Battery or Batteries

It's one big block of batteries.. that block of batteries should last over 200k miles. Your transmission will never burn out.. so... by the time your battery dies, it will cost a lot less to replace and would probably be replaced by Lithium Ion.

If the battery does die within the warranty time.. it will be replaced for free. Overall... oil every 5k instead of 3k.. less cost in fuel.. etc.. etc.. the prius cost a lot less than any other car.

I drive almost 200 miles a day in my prius. After doing the math a while ago.. i save over 2000 gallons a year in fuel compaired to my old car.. oil changes is a lot.. along with basic maintenance. the savings over the life of the car will probably equal the amount of the car.

 

lol.. efusco posted before me.. damn you efusco. lol

you do phrase it all much better than me though.

 

here is what the battery looks like without the cover.

 

*looks away* can't look.. can't look.. might want to see it in person.. lalalalalala *runs away* lol

I have to keep telling myself to NOT take the car apart.. i'm soo curious though.

That battery setup almost looke like these: http://www.peve.panasonic.co.jp/e_catalog1.html

er.. a lot of those.. *shrug*

 

Only the original version of the Prius used "D" (cylindrical) cells. All Prius made since 2001 have used prismatic (flat/rectangluar) cells. These are more expensive but can be packed more efficiently.

 

OK, this confirms there's some interest in this project.

I'm trying to shoot some (boring, technical) documentary footage which explains this. I'm meeting with a professor of physical chemistry (or inorganic chemistry, not sure which) on Tuesday and shooting an interview which will hopefully include a battery-chemistry primer.

Based on what I've learned (partly through research, but mostly through people on this forum just giving me the answers ) the HV battery should last the life of the vehicle.

First of all, the battery is used for starting the engine (which doesn't discharge it much at all) and for supplemental power during normal driving. The gasoline engine is really underpowered by most standards, but the car supplements that weak engine power with battery power when needed.

In most driving scenarios this means you'll only use very short pulses of extra power from the battery. Holding the gas pedal down for too long has this way of making you go really fast. So you'll usually only discharge the battery a tiny amount, when getting up to speed on the Interstate (for example).

Exceptions to this rule would be climbing mountains (not hills, mountains -- something so steep and long you need to worry about brakes overheating on the way back down) or driving over 100 MPH on a racetrack. Both of those applications require lots of sustained power for a long time, so you need to remove a *lot* of power from the battery now, and then put a *lot* of power back in the battery later.

This is important, because one of the two ways a battery can fail is from gradual chemical breakdown caused by age and wear-and-tear. As this Prius battery product page shows, the battery still has around 85% of its capacity after 8000 *full* charge/discharge cycles, or many many more partial cycles. That takes well over a hundred thousand miles to accomplish (unless you're beating the battery up on purpose), probably closer to two or three hundred thousand miles. And even then, you don't need the battery replaced -- you just have less capacity. Since most people rarely see a full charge and rarely see an empty charge, this might not even affect people. (Until you take your quarter-million-mile Prius up Pikes Peak and you figure out your 20 year old battery can't keep up with those constant high power demands any more, lowering your climb speed. Does just fine in traffic, though.)

The second way a battery can fail is from just plain physical breakdown. A weld could come loose, a battery could be manufactured incorrectly and die, etc. If this happens, you only have to replace that single battery -- and they currently cost around $200 each. Old Mill Toyota's parts department quoted me $4823.41 for the entire 28-battery pack on March 10. That quote was for just some random guy coming in and buying the battery pack with no old pack to recycle, no vehicle to put it in, no warranty, just cash-and-carry. Your replacement cost will definitely vary.

This physical breakdown is a bit less likely in the 2004-2005 Prius anyway, because the battery doesn't get as hot. http://www.nrel.gov/vehiclesandfuels/energ...hive_prius.html

Hope this helps!

--Michael Spencer

 

I guess another way to think of it is: it's another "major repair" item to worry about as the car approaches the end of its life. In most cars you have to worry about the engine, transmission, and suspension, and each of those could possibly develop expensive-to-repair defects. (At least these are the things I worry about with my current 1994 Mercury Sable, which will definitely be replaced with a new Prius as soon as I can afford it )

In the Prius, there's a fourth expensive item which can go wrong: the battery pack. But I think that's compensated for by the design of the other components.

The engine is less likely to fail. First, the engine never starts. Well, OK, one moment it's not turning and the next moment it's running, and something happens in between -- but it's not a normal engine start. In most cars, a weak battery and weak motor spin the engine at a low rate (say, 200 RPM), and then a "shock" of rich air/fuel mixture is added and combusted. This gets the engine up to normal running speed quickly, but it also causes more wear and tear by pushing parts against each-other pretty hard, especially at a time when there's very little oil pressure. By contrast, the Prius never starts its engine like that. Powerful batteries and motors spin the engine at full running speed under no stress -- no combustion at all. The oil pump is started, so the engine is fully lubricated already, with full oil pressure. Only after all that's done is a *normal* air/fuel charge added, starting one cylinder at a time. So in effect, the engine never gets started, it just ...well, you know what I mean. Also, since the car operates without its engine some fraction of the time, the engine will age a little more slowly than normal.

The transmission is *much* less likely to fail. This design is what really got me into the Prius -- there are no grabby friction surfaces to wear out in the Prius transmission. Everything is always in gear, always meshed. No clutch to wear out, like in manual transmissions, no clutch packs or bands to wear out, like in automatic transmissions. Graham's Toyota Prius page explains it pretty well.

I don't think the suspension is any different from a normal car, so normal wear and tear on that.

I know general reliability wasn't what you asked about, but I hope this helps too.

 

First look at a 2nd gen Prius battery Frank. Haven't had to dig into one of those yet,but have done lots of the 1st(40G). From what I have read in the manual and the inside of yours,looks like it would take longer to remove then the previous versions.More trim to remove. And by the way,why is yours disassembled? :roll:

Your really digging into this report aren't you Michael? Thanks for all the info you post. It even helps me with some of your research You can never know to much or stop learning,is what I always say.

 

Thanks Rick. When I finally get to buy my Prius, I wonder if I'll qualify for some kind of award: most pre-purchase research EVER performed by a consumer.

(By the way, do you mind if I PM you, or ask you a question on that other thread? Eventually I want to try to interview someone at Toyota, but I'm a complete nobody with no video-making experience, and I don't know how open they are to communication. I wanted to talk to someone "on the inside" who could give me some pointers about how to approach an interview request. Before anything, I imagine they'd want to see what video I'll already have shot, so they know whose side I'm on...)

 

Rick57 here's your answer and as you can see I drive a classic and I still stand by what I said in the post. She took the trunk floor plate out the day it came home from the body shop.
http://priuschat.com/forums/viewtopic.php?t=1412

 

Inorganic, piece of cake, Physical Chemistry, shutter, twitch flash back nightmare. These are not the same thing take it from a old Chem Major. Never confuse the two.

 

His faculty page on UNO's web site says physical chemistry. But I thought it was inorganic chemistry when someone referred me to him. What's the difference? (Maybe I can impress him a slight amount when I meet him again for the interview on Tuesday. )

Ack, thread getting hijacked...sorry...

 

Well at an under grad level inorganic is everything but carbon. P chem is one semester of Thermodynamics and one of Quantum Mechanics. For the whole year we used 10 English word after that it was all mathematics. Now I have been told that it is a language but it is not one I think in. I scraped out with a B and considered myself very lucky. Most Chem majors that don't go into P chem will agree that is one tough course. These folks think in equations (shutter), they are inhuman.

 

You heard ten English words in your Physical chem course? I envy you... my P. chem prof was Italian, and barely spoke a word of English. Since I understand neither Italian nor mathemathese, I decided to admin defeat and return to hiding in the biology department after the first term.

Inorganic and organic were enjoyable, from what little I remember of them.

What were we talking about again?

 

lol