Don SSDD wrote:I believe innovation in battery technology is occurring at a faster than ever pace, and in five to ten years batteries will weigh a lot less and have considerably more power.
The concept of a battery is primarily associated with chemical reactions which are able to store electrical charges. Unless there is some fantastic new chemistry invented immediately and perfected into useful manufacturing on a global scale, I don't see how in five years or even ten years that storing electric energy using chemical reactions in a storage battery will produce the predicted outcomes of "a lot less weight" and "considerably more power." The energy density per pound of various chemical reactions has already been explored for several decades. There may be improvements in manufacturing methods that produce longer service life or improved safety, but to assume there is a big breakthrough to entirely new technology only five years in the future is perhaps overly optimistic.
Don SSDD wrote:The simplicity of an electric motor as compared to petroleum with all the sensors, injectors, exhaust complexity, emissions, oil changes...
The actual electric motor is rather simplified compared to modern internal combustion engines, and the electric motor has only one moving part. But the assumption that there is overall simplification is not justified. The electric motors are generally permanent-magnet alternating-current (PMAC) motors, and they are powered by a battery that delivers just a constant direct current and voltage. In between the battery and the motor there must be very sophisticated electronics that modulate and regulate the direct current into complex alternating current waveforms in order to control the electric motor speed and direction of rotation. These electronic drive assemblies are just one part of the electronics needed.
Generally the electric motor does not directly drive the axles, so an intervening gear case or transmission is needed.
To control modern batteries, the batteries themselves contain electronics which must monitor the individual cells for voltage and temperature, and prevent the battery from being damaged if certain conditions exist, either caused by the load on the battery or the charging current applied to the battery. Also the battery temperature needs to be regulated and may need cooling or heating.
The batteries must be continually recharged. The source of the electrical energy to recharge the battery must be compatible with the battery, so that means a direct current of suitable voltage and with proper current limiting. To create such a source of recharging requires that regular home AC power at either 120 or 240 Volts must be converted into the proper DC voltage and current. These recharging convertors are part of the overall system of the "electric motor" in a vehicle of any kind and are on the vehicle.
In the case of automobiles, there is the possibility to generate electrical power during deceleration, a process known as regenerative braking. In order for this to occur there must be some sort of controller that switches modes so the motor can become a generator and battery can become a load.
Looking at the total system we see there are really several components, and not just a simple electric motor:
--a battery with its own electronic protection system
--a motor drive electronics assembly to create the AC polyphase drive signals
--a multi-phase winding PMAC motor
--a mechanical gear case
--a regenerative braking module
--a re-charging module
At every stage of the conversion of energy to a new form from another form, the process is not perfectly efficient and some energy is lost in the form of heat. For this reason all of the above need cooling (or perhaps heating in very cold temperatures) to remain at a suitable working temperature. This adds another electric motor to pump cooling fluid. There may be more than one cooling system as each component needs a particular sort of fluid for lubrication. Each cooling system needs an electric motor to move the fluid.
The application to boats is a bit unique because boats are usually only operated in a narrow range of temperatures, and the motor can be cooled by being immersed into the seawater.
In automobiles the passenger compartment requires cooling or heating. For cooling, a compressor for air conditioning must be driven by an electric motor. For heating, an electric heating element will need to be controlled and a fan motor must be operated.
Also, all the usual 12-Volt DC items on a vehicle like lamps, displays, radios, door locks, power window motors, must have power, so another electronic module is needed to convert the main battery (usually about 400 to 500-Volts) power down to 12-Volt power. This module may also need cooling. Usually there is also a 12-Volt battery, and it needs charging.
I don't really see the electric vehicle as being substantially simpler than the internal combustion vehicle. The manufacturing of internal combustion engines has been improved over more than a century to the point where a vehicle's engine is not usually a big source of failure.
As for service, the battery itself is now a service item with an upper bound of possible re-charge cycles and with a ever decreasing energy storage capacity with each discharge-charge cycle. At least one electric vehicle (EV) manufacturer specifies that the undercarriage of the car must be washed at certain intervals if used in snowy regions that apply salt to the roads. And lubricating and cooling fluid levels must be checked and also be changed at intervals. Adding fluid or changing fluid is much more complicated that changing the oil in an internal combustion engine or in an automatic transmission.
I doubt that all the rather high-voltage and high-power electronic modules will have an infinite lifespan, and they are going to cost a lot more to replace than four or six spark plugs or a small engine spark control module. The electrical harnesses, particularly the main harness carrying the 400 or 500 AC and DC waveforms, could also be service items, and they will be more expensive than fan belts or water hoses.
To get a better sense of the overall complexity of an electric vehicle (EV), I recommend you watch this 40-minute presentation by Professor John D. Kelly. Professor Kelly tears down a Chevy BOLT. The Chevy BOLT is the highest rated EV in Consumer's Reports recent analysis. The presentation examines in detail the many systems associated with an EV. Watch at
https://www.youtube.com/watch?v=r37nqfnV9EUBy the way, when I say "tears down" I do not mean that in a derogatory sense. Professor Kelly offers much praise for the BOLT and admits he was sufficiently impressed to buy one .
Don SSDD wrote:...[electric motor propulsion] will be very attractive once the range is extended and the recharging time is reduced to acceptable numbers.
Reduction in re-charing time is already possible with the direct DC charge method, also called LEVEL 3 FAST CHARGING. There are commercial grade Level 3 charging stations that deliver re-charging current at around 500-Volt DC to a special optional module in the vehicle (and here again we add more complexity to the vehicle) called a direct-DC-charge regulator that regulates the charging to suit the battery. Such re-charging stations at present cost about $10,000 to $15,000. Since they use very high amounts of energy, they must be powered by 240-VAC power with similarly high capacity. Having one of these in your garage at your home is unlikely for most people due to the cost of the device itself, the cost of the installation, and load it creates on the home electrical system. The optional direct-DC-charge module may add another $700 to $1,000 to the vehicle price.
For more about re-charging stations at LEVEL 1, LEVEL 2, and LEVEL 3, see
http://www.evtown.org/about-ev-town/ev- ... evels.htmlThe overall goal of reducing dependence on electricity generated by fossil fuel is not provided in these vehicles themselves. They don't operate of photovoltaic self-generated power. For most of them, the energy they will run on will come from fossil-fuel generated utility power. Creation of mass-scale power generation with renewable methods is still a long way off.