Electric/hybrid question

[nothermark]

Just asking in case some folks here have a clue. i don't kow if there
is a "correct" group. Since cars like the Subaru have a lot of owners
who expect high service life I'm wondering about hybrid batteries. Has
anyone seen anything on how long the battery packs last? or what
replacement costs will be?

 

[mark jb]

Just asking in case some folks here have a clue. i don't kow if there

is a "correct" group. Since cars like the Subaru have a lot of owners
who expect high service life I'm wondering about hybrid batteries. Has
anyone seen anything on how long the battery packs last? or what
replacement costs will be?

As far as I can tell, basically what you save on petrol will be spent on
battery packs.
At least several thousand dollars, going on the UPS battery prices I've
seen. (Banks of 2v/40ah or similar)

-mark

 

[Ed P]

Just asking in case some folks here have a clue. i don't kow if there
is a "correct" group. Since cars like the Subaru have a lot of owners
who expect high service life I'm wondering about hybrid batteries. Has
anyone seen anything on how long the battery packs last? or what
replacement costs will be?

I own a '04 Toyota Prius with 37k miles and follow a couple of Prius
chat groups. First, the Prius has 2 batteries: a high voltage traction
battery and a 12 volt lead-acid battery, that is small compared to the
typical car.

Toyota projects the traction battery to live the life of the car. The
car's computer software is biased to optimize battery life, wherein the
traction battery "operates" in the range of about 40% to 80% state of
charge. While there has been specualation that a new traction battery
would presently cost in the order of $3000, the projection is that
prices will come down and/or market will develop for supporting battery
repair/maintenance. The traction battery contains a number of
individual cells which can be replaced individually or rejuvenated.
There will also be batteries available from wrecks. So should a
replacement battery be needed, what might actually happen is that an
exchange for a reconditioned battery might be the typcial procedure.
In the Prius, the traction battery is warranted for either 8 years/100k
miles or 10 years/150k miles, depending on the emission warranty
requirements of the state where the vehicle is sold (I hope I got this
right).

The 12 volt battery is something of a different story as it is possible
to run it completely down if one doesn't understand and allow for the
way the car works. For example, operating accessories such as the radio
when the vehicle is NOT in READY mode. Running the 12 volt battery down
is abuse of the battery and will shorten its life.

Frankly, as an owner, I worry more about failure of one of the many
computers, sensors, or the Multifunction Display out of warranty then I
do of the battery. I bought the factory extended warranty for this
reason and will have to decide whether to sell the car when the warranty
is over rather than take the risk myself.

Incidentally, my wife is averaging in the mid-50s mpg with a 90 mile
round trip commute in heavy surburban Washington, DC traffic. I am a
large person and find my '96 Outback to be more comfortable and the
Prius has peculiar visibility out of the split rear window, but in
general the Prius is a marvelous car.

Ed P

 

[Al]

Just asking in case some folks here have a clue. i don't kow if there
is a "correct" group. Since cars like the Subaru have a lot of owners
who expect high service life I'm wondering about hybrid batteries. Has
anyone seen anything on how long the battery packs last? or what
replacement costs will be?

As far as I can tell, basically what you save on petrol will be spent on
battery packs.
At least several thousand dollars, going on the UPS battery prices I've
seen. (Banks of 2v/40ah or similar)

-mark
[/QUOTE]

Yes, it's a zero sum game. But supposedly there will be fewer pollutants.

But, the auto crash rescue teams are starting to get worrried. Why?

600V for the battery pack filled with acid. What happens when that
cracks open in a crash? Do you want to pull someone out of a car that
might have 600V on the frame? Will the sparking ignite any spilled fuel?
And can you use water to douse any flames that do occur?

I haven't seen anyone address those questions except for the rescue
workers.

Al

 

[Frank Logullo]

Just asking in case some folks here have a clue. i don't kow if there
is a "correct" group. Since cars like the Subaru have a lot of owners
who expect high service life I'm wondering about hybrid batteries. Has
anyone seen anything on how long the battery packs last? or what
replacement costs will be?

I googled this up a while back. Aussie site figured battery replacement in
Prius would be $7,000.
Toyota warranty, I believe is 7/70,000 except in California where it is
10/100,000.
To me, this means, when warranty is over and batteries go, you junk the
car - not something us Subie fans would want to do.
Frank

 

[mark jb]

Yes, it's a zero sum game. But supposedly there will be fewer pollutants.

But, the auto crash rescue teams are starting to get worrried. Why?

600V for the battery pack filled with acid. What happens when that
cracks open in a crash? Do you want to pull someone out of a car that
might have 600V on the frame? Will the sparking ignite any spilled fuel?
And can you use water to douse any flames that do occur?

I haven't seen anyone address those questions except for the rescue
workers.

That's why the cables are painted a nice fluoro, UV-reacting,
glow-in-the-dark paint.
Local firies are starting to buy massive grounding straps and stakes,
grounding the car frame to earth just in case.

I've played with LV before (<1000v) and it's really quite easy to avoid
death in a simple rubber suit.

-mark

 

[nothermark]

I own a '04 Toyota Prius with 37k miles and follow a couple of Prius
chat groups. First, the Prius has 2 batteries: a high voltage traction
battery and a 12 volt lead-acid battery, that is small compared to the
typical car.

Toyota projects the traction battery to live the life of the car. The
car's computer software is biased to optimize battery life, wherein the
traction battery "operates" in the range of about 40% to 80% state of
charge. While there has been specualation that a new traction battery
would presently cost in the order of $3000, the projection is that
prices will come down and/or market will develop for supporting battery
repair/maintenance. The traction battery contains a number of
individual cells which can be replaced individually or rejuvenated.
There will also be batteries available from wrecks. So should a
replacement battery be needed, what might actually happen is that an
exchange for a reconditioned battery might be the typcial procedure.
In the Prius, the traction battery is warranted for either 8 years/100k
miles or 10 years/150k miles, depending on the emission warranty
requirements of the state where the vehicle is sold (I hope I got this
right).

The 12 volt battery is something of a different story as it is possible
to run it completely down if one doesn't understand and allow for the
way the car works. For example, operating accessories such as the radio
when the vehicle is NOT in READY mode. Running the 12 volt battery down
is abuse of the battery and will shorten its life.

Frankly, as an owner, I worry more about failure of one of the many
computers, sensors, or the Multifunction Display out of warranty then I
do of the battery. I bought the factory extended warranty for this
reason and will have to decide whether to sell the car when the warranty
is over rather than take the risk myself.

Incidentally, my wife is averaging in the mid-50s mpg with a 90 mile
round trip commute in heavy surburban Washington, DC traffic. I am a
large person and find my '96 Outback to be more comfortable and the
Prius has peculiar visibility out of the split rear window, but in
general the Prius is a marvelous car.

Ed P

thanks to all. I have seen the battery pack from the Toyota's. It
reminded me of an insutrial circuit breaker panel. One can replace
individual cells. A bad one should be relativly easy to find with a
voltmeter.

A couple of things concern me. From what I can see the hybrid uses
the battery pack/motor to average out power demands by peaking off the
battery pack. That lets the fuel engine run in a more efficient
manner but won't help under continuous heavy loads like pulling a
trailer or stop and go traffic. You do get some recovery on braking
but I don't know how significant that is. On the other side battery
technology in use so far is mature technology. I see a lot of
predictions prices will drop but I suspect they will stay the same or
increase due to hard to get materials and/or deposits to ensure
recycling of what is essentially reusable toxic waste. If I was not
looking for high milage I would be interested but I am looking at a
200,000 mi life, not 100,000 as I seem to be averaging around
30,000/yr for work. It will be interesting to watch this for the
next few years...

;-)

 

[l.lichtman]

Stop and go traffic is where the hybrid/regenerative system has the
GREATEST benefit. The car actually gets BETTER gas mileage in town
than on the freeway, for three reasons: while other cars are idling in
traffic, the Prius uses no gasoline--the engine is OFF. Every time the
brakes are applied, power is sent to the traction battery, instead of
going up as heat in the brakes. The engine starts only when the power
is needed to recharge the battery, and the computer arranges for it to
run at its most efficient operating point.

An aside: since the brakes are not used very much, brake life should
be very long.

 

[Yousuf Khan]

I googled this up a while back. Aussie site figured battery replacement in
Prius would be $7,000.
Toyota warranty, I believe is 7/70,000 except in California where it is
10/100,000.
To me, this means, when warranty is over and batteries go, you junk the
car - not something us Subie fans would want to do.

It's not likely all of the battery cells will die at the same time. You
should be able to replace just the bad ones one at a time.

Yousuf Khan

 

[Frank Logullo]

It's not likely all of the battery cells will die at the same time. You
should be able to replace just the bad ones one at a time.

Yousuf Khan

I understand they are metal hydride batteries - I use such in my digital
camera - expensive but long life.
Guess it depends how assembled and how many cells. Maybe owners can
enlighten us.

While I think hybrids are important, as a retired person who does not drive
a lot and keeps cars forever, a hybrid would probably not be cost/effective
for someone like myself.

Fank

 

[YKhan]

While I think hybrids are important, as a retired person who does not drive
a lot and keeps cars forever, a hybrid would probably not be cost/effective
for someone like myself.

Or it might be extremely appropriate for you. It looks like these cars
are best suited for puttering around town rather than on the highway.
And less you use it, the less likely any of the battery cells will die.

 

[Frank Logullo]

Or it might be extremely appropriate for you. It looks like these cars
are best suited for puttering around town rather than on the highway.
And less you use it, the less likely any of the battery cells will die.

I doubt that. I have a friend that thinks cars die of old age rather than
use. He's probably partially right, e.g. hoses, belts and tires will rot
with time, even though not used. Also my metal hydride camera batteries
lose charge when not used. I think when they are new, they lose as much as
1% per day. Hoses and belts, I can afford but batteries such as these?

I may have a hybrid one day, but I'll wait until they are time tested and
prices become competitive. Much better are diesels.
Newer ones are apparently much quieter, low sulfur fuel is in the making,
and city mileage is equivalent to highway mileage and much better than gas
engines. BTW I got a close look at a Prius the other day. Parked next to
my Forester it appeared very small. I also thought it was ugly
Frank

 

[Ed P]

I understand they are metal hydride batteries - I use such in my digital
camera - expensive but long life.
Guess it depends how assembled and how many cells. Maybe owners can
enlighten us.

While I think hybrids are important, as a retired person who does not drive
a lot and keeps cars forever, a hybrid would probably not be cost/effective
for someone like myself.

Fank

There have been a number of quite technical discussions on the Prius
traction battery at (e-mail address removed). One
individual bought a salvage Prius and described what he went through
building his own traction battery charger. (Should the traction battery
ever fail or become discharged, you cannot jump start the vehicle. The
battery must be recharged by a special system that Toyota dealers have
or replaced.) Another individual discussed taking a traction battery
apart and the procedure for rejuvenating/reconditioning individual
cells. If anyone is interested in the battery technology, I would
encourage them to search the archives for this yahoo group.

With regard to a person who does not drive a lot or only drives short
trips, be advised that hybrids do not shine mpg wise under such
circumstances. They probably do as well as non-hybrids but the first
five minutes and few miles of travel for any car drags down average mpg.

Incidentally, as I mentioned in an earlier post, my major
out-of-warranty concern would be for failure of some of the high tech
features of the Prius. Supposedly, the Multi Function Display retails
for around $3000 but supposedly re-furbished ones are being used for
warranty repairs and these are costing more like $400.

Ed P
'96 Outback & '04 Prius

 

[nothermark]

Stop and go traffic is where the hybrid/regenerative system has the
GREATEST benefit. The car actually gets BETTER gas mileage in town
than on the freeway, for three reasons: while other cars are idling in
traffic, the Prius uses no gasoline--the engine is OFF. Every time the
brakes are applied, power is sent to the traction battery, instead of
going up as heat in the brakes. The engine starts only when the power
is needed to recharge the battery, and the computer arranges for it to
run at its most efficient operating point.

An aside: since the brakes are not used very much, brake life should
be very long.

I get your point. Here is what concerns me. 1 Horsepower is 746
watts at 100% efficiency. I'm getting the idea that the battery is
around 330 V so current =watts/volts. The comes out to about 2.25
Amps/horsepower. A 40 A/hr cell has been referred to and it sounds
reasonable from what I have seen. If I assume a 10 hp traction motor
that 22.5 A under load so that cell is going flat in under 30 minutes.
Assuming the 20 - 80% charge range mentioned in another note further
reduces amount of power stored thus reducing the cycleing time of the
motor. If I then factor in that I am really pulling a 100+ hp gas
engine out and replacing it with an electric traction motor and I
wonder just how big that electric motor really is or how short the
charge capacity of the battery really is. It seems that the charging
system should hardly ever shut off. That also tosses in the issue of
how much ewear and tear on the charging motor from all the stopping
and starting. I could get more complex but I think this is enough to
show why I am wondering if hybrid technology is really that good an
idea. Fuel cells would be an entirely different picture.

FWIW: Cell replacement. I would expect a couple of cells to fail
prematurely due to manufaturing inconsistency. I would expect most of
the cells to fail together. Basically for the same reasons that large
buildings replace all the lamp bulbs at once. Life is pretty
consistent with a particular usage pattern.

 

[Here and There]

I get your point. Here is what concerns me. 1 Horsepower is 746
watts at 100% efficiency. I'm getting the idea that the battery is
around 330 V so current =watts/volts. The comes out to about 2.25
Amps/horsepower. A 40 A/hr cell has been referred to and it sounds
reasonable from what I have seen. If I assume a 10 hp traction motor
that 22.5 A under load so that cell is going flat in under 30 minutes.
Assuming the 20 - 80% charge range mentioned in another note further
reduces amount of power stored thus reducing the cycleing time of the
motor. If I then factor in that I am really pulling a 100+ hp gas
engine out and replacing it with an electric traction motor and I
wonder just how big that electric motor really is or how short the
charge capacity of the battery really is. It seems that the charging
system should hardly ever shut off. That also tosses in the issue of
how much ewear and tear on the charging motor from all the stopping
and starting. I could get more complex but I think this is enough to
show why I am wondering if hybrid technology is really that good an
idea. Fuel cells would be an entirely different picture.

FWIW: Cell replacement. I would expect a couple of cells to fail
prematurely due to manufaturing inconsistency. I would expect most of
the cells to fail together. Basically for the same reasons that large
buildings replace all the lamp bulbs at once. Life is pretty
consistent with a particular usage pattern.

http://avt.inel.gov/pdf/hev/prius2004hevamerica.pdf

The Prius has a 202V 6.5Ah battery with a 500V 50kW (67hp)
electric motor and a 76hp gas motor.

 

[YKhan]

I doubt that. I have a friend that thinks cars die of old age rather than
use. He's probably partially right, e.g. hoses, belts and tires will rot
with time, even though not used. Also my metal hydride camera batteries
lose charge when not used. I think when they are new, they lose as much as
1% per day. Hoses and belts, I can afford but batteries such as these?

How little use are you planning on not giving it? I mean for a car to
be not used and have things fail because of rot would require years in
most cases. Old age, together with heavy usage will rot things much
faster.

As for the batteries losing charge, it really doesn't matter, you still
have a gasoline motor there, it's not like as if you'll be stranded
when the batteries are fully discharged. The gas motor will recharge
the batteries while you drive. The only problem you're going to have is
that your initial gas mileage won't be nearly as good as when the car
is fully charged up. Besides, it looks like these manufacturers have a
broad definition of what a fully charged battery is. As one other
poster said about the Toyota Prius, the computer tries to keep the
battery between 40-80% full before trying to recharge it. So even a 40%
charge is considered a full charge for their purposes. I'm sure quite a
few cells could become disfunctional and you could still maintain at
least a 40% charge.

Plus another thing you have to think about is that they're only ever
trying to fill up to 80% of its maximum capacity before they stop
charging it. In a digital camera or any other consumer electronics
device, the batteries are usually taken up close to the 100% mark. The
close to the top of the line it's at, the more it leaks out, much like
a spring that's been stretched to its maximum for too long, it never
goes back to its original shape.

I may have a hybrid one day, but I'll wait until they are time tested and
prices become competitive. Much better are diesels.
Newer ones are apparently much quieter, low sulfur fuel is in the making,
and city mileage is equivalent to highway mileage and much better than gas
engines. BTW I got a close look at a Prius the other day. Parked next to
my Forester it appeared very small. I also thought it was ugly

If you think that's small, then check this out:

http://www.smart.com/

These cars have gotten extremely popular up here in Canada. It's made
by DaimlerChrysler. They're economical, and cute as a button.

Yousuf Khan

 

[YKhan]

I get your point. Here is what concerns me. 1 Horsepower is 746
watts at 100% efficiency. I'm getting the idea that the battery is
around 330 V so current =watts/volts. The comes out to about 2.25
Amps/horsepower. A 40 A/hr cell has been referred to and it sounds
reasonable from what I have seen. If I assume a 10 hp traction motor
that 22.5 A under load so that cell is going flat in under 30 minutes.
Assuming the 20 - 80% charge range mentioned in another note further
reduces amount of power stored thus reducing the cycleing time of the
motor. If I then factor in that I am really pulling a 100+ hp gas
engine out and replacing it with an electric traction motor and I
wonder just how big that electric motor really is or how short the
charge capacity of the battery really is. It seems that the charging
system should hardly ever shut off. That also tosses in the issue of
how much ewear and tear on the charging motor from all the stopping
and starting. I could get more complex but I think this is enough to
show why I am wondering if hybrid technology is really that good an
idea. Fuel cells would be an entirely different picture.

You gotta remember, the savings you get from electric motors is as a
result of essentially zero energy expenditure during idle situations.
When you're in stop'n'go city traffic (assuming you're not using
electricity for other purposes like listening to the radio or running
your A/C, but even still the energy draw should be pretty miniscule),
the car uses zero watts when it's stopped. A gas car that is stopped
has to keep its gas motor running for the moment it's gotta getting
going again, not so with an electric motor.

When at high speed, the electric motor is probably hardly being used,
it's the gas motor doing all of the work. So the electric batteries are
being recharged during high speed life. At most, I think the electric
motors might kick in at speed when attempting to accelerate, so that
the gas motor will get a bit of an assist.

Yousuf Khan

 

[Ed P]

As for the batteries losing charge, it really doesn't matter, you still
have a gasoline motor there, it's not like as if you'll be stranded
when the batteries are fully discharged. The gas motor will recharge
the batteries while you drive. The only problem you're going to have is
that your initial gas mileage won't be nearly as good as when the car
is fully charged up.

I would suggest that you have over simplified and misunderstand the
operation of full hybrids such as the Prius. In the Prius there is no
separated alternator or starter. A small 12-volt battery provides power
to boot up the computer which in turn switches the high-voltage traction
battery into the system. To start the ICE (internal combustion engine),
the traction battery provides the power to one of the motor/generators
to spin up (start) the ICE. Dead traction battery, means NO START -=
period. I believe the biggest part of the fuel efficiency gain comes
from an integrated system of ICE and electric motor/generators that
allows for a relatively small ICE to operate in a higher efficiency mode
than in a regular car. The electric motors provide added torque when
needed to allow the use of the small, high-efficiency ICE.

Besides, it looks like these manufacturers have a

broad definition of what a fully charged battery is. As one other
poster said about the Toyota Prius, the computer tries to keep the
battery between 40-80% full before trying to recharge it. So even a 40%
charge is considered a full charge for their purposes. I'm sure quite a
few cells could become disfunctional and you could still maintain at
least a 40% charge.

Plus another thing you have to think about is that they're only ever
trying to fill up to 80% of its maximum capacity before they stop
charging it. In a digital camera or any other consumer electronics
device, the batteries are usually taken up close to the 100% mark. The
close to the top of the line it's at, the more it leaks out, much like
a spring that's been stretched to its maximum for too long, it never
goes back to its original shape.

First, it is a mis-statement to say that Toyota ever considers a 40% SOC
to be full charge. I believe there are two primary issues: The traction
battery must always be protected to have enough charge to start the ICE
and fully charging or fully discharging the traction battery has an
adverse effect on its life expectancy. Apparently, Toyota determined
that a SOC range of 40% to 80% was close to optimum for battery life.
Also, regenerative braking can only function if the battery has room to
accept the charge.

In hybrids, the most efficient operation is under power of the ICE.
There are conversion losses in using gasoline to run the ICE to charge
the battery which then drives the electric motors. On the other hand,
regenerative braking recovers energy that would otherwise be dissipated
as heat.

I think many buy the Prius in part because it is such a technological
marvel. Clearly, as demonstrated by the Honda Accord Hybrid, the hybrid
approach can be tailored to better acceleration or to best gas mileage
with reduced emissions in both cases. Of great importance is the
various hybrids now on the market demonstrate that you don't have to
give up acceptable performance to be cleaner and more fuel efficient.

Ed P
'96 Outback 99k miles
'04 Prius 37k miles

 

[Ed P]

You gotta remember, the savings you get from electric motors is as a
result of essentially zero energy expenditure during idle situations.
When you're in stop'n'go city traffic (assuming you're not using
electricity for other purposes like listening to the radio or running
your A/C, but even still the energy draw should be pretty miniscule),
the car uses zero watts when it's stopped. A gas car that is stopped
has to keep its gas motor running for the moment it's gotta getting
going again, not so with an electric motor.

When at high speed, the electric motor is probably hardly being used,
it's the gas motor doing all of the work. So the electric batteries are
being recharged during high speed life. At most, I think the electric
motors might kick in at speed when attempting to accelerate, so that
the gas motor will get a bit of an assist.

An over simplification. As I mention in another post, the Toyota hybrid
*system* allows for the use of a small gasoline engine (ICE) that
operates at higher efficiency than a normal car. All of the external
energy that runs a hybrid comes from gasoline. Yes, the system recovers
what would have been wasted through regenerative braking, but it is
the total system that achieves the high mpg results.

I admit thought that it is fascinating to observe the energy screen
display while in stop & go, or even stopped, traffic. The Prius has an
electric, variable speed compressor for its AC. In traffic jams leaving
Nationals baseball games in Washington, DC, this summer, we had our AC
auto-climate-control set to 70 degrees with outside temperature in the
80's and 90's, and the ICE would only run for a minute or two at a time
to keep the traction battery above the 40% SOC. Note: That in stop & go
situations, the system doesn't even try to charge the traction battery
back to "full" charge; it just keeps the battery a little above the 40%
SOC low point.

I have never experienced it, but apparently if one accelerates hard
enough and long enough (up a long grade perhaps) to deplete the traction
battery down to the 40% SOC, overall acceleration is reduced until the
charge can build up again. Nevertheless, Prius owners have successfully
driven up MT. Washington in New Hampshire and drive the mountain roads
out west without problems.

A final point of interest. Back in August, five guys drove a Prius
around a 14 mile loop near a motel in Pittsburg to see how far they
could go on one tank of gas. It involved stops and starts and they
never went over 40 mph. They went approximately 1400 miles on a little
over 12 gals for an average of approximately 110 mpg! The ICE only ran
27% of the time.

Ed P
'96 Outback 97 k miles
'04 Prius 37 k miles

 

[nothermark]

An over simplification. As I mention in another post, the Toyota hybrid
*system* allows for the use of a small gasoline engine (ICE) that
operates at higher efficiency than a normal car. All of the external
energy that runs a hybrid comes from gasoline. Yes, the system recovers
what would have been wasted through regenerative braking, but it is
the total system that achieves the high mpg results.

I admit thought that it is fascinating to observe the energy screen
display while in stop & go, or even stopped, traffic. The Prius has an
electric, variable speed compressor for its AC. In traffic jams leaving
Nationals baseball games in Washington, DC, this summer, we had our AC
auto-climate-control set to 70 degrees with outside temperature in the
80's and 90's, and the ICE would only run for a minute or two at a time
to keep the traction battery above the 40% SOC. Note: That in stop & go
situations, the system doesn't even try to charge the traction battery
back to "full" charge; it just keeps the battery a little above the 40%
SOC low point.

I have never experienced it, but apparently if one accelerates hard
enough and long enough (up a long grade perhaps) to deplete the traction
battery down to the 40% SOC, overall acceleration is reduced until the
charge can build up again. Nevertheless, Prius owners have successfully
driven up MT. Washington in New Hampshire and drive the mountain roads
out west without problems.

A final point of interest. Back in August, five guys drove a Prius
around a 14 mile loop near a motel in Pittsburg to see how far they
could go on one tank of gas. It involved stops and starts and they
never went over 40 mph. They went approximately 1400 miles on a little
over 12 gals for an average of approximately 110 mpg! The ICE only ran
27% of the time.

Ed P
'96 Outback 97 k miles
'04 Prius 37 k miles

Thanks Ed, this is the kind of information that helps the rest of us
understand the issues.

nothermark