Update to EV Batteries
Gordon K. Glatz
October 01, 2007
I received an email from a reader who owned and drove an EV. He explained that the high cost of the battery pack was due to the fact that the car took 50 batteries. If he read my bio he would know I am a retired master electrician, and have taught electrical classes. I do not write before I check on what I am writing about, and the only applications where that kind of voltage is required is where they are trying to get high performance. Such as 0 to 60 in a few seconds and or higher speeds, as with the Tzero, and some other EV's that are built for racing or record runs. Most of these are AC systems using High Voltage 3 phase Motors, although some have been built using higher voltage DC motors. This is over kill for a general consumer car, and increases the number of batteries required. It is also more of a danger to the home repairman then a lower voltage system.
Now I don't know about you, but I was always able to repair my own car. I never took any car of mine to a garage. In earlier years the cars had plenty of room under the hood to work. I can remember when I could sit on the fender with my feet down beside the engine, you try that with todays ICE cars. An EV with the exception of the batteries, especial a DC one returns to the room of that day. I would imagine that present mechanics would not like this, as the more complex the ICE car became the less the private individual could do his own repairs. In later years I could not afford to pay the high cost of those repairs, and had developed an allergy to something that made me sick when I tried to work on a car. So I either had to rely on my son to make the repair, (if he could handle it) or get a another car. So I would be glad to see the return of a vehicle that we could repair are selves.
It has been shown that the average person drives around 30 miles a day, mostly back and forth to work or around town, to do their shopping or for entertainment. They drive in town at no more then 35 to 45 mph and on most free ways at no more then 55 to 65 mph. Most of the small one to four passenger cars that have been produced here or in other countries have been of this type. Even the conversions of regular name brand ICE cars have been of this type. Usually using a DC motor and no more then 20 batteries.
Of the two ways of going about this AC or DC, I am more for using the DC system then AC, because it is much cheaper, simpler to build, and maintain. AC requires a cooling system for the 3 phase motor, and a convertor to change the batteries output from DC to AC. Most of the applications using DC motors that I have seen and read about were air cooled and required no heat sinks. The batteries were the same average size Lead Acid ones as used for starter batteries in an ICE car, or the Optima Red or Yellow Top ones. People who are interested in going green to get rid of the gas pump, for the most part do not understand these differences. EV's can be built with out the need for certain systems used in the ICE cars. Such as the cooling, ignition, and exhaust systems, which all add to the total cost of the vehicle.
On further correspondence I find he is quite knowledgeable on AC-EV systems, and the car he drives is a USElectricar, a conversion of a Geo Prizm. These vehicles were factory-converted with a Dolphin controller and a Hughes 3-phase AC electric motor. It is a 300 volt system, using two banks of 25 batteries hooked in series parallel and the motor requires cooling. The cost is high because you have to add the price of the base car, plus the conversion, and of course the profit for the company.
The home converter either already owns the car, or buys one that has a burnt out ICE engine for junk, and does the conversion their self using a DC kit from one of the suppliers. This can result in an EV for less then the cost of a new ICE car. It is not an easy job for one who knows little about mechanics, but can be done if they are willing to learn.
When I worked at Disney at first they used Ford products, then later changed over to GM. My section had a ford pickup which we plugged in right out side the door. I drove that truck many times, and my supervisor drove it many times into Orlando on I-4 at speeds of 55 - 60 mph. He made the round trip with out recharging until he returned, and never got stranded. Now I don't know what the specifications for motor and batteries were used in that truck, but I know it did not use more then 20 batteries.
Which proves that all electrics can be built NOW at a reasonable cost, and with range enough for the average consumer.
Copyright October 2007 by Gordon K. Glatz
Now I don't know about you, but I was always able to repair my own car. I never took any car of mine to a garage. In earlier years the cars had plenty of room under the hood to work. I can remember when I could sit on the fender with my feet down beside the engine, you try that with todays ICE cars. An EV with the exception of the batteries, especial a DC one returns to the room of that day. I would imagine that present mechanics would not like this, as the more complex the ICE car became the less the private individual could do his own repairs. In later years I could not afford to pay the high cost of those repairs, and had developed an allergy to something that made me sick when I tried to work on a car. So I either had to rely on my son to make the repair, (if he could handle it) or get a another car. So I would be glad to see the return of a vehicle that we could repair are selves.
It has been shown that the average person drives around 30 miles a day, mostly back and forth to work or around town, to do their shopping or for entertainment. They drive in town at no more then 35 to 45 mph and on most free ways at no more then 55 to 65 mph. Most of the small one to four passenger cars that have been produced here or in other countries have been of this type. Even the conversions of regular name brand ICE cars have been of this type. Usually using a DC motor and no more then 20 batteries.
Of the two ways of going about this AC or DC, I am more for using the DC system then AC, because it is much cheaper, simpler to build, and maintain. AC requires a cooling system for the 3 phase motor, and a convertor to change the batteries output from DC to AC. Most of the applications using DC motors that I have seen and read about were air cooled and required no heat sinks. The batteries were the same average size Lead Acid ones as used for starter batteries in an ICE car, or the Optima Red or Yellow Top ones. People who are interested in going green to get rid of the gas pump, for the most part do not understand these differences. EV's can be built with out the need for certain systems used in the ICE cars. Such as the cooling, ignition, and exhaust systems, which all add to the total cost of the vehicle.
On further correspondence I find he is quite knowledgeable on AC-EV systems, and the car he drives is a USElectricar, a conversion of a Geo Prizm. These vehicles were factory-converted with a Dolphin controller and a Hughes 3-phase AC electric motor. It is a 300 volt system, using two banks of 25 batteries hooked in series parallel and the motor requires cooling. The cost is high because you have to add the price of the base car, plus the conversion, and of course the profit for the company.
The home converter either already owns the car, or buys one that has a burnt out ICE engine for junk, and does the conversion their self using a DC kit from one of the suppliers. This can result in an EV for less then the cost of a new ICE car. It is not an easy job for one who knows little about mechanics, but can be done if they are willing to learn.
When I worked at Disney at first they used Ford products, then later changed over to GM. My section had a ford pickup which we plugged in right out side the door. I drove that truck many times, and my supervisor drove it many times into Orlando on I-4 at speeds of 55 - 60 mph. He made the round trip with out recharging until he returned, and never got stranded. Now I don't know what the specifications for motor and batteries were used in that truck, but I know it did not use more then 20 batteries.
Which proves that all electrics can be built NOW at a reasonable cost, and with range enough for the average consumer.
Copyright October 2007 by Gordon K. Glatz
Print
Email
