Hybrid auto road trips

Given this, if the electric motor/batteries are used to assist the IC engine at high speeds (and/or uphill grades, I assume), how does performance change when the batteries are drawn down to their min level and the electric motor goes offline? Does the IC engine have the reserve capacity to keep the car at 75MPH (or at, say, 60 MPH on an uphill grade), or do you need to back off a bit?
The electric motor is only used to assist the ICE at high speeds/acceleration/grade if it's within it's design charge range. The Prius will not let you drive the traction battery down to no charge. If the battery reaches it's low charge level, you basically have an underpowered but useable ICE car, while the battery is recharged.

For the Prius, and I suspect other makes, the traction battery is kept in a pretty narrow range of charge. While I've seen several different claims as to what those ranges are, I believe they are normally charged between 40-60% of maximum to prolong battery life as well as allowing "headroom" for regenerative braking. If you drive uphill long enough to reach the low charge level threshold (not very low), the car will not draw from the battery, you'd be driving on ICE only - and the Prius will climb any hill with ICE only albeit without much reserve HP for passing, etc.

I haven't climbed Pikes Peak with either of our hybrids over the past 5 years, but I've never seen either car running on ICE only. It uses EV alone (low speeds, downhill) when possible and both when needed mostly. If there's a red traction battery display or warning, I've never seen it...
 
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Regarding the A/C of the Prius, I have seen the story of a woman who traveled and slept in her Prius. The A/C kept her comfortable in the summer nights, as the engine would restart to keep the battery in charge as needed. Really neat! I wonder if too many charge/discharge cycles would shorten the battery life though.

The electric motor is only used to assist the ICE at high speeds/acceleration/grade if it's within it's design charge range. For the Prius, and I suspect other makes, the traction battery is kept in a pretty narrow range of charge. While I've seen several different claims as to what those ranges are, I believe they are normally charged between 40-60% of maximum to prolong battery life as well as allowing "headroom" for regenerative braking. If you drive uphill long enough to reach the low charge level threshold (not very low), the car will not draw from the battery, you'd be driving on ICE only - and the Prius will climb any hill with ICE only albeit without much reserve HP for passing, etc.
On long climbs, yes, I have seen hybrids crawling up hill. But for a guy having all the time in the world like I do, I would not consider it a drawback. These still go up hill faster than my MH towing a toad.
 
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Regarding the A/C of the Prius, I have seen the story of a woman who traveled and slept in her Prius. The A/C kept her comfortable in the summer nights, as the engine would restart to keep the battery in charge as needed. Really neat! I wonder if too many charge/discharge cycles would shorten the battery life though.


On long climbs, yes, I have seen hybrids crawling up hill. But for a guy having all the time in the world like I do, I would not consider it a drawback. These still go up hill faster than my MH towing a toad.

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How long does the Prius battery last and what is the replacement cost?

The Prius battery (and the battery-power management system) has been designed to maximize battery life. In part this is done by keeping the battery at an optimum charge level - never fully draining it and never fully recharging it. As a result, the Prius battery leads a pretty easy life. We have lab data showing the equivalent of 180,000 miles with no deterioration and expect it to last the life of the vehicle. We also expect battery technology to continue to improve: the second-generation model battery is 15% smaller, 25% lighter, and has 35% more specific power than the first. This is true of price as well. Between the 2003 and 2004 models, service battery costs came down 36% and we expect them to continue to drop so that by the time replacements may be needed it won't be a much of an issue. Since the car went on sale in 2000, Toyota has not replaced a single battery for wear and tear
 
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On long climbs, yes, I have seen hybrids crawling up hill. But for a guy having all the time in the world like I do, I would not consider it a drawback. These still go up hill faster than my MH towing a toad.
Agreed. We rented a Prius last time we were in San Francisco. The Prius did fine and there's no danger of hurting the battery or the ICE, but it was clear the Prius was not enjoying the hills of San Francisco. Passing uphill on the many steep grades would have been out of the question...
 
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Why, there should have been a town called Armadillo in Texas.

Amarillo or Armadillo, it still conjures up the same animal in people's mind. My next RV trip will take me through there, most likely.
I was really, really hoping Amarillo (which means Yellow, by the way), had officially changed it's name to Armadillo. :D

If you take your RV, don't miss the awesome Palo Duro Canyon State Park.
 
We did it in the opposite direction on the way there, and as I said earlier, I've never had less than 45mpg on a long trip. I often get less than 45 mpg around town where we live because our average trip durring a tank of gas is ~10 mins and everywhere is flat.

According to the car's computer, I've never gotten less than 50mpg...
 
I was really, really hoping Amarillo (which means Yellow, by the way), had officially changed it's name to Armadillo. :D

If you take your RV, don't miss the awesome Palo Duro Canyon State Park.

+1 on Palo Duro Canyon. We've been twice now, and it is awesome.
 
Can you run the A/C on the battery without the engine for 3 or 4 hours so you can take a nice nap at rest areas without outside heat and bugs?

As noted by others, yes because the engine will start periodically to charge the batteries. And it a quiet instant engine start, not a noisy, slow start like most cars with small starter motors. The electric drive motor spins the IC engine to speed instantly. It's pretty unobtrusive and should be less likely to wake you than cars zooming past on the nearby highway or people slamming car doors heading to/from the rest stop's restroom.
 
The electric motor is only used to assist the ICE at high speeds/acceleration/grade if it's within it's design charge range.
I think the real purpose of the electric motor is to enable the driver to peel rubber as soon as the light turns green, and not have the engine start up until you're nearly across the intersection...
 
I think the real purpose of the electric motor is to enable the driver to peel rubber as soon as the light turns green, and not have the engine start up until you're nearly across the intersection...

+1 :LOL:

Since the electric motor has maximum torque at low rpm, assistance with getting the car rolling is where it saves most gas.
 
Good reading as we are really interested in purchasing a Prius. I must clarify that by saying my WIFE is interested. She is interested in fuel economy although she has a lead foot and is a speed demon. Can't talk to her. I can average 22 mpg on our Honda CRV and she can't get over 18 mpg when she is driving. She is a terrible driver when it comes to fuel economy. Yet, she wants to get involved in "the environment" by becomming more fuel conscious. :mad:ARGH! Also, we only drive about 9K/yr. Hardly worth focusing on fuel economy. However, I'm still interested in the newer vehicles that offer hybrids, etc.

Last week I stopped in to the local Chevrolet dealer to see how I fit in an Equinox SUV compared to the tight fit I have now in our Honda CRV. While there and talking to the sales person who sold me a Chevy a few years ago, I got him to show me a Chevy Volt. I could tell right off that I would like it and it was intriguing. However, no power seats! That's a deal breaker right there. Salesperson said there was just too much drain on the batteries. This may not be a problem on a hybrid but I can see how it would be on an electric car. Why not a separate battery? Weight?
Just curious.
 
While there and talking to the sales person who sold me a Chevy a few years ago, I got him to show me a Chevy Volt. I could tell right off that I would like it and it was intriguing. However, no power seats! That's a deal breaker right there. Salesperson said there was just too much drain on the batteries. This may not be a problem on a hybrid but I can see how it would be on an electric car. Why not a separate battery? Weight?
Just curious.
Power seats would add another 30 lbs on a vehicle that's marketed all about efficiency. The EV range on the Volt is marginal (high for a PHEV, but low compared to an EV) and they're pretty pricey already (as you probably noticed), power seats would reduce range a little and make the price even higher.

But the real reason is, they want you to buy a Cadillac version of the Volt one day. It'll have power seats, at a price... :D
 
.......... However, no power seats! That's a deal breaker right there. Salesperson said there was just too much drain on the batteries. This may not be a problem on a hybrid but I can see how it would be on an electric car. Why not a separate battery? Weight?
Just curious.

This makes no sense. While the power seat may pull a modest load while being operated, the running time on average, has to be about zero. I suspect the decision was made to cut weight.
 
I realize we're getting off topic here from what Chuckanut was asking. I guess that's why I like this forum so much. With the occasional exception (perhaps someone having a bad hair day), those of us who stay at least within 90 degrees either side of the topic rarely draw too much ire.

So, FWIW, I'm completely fascinated by the concept (and technology) of wringing the most "work" out of a given quantity of energy (from LEDs in lighting to hybrids and EVs for transportation.) Perhaps I flatter myself, but even though I have no engineering experience and very little practical mechanical ability, I believe I have (mentally) designed a car which could get 60 or even 70 mpg. The thermodynamics are favorable. It's mainly a matter of reusing the wasted energy of the typical ICE. The hybrids already do a good bit of that, but there's a lot of potential left when you consider that a typical ICE is at best about 20% efficient (15% might be a better figure, but it varies). Now, the only problem is that to actually build my "dream car", it would probably cost way more than it would ever save in fuel costs - at least at $4/gallon.

So... To get to my real point (finally!). Once we conclude that hybrids are "real cars" and that you can "live" with them and actually travel with them, I still struggle with the whole concept of spending an extra (How much? 20% more for new to 80% for used) pile of money to buy a hybrid rather than a regular car. I'll give one example from personal experience. My 19 year old "beater" on the mainland finally had to be shot between the head lamps last year (actually - I sold it for $100 to a guy who drove it for ANOTHER 10 months). I replaced it with a "shiny" old 2000 Buick tank for $5500. Between some (questionable) suspension work and (not questionable) new tires I put another $1500 into it. I drove it 7,000 miles without a hiccup. I expressly bought THAT car because I knew we would put a lot of road miles on it. On the road, it got better than 30 mpg (70/75 mph). I drove a one-day stretch from St. Augustine FL to Chicago and my 65 year old arthritic back didn't hurt. At the end of our mainland stay, I stored the vehicle for next year (free with a good buddy). I'm sure I could have gotten my $5500 back out of it at that time (still had just 70K on it and KBB says $5700 to purchase).

Even at 55 mpg with a shiny new hybrid, I don't think my $/mile could be beat (not even close). All of this is debatable, of course. If someone is fascinated by the technology (as I am) maybe it's worth the extra cost of the hybrid. Otherwise, I think the best argument would be the "reliability" of new vs used. Personally, I maintain my car and also have AAA. So, to Chuckanut, I would say, you've probably received excellent advice as to the "livability" of a hybrid. If that was the only remaining question you had prior to purchase, I would have to say "just do it" and enjoy. If you still have questions about the costs, I'm sure our local hybrid owners would love nothing better than to regale us with their tales of mpgs. I too would love to hear the stories, but I think I'll keep my Buick a while longer. And guess what? YMMV:cool:
 
Good reading as we are really interested in purchasing a Prius. I must clarify that by saying my WIFE is interested. She is interested in fuel economy although she has a lead foot and is a speed demon.
Hey, your spouse can cut a break here.

When you're stopped at an intersection, the Prius shuts off its engine. You can't rev the engine when you're stopped.

If you leadfoot a Prius, the electronics tell the engine to start up. The motor generator is already spinning the front axle (on battery power) so you're already moving, and it also engages the engine to start spinning it. Once the engine has spun up to 800 RPM then the fuel injectors start squirting gas into the cylinders, and the engine fires up.

So the most fuel-efficient way to roll out of a stop is to accelerate firmly. That wastes a lot of gas in a conventional vehicle, but it's the preferred fuel-conservation method in a Prius.

When you stomp on the brakes, the Prius tries to slow down with its motor generator first-- which puts some energy back into the battery. So if you've been going too fast and have to slow down, at least a little of that braking is converted back to battery power.

As for the speed part, it's a four-cylinder engine. That's as much consolation as I can offer there. But the battery and the regenerative braking smooth out a lot of the abrupt changes in engine RPM.

I suggest that you guys join PriusChat.com and start reading up on your preferred model. Ask questions. Buy on Craigslist, not from the dealer. Better still, buy from a PriusChat owner in your area. Their PriusChat reputation depends on the quality of the car and how they treat you.
 
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Good reading as we are really interested in purchasing a Prius. I must clarify that by saying my WIFE is interested. She is interested in fuel economy although she has a lead foot and is a speed demon. Can't talk to her. I can average 22 mpg on our Honda CRV and she can't get over 18 mpg when she is driving. She is a terrible driver when it comes to fuel economy. Yet, she wants to get involved in "the environment" by becomming more fuel conscious. :mad:ARGH!

I get a bit irate when I ride with DW. Same thing with mileage. I'll get 25 to her 20 most tank-fulls in her SUV. I anticipate traffic lights and traffic slow downs. She's still on the gas when the light ahead is red. One time I really upset her. I asked if the car she used in Drivers Ed was a Kiddie Kar (peddles for motivation - like a bike). She gave me a strange look. I said "Apparently, you don't consider it driving if you're not pushing a peddle. If you're not pushing the brake, you're pushing the gas." It was not a fun trip from there. Now, I just try to keep my mouth shut. A few bucks worth of gas is cheaper than divorce.
 
DW's Camry Hybrid has almost 70K miles on it and my Prius has 8K. The Prius did 1500 miles to from NC last year and the Camry has several 1000-2000 mile trips on it thru hot, very cold & elevations. I wouldn't have any reservations about a hybrid on a trip of any length or elevation, they're not different in use than an ICE car IMO. I'm trying to imagine what your concerns might be?

My concern was that on long trips or uphill drives over big mountains, the gasoline engine might not have the stuff needed if the electrical motors ran out of juice. I was also concerned with the heat buildup from a long trip causing battery problems. But, from what I have read here that is not an issue. I do appreciate the feedback from real people who have used these cars under real conditions, not just on a test track.
 
I just did a quick look at the technical info, and am surprised that the Prius battery does not really hold that much energy. From Wikipedia,

The traction battery is a sealed 38-module nickel metal hydride (NiMH) battery pack providing 273.6 volts, 6.5 A·h capacity and weighing 53.3 kg (118 lb)[114] is supplied by Japan's Panasonic EV Energy Co. They are normally charged between 40–60% of maximum capacity to prolong battery life as well as allow headroom for regenerative braking.

The energy storage is 273.6V X 6.5 Ah = 1780 Wh. How much is that? To picture it, suppose we use up the entire battery capacity and not just 20% like the Wiki says for longevity, let's see how high we can lift the car with that energy.

So, 1780 Wh = 6.408 MJ = 4.7 million foot-pound.

If the car weight is perhaps 3400 lbs with 2 passengers, then ignoring all drag and inefficiency in conversion, that energy can drive the car up 1380 ft in elevation. If the battery charge/discharge is limited to 20%, and if we consider the various inefficiencies and losses, then the useful energy storage would be a lot less.

By the way, two golf-cart lead-acid batteries may be close to the weight of the above battery. They store 12V X 200 Ah = 2400 Wh. RV users typically limit the depth of discharge to 50% for battery longevity. However, they usually last only 3 or 4 years, or 1000 to 1200 cycles.
 
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My concern was that on long trips or uphill drives over big mountains, the gasoline engine might not have the stuff needed if the electrical motors ran out of juice.
The battery supplements the engine and smooths out the torque curve. It doesn't replace the engine, but rather gives it someplace to store the excess energy and re-use it later. Otherwise the engine is powerful enough to haul in excess of its rated capacity, but I'm not sure if it's rated for towing.

The car has at least 13 computer controllers. Its motto should be "It just drives"...

I was also concerned with the heat buildup from a long trip causing battery problems.
There have been times when passengers (or large, hairy dogs) have blocked the main battery's air intake ventilation filter in the back seat. It's rare, and it gives plenty of warning when it happens, but it still seems to happen once or twice a year.
 
Why, there should have been a town called Armadillo in Texas.

Amarillo or Armadillo, it still conjures up the same animal in people's mind. My next RV trip will take me through there, most likely.
Since the Jim Bowie Restaurant in Bowie, Texas, burned several years ago, we now eat at the Armadillo Grill in Bowie. We have to watch what we eat because we want to have a good appetite when we arrive at the Big Texan Steak Ranch in Amarillo.
 
Great thread! Even if we get off topic a little, it sometimes serves the purpose. One post I expected and never got: can you get power seats in a Prius? If not, that's a deal breaker. Wife must be able to touch a button and have seats move to her preferred position. We don't have that now in the Honda CRV but that is what she wants.
 
I did a Web search on "Armadillo Grill", and there are several throughout the country. Wonder if it is a restaurant chain, or just a common and popular name for a steak house.

Anyway, back on the hybrid EVs, it appears that the main reason for their high MPG is that the electric propulsion is mainly to provide a boost for short-term acceleration, so that the combustion engine can be of a smaller size. Indeed, when going up a long climb, the battery would run out fairly quickly.

It will be a long time before hybrid engines can be practical for RVs. Heck, before anything else is done, they should design these motorhomes so they do not all look like a brick!

Aerodynamic drag is a huge effect in autos. I have told this story before, but it is worth repeating. In between my two homes, whose elevations are several thousand feet apart, I have driven many vehicles over this familiar highway. Observing how a vehicle coasts down a 6% slope tells you a lot about its aerodynamic drag. My minivan would slowly speed up past 75mph over a mountainous stretch and I would have to brake to avoid going over the rail. My Nissan SUV would max out at about 70mph terminal velocity. That's terrible! That explained why the SUV had such bad gas mileage, compared to the minivan which is heavier and has a bigger engine.

And about the motorhome dragging the toad, forget it! I occasionally thought I needed to give it gas to go downhill at 60mph. Good grief!
 
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With a lot of BBQ sauce? Or should I order it spicy?
 
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