It does appear that the EV vehicles are able to be charged by Level 1, 2 or 3 charging stations. From the writers understanding Level 1 is a low rate, long charge time that is more of a backup when Level 2 or 3 are not available. In the EV that I test drove it was simply a 120Vac extension cord that had to be plugged to 120Vac circuit outlet protected by 20 amp circuit breaker. The vehicle had a 50 foot cord and was stored in trunk. The low rate charger was part of the vehicle.
In the test program in which I participated a Level 2 charger was installed in my garage and was powered by 240 Vac plus a neutral connection. Part of this garage installation was a recording wattmeter that measured the kWh taken during recharge---handy. Again the AC to DC conversion was in the charging circuit that was part of the cars electronics. The kWh rating of the vehicle pack was 22.6 kWh and the charging system required about 5 hours to completely recharge a fully discharged battery. The test vehicle could not be recharged by a Level 3 charger.
If we look at say the Nissan Leaf for example it can be had with one input connection that will allow Level 1 and 2, and a second input connection for level 3. The car comes equipped with a 120Vac cord some 50 feet long and with a connector attached to mate with keyed Level 1, 2 connection. In the case for Level 1 operation the plug must be connected to a 120Vac outlet with at least 20amps available and protected by a 30 amp circuit breaker. For Level 2 operation, a charger such as a Leviton, mounted on say the garage wall, draws 240Vac from the house wiring through 2, 50 amps ganged circuit breakers. The output line from the Leviton charger is 18’ long and terminated into the matching Level 1, 2 connector mounted on the car. Note so far that the Level 1 charging cord (120Vac) and the Level 2 output from the Leviton charger plug into the same connection mounted on the Nissan Leaf. Note there are several different models of the Leviton chargers that can perform Level 2 charging for the Leaf differing mainly in the amount of amps they can provide from the 240 Vac house source. A note: installation of the Leviton charger or equivalent is easy IF you have a pair of spare circuit breaker positions left in your current box. As happened in my case I did not, so a small sub panel had to be mounted to house these breakers--- PITA.
COMMENT------Leviton is only one company sizing up the market for Level 2 home chargers. Actually they are NOT only for home. In some states, California for example, clusters of Level 2 chargers, where 6 to 10 are mounted on an island at a charging station that may have 1 or 2 level 3 charging positions. So far Level 3 charging stations are supervised i.e. not unmanned or unattended.
LEVEL 3 CHARGING STATION: This charger produces DC up to 500 Vdc and amperage up to 125 amps DC. They are powered typically from a 480 Vac, 3-phase. This in most states is called a Commercial 1 service and usually rated 480/277, 3 phase, 400 amps-Y connected. The electronics that control the charging curve for the car battery are on board the car. So far as I know everyone using Li-ion cells are using CCVV charging i.e. constant current, variable voltage. In this manner the car designer controls the charging rate and tapers the current rate as the cell approach the upper voltage limit. BTW the Li-ion is a wonderful cell but big or small they cannot tolerate over-voltage OR under-voltage without degrading the life of the pack. Since most car manufacturers are stressing 150,000 mile life they DO pay a great deal of attention to over/under voltage AND balance.
HOW WILL YOU PAY FOR THIS? ---Much is made of the fact that charging cost can all go on your credit card automatically. But from what I can read what you will pay for is connection time for so many hours (fractions of hours). For example a Level 3 connection will cost $12/ hour. Level 2 will be about $6/ hour and if 2 cars connect it may be $10/hour for both cars. Mention was made that Level 3 will be terminated at 90% of FC, full charge. This will be done by measuring the charging current drawn the CCVV charger. Note at $0.14/kWh, $12.00 pays for 86 kWh. So only on trips will the Level 3 charging see much use. A more likely situation will be when the driver is at motels, restaurants and shopping centers where the driver will buy a length of time i.e. almost like a parking meter. People knowing their cars will likely buy enough energy to get them to get them back to their garage where they will connect to their Level 2 charger to get ready for the next drive. IT IS EVOLVING.
INTERESTING-----
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