted to mechanical energy. This mechanical energy from the engine turns the transmission, which turns the driveshaft. The driveshaft connects to the differential, which turns the wheels through the axles. The efficiency of the ICE is only about 20%, since only that percentage of the energy due to the combustion of gasoline reaches the wheels.

The efficiency of a vehicle shows in its fuel economy. Since the EV’s source of energy is electricity rather than gas, the fuel economy of an EV is measured in miles per gallon equivalent (mpg-e) rather than miles per gallon (mpg). This measurement is used because it makes it possible to compare the EV’s fuel economy to the ICE’s fuel economy. Most EVs today have a mpg-e of over 100, while the most economical ICEs have a mpg of about 35. Thus, the EV has an advantage over the ICE in both efficiency and fuel economy.

Safety:

All motor vehicles sold in the United States must meet Federal Motor Vehicle Safety Standards. Thus, EVs have met the same federal safety standards and possess all of the relevant safety equipment as ICEs. Crash test ratings from tests performed by the National Highway Traffic Safety Administration (NHTSA) indicate that EVs are as safe or safer than ICEs in a crash. Crash test results from tests performed by the Insurance Institute for Highway Safety indicate that EVs are more able to withstand a crash than ICEs. Two features that EVs have that ICEs lack are a lower center of gravity and extended crumple zones. Since EV batteries are heavy and located at the bottom of the car, EVs resist rollovers and are less likely to flip over in a crash. In addition, EVs have less moving parts to take up space, which allows engineers to incorporate crumple zones to absorb the energy of collisions. The Tesla Model S, for example, has a trunk in the front which serves as an extended frontal crumple zone where an ICE’s engine would normally be.1

Another major concern regarding EVs is their propensity to catch on fire. Several design features limit this possibility. EVs are built with circuit breakers, which open electrical circuits, when sensors indicate a collision is likely to occur. Otherwise, collisions could cause a battery to heat up and explode, because the organic electrolytes used in most lithium-ion batteries are flammable. If a collision punctured a separator between plates of opposite polarity in a battery cell, liquid electrolyte could flow through, making a “short circuit”, which could potentially cause a fire. Tesla has reinforced the bottoms of their EVs with thicker metal barriers to prevent this from happening. Some EV companies like Tesla also help to keep fires from spreading by keeping groups of battery cells in isolated, protective compartments. Battery cooling systems also reduce the risk for fire due to excessive charging, discharging, or hot environments.

ICE cars have lead-acid batteries, which can also cause fires or explosions. If built-up hydrogen gas accumulates inside the battery due to improper venting, an explosion can occur, when a spark of electricity is produced nearby. Moreover, the full tank of gas can explode if any spark is fed to it. Sometimes these sparks can be caused by a collision or a “short circuit”.

EV’s reputation of catching fire easily is unsubstantiated by nationwide statistics. Statistics from the National Fire Protection Agency (NFPA) have shown that ICEs are more likely to catch fire than EVs. Therefore, as to overall safety, EVs should be considered as safe or safer than ICEs.

Price and Costs:

On average, for comparable vehicles, EV purchase prices are higher than ICE purchase prices. However, after their vehicles are purchased, EV buyers can receive as much as $7,500 in nonrefundable federal tax credit, when they file their income tax returns. Note that on January 1, 2019, Tesla became the first EV manufacturer to have their tax credit decrease. After 200,000 EVs from a given EV manufacturer are sold, the tax credit for any more EVs from that manufacturer must decrease, according to the IRS. In some states, like California, EV buyers can also receive an additional $2,500 tax rebate. These incentives will reduce the purchase price of an EV considerably, making the price of an EV very competitive with the price of an ICE.

In considering the price of an EV, it is important to consider the cost of running the vehicle. EVs cost less to run than ICEs for several reasons. First, using electricity as a source of energy is cheaper than using gas as a source of energy. We have included a calculation in the appendix showing that the difference in average MSRP costs for owning an EV will be recouped after about 5.2 years, just by using electricity instead of gas for fuel. Since the average U.S. customer holds onto their car for 6.5 years, an average EV cost will actually be just about equal to or even less than the cost of an ICE, when the costs for running the vehicle are considered. This does not even include the savings in incentives one gets for buying an EV, which we mentioned above. Another reason why EVs are cheaper to run is that EVs are less costly to maintain, because they are simpler machines with less moving parts. Lastly, the higher efficiency of the EV motor and its ability to use regenerative braking leads to better fuel economy. Thus, the overall price of an average EV is actually lower than...

Produkt-Details

• Erscheint lt. Verlag: 18.2.2021
• Sprache: englisch
• Themenwelt: Technik ► Fahrzeugbau / Schiffbau
• ISBN-10: 1-7334755-2-4 / 1733475524
• ISBN-13: 978-1-7334755-2-5 / 9781733475525