Posted by Neo on January 16, 2010, 9:22 am
Li-ion and Li-FE batteries can only sustain a limited number of full-
discharges
before they die. To extend the life of Li-ion and Li-FE(PO4) batteries
a computer
monitor is used to prevent the battery cells from fully discharging
and start to
recharge the battery at an earlier time. The reports I've read seems
to suggest
that the earlier the recharging occurs the longer the battery will
live - but this
means only using a fraction of the available power of the battery
system -
so there is this trade off between the lifespan of the battery and the
range of
the BEV. Engineering tricks to extend the range with a limited
battery power
includes installing a huge battery pack (BYDs e6), decreasing the
payload
of the vehicle (Tesla Roadster), making the BEV very light and
aerodynamic
(Aptera 2e), having an onboard ICE electric generator(chevy Volt),
reducing
the range (Toyota PHEV prius), reducing the lifespan of the battery,
or
a compromise of all the above (Nissan Leaf). Other things that
extend
or diminsh the lifespan of the battery (and effect the charge it can
ultimately
hold) is the operating temperature of the battery when it is under
load.
To maximize the battery power of the Tesla Roadster, Tesla motors uses
a battery anti-freeze/liquid coolant system to prevent the batteries
from
overheating when under high electric load. Currently the Toyota Prius
and the Honda Insight HEV only air cool their NiCad Battery packs.
The battery has an optimum temperature range - when the temperature
is too high the battery ages prematurely and when the temperature is
too
low the battery maximum load (SOC) diminishes.
> > Maybe cheaper, but not free. The smaller the vehicle, the cheaper it should
> > be, if mainstream technology.
> > Have you considered the extra food you would eat to maintain your body
> > weight and the medical bills from the extra wear and tear on your body from
> > exposing yourself to UV and vehicular traffic?
> > harry wrote:
> > Batteries packs for the scooter I'm looking at are $85.00, hardly a
> > major expense. With two battery packs the charge times are not much an
> > issue foe me either, considering I drive less than five miles a day.
> > On 6 Jan, 13:08, nos...@nevis.com wrote:
> > The point is once it's paid for, other than regular maintenance, yes it
> > is free. No gas, no road tax, batteries charged by existing PV. BTW
> > battery packs are under $00.00, the equivalent of two tanks of gas in
> > Canada.
> > Josepi wrote:
> > You totally miss the point. They are not free, no matter how far you stick
> > your head up your ass.
> Some of these batteries only charge up around one hundred times. There
> is significant deterioration in their capacity as they age.
> It's one thing to charge a small battery with a PV panel when you get
> to larger ones you need very large panels costing $K. The PV panels
> deteriorate too.
> As for cars, if you travel more than twenty or thirty miles ist
> becomes impossible to recharge overnight from a standard domestic
> power outlet.- Hide quoted text -
> - Show quoted text -
Posted by Michael B on January 16, 2010, 1:27 pm
The Prius charger kicks in when the battery is at 80%.
And it has a CVT, so may not do well with hauling heavier
loads.
> Li-ion and Li-FE batteries can only sustain a limited number of full-
> discharges
> before they die.
Posted by Bruce Richmond on January 15, 2010, 3:18 am
> > So a fat guy has no gas economy on a scooter.
> > LOL
> > Neo wrote:
> > It's a matter of power to weight ratio, a 240lb scooter with
> > 10 HP is 24 lb per horsepower, my Saturn weights 2400lbs and
> > has 100 HP, the same power to weight ratio. In town a scooter would have
> > no problem keeping up with traffic, few people are going to use one for
> > anything other than short trips anyway and off major highways.
> > Which at that weight is likely no safer than a scooter or motorcycle ;~)
> I agree that a scooter is would have no problem in a
> urban driving environment - it would also have a parking
> and manueverablity advantage over the larger cars and
> trucks as well. Its disadvantage would be protection
> from the weather and safety. Certain metro-only cars
> like ones made in Inda or China (e.g. Reva, Flybo)
> might be a better fit than a scooter if weather or cargo
> capacity was a primary need/mission. If cargo capacity
> is not a problem and the operator is physically fit -
> a regular bicycle might be a better fit in an urban
> environment than a scooter.
> With a ICE vehicle the power transfer efficency is not just
> a matter of power to weight ratio but also the ICE transmission
> efficiency (power to transfer ratio). for a particular speed which
> is why very skilled drivers can optimize energy efficiency
> with a manual transmission and why a properly tuned
> transmissions with additional drive gears (or a CVT) has
> better fuel efficiency than the a vehicle with less drive
> gears. Each vehicle is designed with a maximum payload
> in addition to its curb weight which the ICE is designed
> to efficiently handle - that maximum payload includes the
> weight of the operator/driver - so a 400 lb scooter operator
> take more fuel to move than a 100 lb scooter operater
> (with no other payload) - not to mention that a skinny
> operator might have less wind resistance at higher speed.
Your ideas on the effects of weight on fuel economy need some
revision. Driving down the highway at near constant speed added
weight has almost no effect on fuel mileage. It does take more fuel
to accelerate, but much of that energy can be recovered by a hybrid
with regenerative braking.
Recently I purchased two ton of coal from a store near where I work,
11 miles from home. Rather than pay them to deliver it to my home, or
borrow a truck and make a special trip myself, I just loaded 800 lbs
into my car each day for five days. That way I figured the only cost
for transport would be the additional fuel used for my trip home as
compared to not having the coal in the car. The car happen to be a
2001 Prius that has a readout for instantaneous and average fuel
milage. It also has regenerative braking. Turned out that I got 52
mpg, about the same as I get without the extra 800 lbs. The main
difference was that acceleration was sluggish due to the extra
weight. The trip was mostly on level roads with a few gentle hills.
http://nepacrossroads.com/download/file.php?id=16495&mode=view
Before anyone gives me grief about hauling 800 lbs of coal in the car,
just think of it as four two hundred pound passengers :)
The other day I tried keeping the speed down around 40 to 50 mph for a
40 mile trip over secondary roads. The Prius averaged 60 mpg. I have
several motorcycles. The one that gets the best mileage is a 1981 GPZ
550 Kawasaki. At 55 mph it gets 55 mpg. This 1972 BMW 750 only gets
about 15 mpg
http://nepacrossroads.com/download/file.php?id=16495&mode=view
But somehow that doesn't bother me a bit :) That's me driving 66. We
took 3rd in the championship last year.
> Once the kinetic energy of the ICE moves the tires - the
> vehicle has wind resistance and the tire's friction/rolling
> resistance of the tires to deal with. The wind resistance
> is a function of wind surface and that wind's surface
> drag coefficient. Most scooters and motorcycles have
> very little wind surface but a high wind surface drag
> coefficient. Most four wheeled vehicles like trucks
> have a much larger wind surface but a lower wind
> surface drag coefficient. While one passenger/driver
> motorize bikes have the potential for the lowest overall
> wind resistance and probably the highest fuel efficiency
> that commercial potential has not been realized.
Posted by Neo on January 15, 2010, 12:55 pm
After 45mph - when driving at a constant speed 50% of all the
energy expended by a motor vehicle is used to overcome wind
resistance. Your Prius is about 3200lbs so adding 800lbs of
payload is is adding about 25% of extra weight to the Prius
which should be within its designed performance. I personally
go about 55mpg on a 2006 Prius on a long trip from Washington
DC to Grand Rapids Michigan - my mileage would have
been better if I had not sped up to 70mph in Michigan but
almost all the vehicles on the super highway in Michigan
are going at 70 to 80 mph there. However, while I was in
Maryland, Pennsylvania, and Ohio I drove about 55 mph
(I believe I could have gotten 60mph if I stuck to 55mph
all the way) .
Question: Does a motorcycle wind cowls help with either
performance or fuel efficiency? If so how much?
> > > So a fat guy has no gas economy on a scooter.
> > > LOL
> > > Neo wrote:
> > > It's a matter of power to weight ratio, a 240lb scooter with
> > > 10 HP is 24 lb per horsepower, my Saturn weights 2400lbs and
> > > has 100 HP, the same power to weight ratio. In town a scooter would have
> > > no problem keeping up with traffic, few people are going to use one for
> > > anything other than short trips anyway and off major highways.
> > > Which at that weight is likely no safer than a scooter or motorcycle ;~)
> > I agree that a scooter is would have no problem in a
> > urban driving environment - it would also have a parking
> > and manueverablity advantage over the larger cars and
> > trucks as well. Its disadvantage would be protection
> > from the weather and safety. Certain metro-only cars
> > like ones made in Inda or China (e.g. Reva, Flybo)
> > might be a better fit than a scooter if weather or cargo
> > capacity was a primary need/mission. If cargo capacity
> > is not a problem and the operator is physically fit -
> > a regular bicycle might be a better fit in an urban
> > environment than a scooter.
> > With a ICE vehicle the power transfer efficency is not just
> > a matter of power to weight ratio but also the ICE transmission
> > efficiency (power to transfer ratio). for a particular speed which
> > is why very skilled drivers can optimize energy efficiency
> > with a manual transmission and why a properly tuned
> > transmissions with additional drive gears (or a CVT) has
> > better fuel efficiency than the a vehicle with less drive
> > gears. Each vehicle is designed with a maximum payload
> > in addition to its curb weight which the ICE is designed
> > to efficiently handle - that maximum payload includes the
> > weight of the operator/driver - so a 400 lb scooter operator
> > take more fuel to move than a 100 lb scooter operater
> > (with no other payload) - not to mention that a skinny
> > operator might have less wind resistance at higher speed.
> Your ideas on the effects of weight on fuel economy need some
> revision. Driving down the highway at near constant speed added
> weight has almost no effect on fuel mileage. It does take more fuel
> to accelerate, but much of that energy can be recovered by a hybrid
> with regenerative braking.
> Recently I purchased two ton of coal from a store near where I work,
> 11 miles from home. Rather than pay them to deliver it to my home, or
> borrow a truck and make a special trip myself, I just loaded 800 lbs
> into my car each day for five days. That way I figured the only cost
> for transport would be the additional fuel used for my trip home as
> compared to not having the coal in the car. The car happen to be a
> 2001 Prius that has a readout for instantaneous and average fuel
> milage. It also has regenerative braking. Turned out that I got 52
> mpg, about the same as I get without the extra 800 lbs. The main
> difference was that acceleration was sluggish due to the extra
> weight. The trip was mostly on level roads with a few gentle hills.
> http://nepacrossroads.com/download/file.php?id=16495&mode=view
> Before anyone gives me grief about hauling 800 lbs of coal in the car,
> just think of it as four two hundred pound passengers :)
> The other day I tried keeping the speed down around 40 to 50 mph for a
> 40 mile trip over secondary roads. The Prius averaged 60 mpg. I have
> several motorcycles. The one that gets the best mileage is a 1981 GPZ
> 550 Kawasaki. At 55 mph it gets 55 mpg. This 1972 BMW 750 only gets
> about 15 mpg
> http://nepacrossroads.com/download/file.php?id=16495&mode=view
> But somehow that doesn't bother me a bit :) That's me driving 66. We
> took 3rd in the championship last year.
> > Once the kinetic energy of the ICE moves the tires - the
> > vehicle has wind resistance and the tire's friction/rolling
> > resistance of the tires to deal with. The wind resistance
> > is a function of wind surface and that wind's surface
> > drag coefficient. Most scooters and motorcycles have
> > very little wind surface but a high wind surface drag
> > coefficient. Most four wheeled vehicles like trucks
> > have a much larger wind surface but a lower wind
> > surface drag coefficient. While one passenger/driver
> > motorize bikes have the potential for the lowest overall
> > wind resistance and probably the highest fuel efficiency
> > that commercial potential has not been realized.- Hide quoted text -
> - Show quoted text -- Hide quoted text -
> - Show quoted text -
Posted by vaughn on January 15, 2010, 10:56 pm
>Question: Does a motorcycle wind cowls help with either
>performance or fuel efficiency? If so how much?
It depends! A properly designed full faring can certainly reduce air drag and
increase performance. On the other hand, many years ago I put a handlebar
fairing with a windhield on my 1965 BMW. It noticably decreased performance,
but I kept it because it increased my comfort and seemed to help the 4-wheel
drivers spot me.
Vaughn
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> > be, if mainstream technology.
> > Have you considered the extra food you would eat to maintain your body
> > weight and the medical bills from the extra wear and tear on your body from
> > exposing yourself to UV and vehicular traffic?
> > harry wrote:
> > Batteries packs for the scooter I'm looking at are $85.00, hardly a
> > major expense. With two battery packs the charge times are not much an
> > issue foe me either, considering I drive less than five miles a day.
> > On 6 Jan, 13:08, nos...@nevis.com wrote:
> > The point is once it's paid for, other than regular maintenance, yes it
> > is free. No gas, no road tax, batteries charged by existing PV. BTW
> > battery packs are under $00.00, the equivalent of two tanks of gas in
> > Canada.
> > Josepi wrote:
> > You totally miss the point. They are not free, no matter how far you stick
> > your head up your ass.
> Some of these batteries only charge up around one hundred times. There
> is significant deterioration in their capacity as they age.
> It's one thing to charge a small battery with a PV panel when you get
> to larger ones you need very large panels costing $K. The PV panels
> deteriorate too.
> As for cars, if you travel more than twenty or thirty miles ist
> becomes impossible to recharge overnight from a standard domestic
> power outlet.- Hide quoted text -
> - Show quoted text -