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Buyers of electric vehicles (EVs) may be very disappointed

- September 22, 2011

Behind the electric vehicle (EV) hype there are a number of sticky issues that have yet to be overcome: If they’re not, consumers may be mightily disappointed.
In response to our August feature, “Build an electric vehicle from the ground up,” which focused on John Santini’s personal EV project, one reader took some time to point to some inconvenient questions that still need answering, assuming lithium technology is not a factor:

1: Expected mileage (not the bloated advertised mileage) between charges
a: Night driving with headlights, parking lights being used.
b: Winter driving requiring heat for the occupants.
c: Summer driving requiring air conditioning for the occupants as well as the battery.
d: Accessories such as radio and windshield wipers, air moving motors.
e: Hills and grades for most parts of the country.

2: Charging time versus charging current
a: Compromise between the greater the charging current and life reduction.
b: Capacity reduction due to cell unbalances.

3: Finally the results of battery aging
a: Increasing charge/discharge cycles will reduce capacity.
b: Battery “calendar” life from manufacture to current time. This is rather unknown with other battery types.
c: Cell balancing to assure maximum energy storage.
d: Life reduction due to extremes of battery temperature.
Many of the above items were applicable to lead-acid batteries used in past electric vehicles (for a previous electric vehicle) the advertised life of “up to 75 miles” resulted in an actual range of less than 5 miles of driving distance.

In all probability current electric vehicles will have an actual expected range of 10% (or less) of the advertised life.

For the uninformed consumer who obtains an electric vehicle, he will be very disappointed in a few years, especially if he is not informed of the above limitations.

The current hybrid Toyota (using nickel metal hydride batteries) has/had a range of about four miles when not allowed to automatically switch to the gasoline engine.

Any comments?

He was actually looking for comments from me, but I’m doubting the viability of EVs myself, now that he’s pointed out these little issues.

So, what do you think? Have these challenges been addressed?

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