Gas Prices Rising

[ddn3f]

Re: Gas Prices Rising

Really? I can't believe that. Some cheap hyundai, honda or toyota has to be cheaper. What about those expensive batteries everyone speaks of.

Consumer Reports rated the Prius as the the car with the lowest cost of ownership: Cheaper insurance, gas, and maintenance costs.

[DSpencer]

Re: Gas Prices Rising

Really? I can't believe that. Some cheap hyundai, honda or toyota has to be cheaper. What about those expensive batteries everyone speaks of.

Maybe they count only the costs of ownership EXCLUDING the original purchase?

[evangellydonut]

Re: Gas Prices Rising

Maybe they count only the costs of ownership EXCLUDING the original purchase?

Sorry, as an engineer who worked with batteries in periphery on satellites and airplanes, I don't buy the claim that you don't need to replace the battery, especially when the age gets up there and the weather's been brutal. Lithium based battery is a time-based device and NiMH battery is charge based. Pick your poison, just don't pretend it's service free. (I lease a plug-in EV, so nothing against the technology as a whole)

Toyotas were much more bullet-proof back in the 90s. Their quality hasn't been the same since. I personally find it offensive to have a Corolla S (aka sport version) come with drum breaks and steel wheels w/plastic hub-caps. Hondas are preferred IMHO.

[don]

Re: Gas Prices Rising

Preliminary pricing puts both Civic and Corolla in the $20k range new and $5-6 less used with not excessive (well north of 30,000) mileage.

[DSpencer]

Re: Gas Prices Rising

Sorry, as an engineer who worked with batteries in periphery on satellites and airplanes, I don't buy the claim that you don't need to replace the battery, especially when the age gets up there and the weather's been brutal. Lithium based battery is a time-based device and NiMH battery is charge based. Pick your poison, just don't pretend it's service free. (I lease a plug-in EV, so nothing against the technology as a whole)

Toyotas were much more bullet-proof back in the 90s. Their quality hasn't been the same since. I personally find it offensive to have a Corolla S (aka sport version) come with drum breaks and steel wheels w/plastic hub-caps. Hondas are preferred IMHO.

To clarify, I was just speculating on how it could even be close given that a Prius costs much more than other cars. Wasn't trying to imply the study was correct or that the battery would last forever.

[Polish_Silver]

Prius batteries

Sorry, as an engineer who worked with batteries in periphery on satellites and airplanes, I don't buy the claim that you don't need to replace the battery, especially when the age gets up there and the weather's been brutal. Lithium based battery is a time-based device and NiMH battery is charge based. Pick your poison, just don't pretend it's service free. (I lease a plug-in EV, so nothing against the technology as a whole)

Toyotas were much more bullet-proof back in the 90s. Their quality hasn't been the same since. I personally find it offensive to have a Corolla S (aka sport version) come with drum breaks and steel wheels w/plastic hub-caps. Hondas are preferred IMHO.

Toyota claims that very few of the batteries ever need replacement. Supposedly, they use the NiMH very carefully. I think they have switched to Lithium. Are there any stats on how long they last?

[GRG55]

Re: Gas Prices Rising

Consumer Reports rated the Prius as the the car with the lowest cost of ownership: Cheaper insurance, gas, and maintenance costs.

Not likely that will be the case. Complexity is rarely cheaper than mechanical simplicity.

The Prius has a 1800 cc engine with variable valve timing (VVT). That's 300 cc more displacement than my first car, an econobox Volkswagen. The main reason for the complexity of the VVT is to simulate an Atkinson cycle (instead of a conventional Otto cycle) where valve timing is used to ensure the compression ratio is less than the expansion ratio resulting in more of the heat from the combustion process to be extracted. The need for the larger engine displacement is to overcome a portion of the lower power density that results from the modified cycle.

Regardless, that complicated engine has to be maintained just as any gasoline engine in any of the other cars under consideration.

So unless the electric motor/generator, the Ni-MH batteries, the hybrid drivetrain and all the other stuff that makes the Prius unique are completely maintenance free I seriously doubt the maintenance costs over the full life cycle of the car are lower than a conventionally powered Otto cycle or Diesel cycle vehicle.

I would also venture that replacement wear parts for the Prius are going to be rather expensive given the unit production rate is nowhere near the volumes of Toyota's other vehicles, and there doesn't appear to be a great deal of parts commonality with their other models...

[evangellydonut]

Re: Prius batteries

Toyota claims that very few of the batteries ever need replacement. Supposedly, they use the NiMH very carefully. I think they have switched to Lithium. Are there any stats on how long they last?

There are tons of papers on how to model Ni-MH and Li-Ion batteries in automotive usage but none really had a "in conclusion, the average hybrid electric vehicle will last 200k miles" kind of statement, I'm guessing due to funding reasons... These data is highly protected by the manufacture, but at least we can get an idea of things affecting battery life. For example "exposure of a Ni-MH battery to a temperature of 45C will decrease its cycle life by almost 60%." A large part of battery life is also dependent on how much it was discharged before recharging, known as "depth of discharge." Although DOD effect in Ni-MH can be mostly removed from a proper discharge/charge cycle, it's none-trivial to ensure each of the cells are discharged only to a certain amount before risking charge-inversion and bricking that cell. That's why Toyota gives a $1500 credit for older hybrids (and charge $3,500+ on average for replacement), as they can easily recondition the batteries.

In a practical usage case, places that are too cold will cause higher DOD rates, wearing out battery faster but less memory effect. Places that are too hot will cause the temperature effect described above, which will permanently harm the battery. Only if you are in places like California and Hawaii, might the climate be nice enough to get optimal life out of hybrids... So having average stats doesn't make too much sense from manufacturing or consumer point of view.

Anecdotally, I feel (nothing scientific, only based on gut) that the Lexus RX400h lost maybe 20% of it's battery life after 5 years and 55k mi, but harder to gauge as the computer will help mask the effect and can only guess based on charge/discharge pictures Toyota provides. BMW ActiveE lost maybe 5% after 1 year and 10k mi, which is much more significant since it's a 100% plug-in electric. Both vehicles are primarily operated in Southern California.

[GRG55]

Re: Prius batteries

The hybrid manufacturers must be having to balance and manage the simultaneous discharge from the traction load with the re-charge from the gasoline powered generator and then throw into that mix the regenerative braking effects. Those must be some fancy computers & software that maximize the life of the traction battery pack...

[Polish_Silver]

Re: Gas Prices Rising

Got to read up on Atkinson---sounds very interesting. But my understanding was that the hybrids could run the engine over a narrow range of speed, leading to considerable advantages in efficiency, including needing a smaller displacement engine.
(Gas engines work well over a wide range of speed, however). But it seems part of the prius efficiency comes from a more complex engine, not just the electric power system.

[shiny!]

Re: Gas Prices Rising

Toyotas were much more bullet-proof back in the 90s. Their quality hasn't been the same since. I personally find it offensive to have a Corolla S (aka sport version) come with drum breaks and steel wheels w/plastic hub-caps. Hondas are preferred IMHO.

My Accent came with all-wheel disc brakes and cost ~$17,000 new... about $7,000 less than a Prius hatchback. $7,000 will buy a lot of gas!

Filled up on the way home tonight. Chevron gas at $379/gal in Scottsdale :-(

I'm getting 35 MPG :-)

[touchring]

Re: Prius batteries

Toyota claims that very few of the batteries ever need replacement. Supposedly, they use the NiMH very carefully. I think they have switched to Lithium. Are there any stats on how long they last?

I don't know about car batteries, but my laptop batt used to last 2.5-3 hours when new. After 3 years of usage, they last only 1.5 hours. I use my laptop as a pc, rarely bring it out, perhaps only once every 2 weeks, so I'm sure the batts are not used when the laptop is plugged into mains? ;)

[aaron]

Re: Gas Prices Rising

To clarify, I was just speculating on how it could even be close given that a Prius costs much more than other cars. Wasn't trying to imply the study was correct or that the battery would last forever.

Toyota Prius C	$5,000
Toyota Corolla Base	5,250
Honda Fit (base)	5,250
Smart ForTwo	5,500
Honda Fit Sport	5,500
Mazda2 (MT)	5,500
Scion xD (MT)	5,500
Toyota Yaris Hatchback	5,500
Scion xD (AT)	5,750
Toyota Corolla LE	5,750

Cost/year over 5 years



I will have to dig up the other articles (It had long term estimates). There have been very few complaints of battery problems in the Prius... they have been on the road a long time now so they have good data. Yes, Toyota has the best hybrid technology. We have a highlander hybrid... I can get 29 mph in the summer. It is amazing.

"The factors included in our owner cost estimates are depreciation, fuel, interest on financing, insurance, sales tax, and average maintenance and repair costs you can't find anywhere else."

Toyota Camry hybrid was #1 for the family category
Toyota Prius V was #1 in the wagon/minivan category

They assume a gas price of 4 dollars. Depreciation is the biggest killer in terms of cost.

[FrankL]

Re: Prius batteries

I don't know about car batteries, but my laptop batt used to last 2.5-3 hours when new. After 3 years of usage, they last only 1.5 hours. I use my laptop as a pc, rarely bring it out, perhaps only once every 2 weeks, so I'm sure the batts are not used when the laptop is plugged into mains? ;)

Your laptop battery will slowly discharge by itself over time. If you do not run some sort of battery charging software, your OS and drivers will instruct to recharge up to 100% as soon as it drops just a tiny bit below 100%.

From what I understand, this is pretty bad for lithium-ion batteries in long term.

On my Thinkpad, there's a program to manage the battery charging. I've set it to start charging only when the battery level drops below 70%, and stop charging at 90%. I've barely used my battery over the past 3 years (less than 40 complete discharge/charge cycles), and the power manager reports that it holds 95% of original capacity. This is for a 4 year old 9-cell lithium-ion battery pack.

[Polish_Silver]

lap top batts

I don't know about car batteries, but my laptop batt used to last 2.5-3 hours when new. After 3 years of usage, they last only 1.5 hours. I use my laptop as a pc, rarely bring it out, perhaps only once every 2 weeks, so I'm sure the batts are not used when the laptop is plugged into mains? ;)

I think your experience is typical. I often discharged my laptop completely, which shortens the life of the batteries. Toyota went to great lengths to prevent this happening in the hybrid. Since the engine can start when needed, the battery never gets deeply discharged.