I have a 2002 Prius. So far (2 1/2 years, 45 K miles) it has been the most
reliable car I've ever owned. Disclaimer: my daughter's '93 Accord has been
a clear second, considering it had 8 years and 163K miles at the time. I've
put a couple axles, a timing belt, brakes, a window regulator and an ignitor
in it in 4 years.
The question of hybrid battery life comes up all the time. The bottom line
is that everybody wonders and practically nobody has had problems. One
battery was destroyed by an insane hybrid control computer (both replaced
under the 8 yr/100K mile hybrid system warranty), another was punctured by a
stereo installer. Otherwise the Toyota_Prius' Yahoo group's 11000 members
have had no main battery failures, even though several are over the 100K
mile mark. I like to illustrate the point by pointing out a Google search
for "Acura transmission fail" brings up 17000 hits relating to why the Acura
transmissions fail and what to do about it, while a search for "Prius
battery fail" brings up about 9000 hits speculating when a battery would
fail but seemingly none on any that actually did. One hit refers to a
battery failing at 245K miles, but the reference doesn't take you to the
original source. I'm not aware of that happening, although a Prius taxi in
Canada was bought back by Toyota at about that mileage... the battery was
The Prius does have a 12 volt aux battery that is more troublesome and twice
the price of a normal 12 volt battery, though. Ours is still okay, but when
it croaks I'm going to make the adaptation to a more normal battery. The 12
volt battery just boots the computers and runs the brake pressurization pump
before the converter kicks in. I guess Toyota figured that meant they could
use a lawn tractor sized battery. The pre-2004 model also came with tires
that had a treadwear rating of only 160 (!) which lead to complaints of tire
life. I understand the current model has more normal tires.
There is no alternator, starter or even a transmission in the conventional
sense. The power steering and brake booster are electric, as is the A/C in
the current model. 12 volts for accessories and recharging the aux battery
comes rom a 100A converter when the hybrid system is "ready." Cruise control
is nothing more than an extra brake pedal switch and a control switch
assembly - everything else is just lines of code already in the hybrid
computer. Reverse is still the same gearing as forward, but the hybrid
computer tells the power train to back the car up, so it does. There is even
forward (or backward, in reverse) torque when in gear, very much like a
conventional auto tranny.
Honda's IMA system can be suped up, since it is essentially a conventional
power train with a boost from an electric motor. Toyota's can't, since the
entire system is under control of the hybrid computer. Adding a turbo, as
one turbo mfr has suggested doing, would certainly destroy the hybrid
transaxle. The engine is coupled to the transaxle by a torque limiter that
looks very much like a conventional clutch without a throwout, and the
"transmission" is simulated by generating AC from one motor/generator,
rectifying it and inverting it to drive the other motor generator. There is
some direct torque coupling but significantly increasing the engine output
would destroy one of the electronic parts immediately if the torque limiter
survived. Even putting headers on the engine can't improve the output,
because the hybrid computer would simply get in a snit about the power not
being as prescribed. For related reasons, the engine max rpm is held to 5000
rpm (maybe a little more on the current model?) by the hybrid computer. Not
the choice of teenage boys everywhere, but a huge plus for engine life I'm
The Honda system is adaptable to either manual or automatic transmissions.
The Toyota system is not available with a manual gearbox or automatic
transmission, only their "electronic CVT". Since there is no actual
transmission (it is a fixed planetary differential with two electric
motor/generators) there is no place to put a gearbox. Even if you found a
trick to do that, it would be hard to shift a car that won't even let you
decide when the engine runs. With the car in "park" I can press the
accelerator to the floor. The engine always starts, if off, and gradually
builds speed to some specific speed around 2000 rpm in a minute or two.
Well, good news so far, but I have always wondered what will happen 6-10
years from now when batteries need to be replaced in mass. Are they
recyclable? If not, will they have to be handled as toxic waste? If so, how
environmental friendly is that?
Toyota already has a program to buy them back for $200 and to recycle all
the metals. Few batteries probably will ever reach the point where they will
be replaced though - the battery is expected to last the design life of the
car. Individual cells can be replaced and the hybrid computer even has
diagnostics for determining if individual cells are performing properly. I
expect the overwhelming majority of Toyota's hybrid batteries will be sold
for the bounty when the cars are scrapped if current trends continue. There
are 1999 model year Prius cars in Japan and their batteries are doing fine.
On Thu, 19 May 2005 19:04:00 -0700, "Michael Pardee"
All batteries will 'last'. Define 'design life of the car' - 10 years?
less? Batteries degrade on 2 factors, time, and charge. Lead acid
batteries, for instance, degrade at roughly 10% capacity/year, even if
kept in pristine condition. NiMH tend to last around 8-10 years at
most. even if topped up - about the same life as a lead acid kept
optimum. So, according to you, a Prius is only designed to last 8-10
years? sounds like a poor investment to me. I know my 17yo civic's
still going strong. my 16yo volvo is utterly bombproof - nothings
needed doing in the 5 years i've had that, except for the routine
maintainance in the manual. tell me your prius will do that.
99 is only 5 years.Still well within life. I've got a niMH battery in
my MD recorder thats from 97, and thats still going strong, despite
having a hell of a lot more c/d cycles than that prius. 5 years
isNOTHING to a battery. 8-10 is the end of the life, even for the very
best batteries 9which include hawker sbs series, which is around $250
for a 30Ah 12V battery (also the ONLY lead acid batteries, that i'm
aware of, that can be checked into aircraft luggage)
Battery life is most strongly dependent on operating conditions. The flooded
lead-acids in our communication sites at work have a typical life of 20-30
years, and most of those are taken out of service with the capacity still
within specs (our battery guys load test them twice a year). They usually
fail because the positive terminal has "grown" out of the case. I guess
there is a chemical explanation for that phenomenon, but I don't know it.
Anyway, the NiMH main battery in the Prius is kept within a relatively
narrow range of state-of-charge, temperature controlled, and with charge and
discharge rates limited. It should be good for the life of the car, as
Toyota says. 15 to 20 years should be about right. I would be as surprised
at failures within 10 years as I would at lasting to 30 years. Toyota is
betting their own money there will be negligible failures before 8
years/100K miles (10 years/150K in California, IIRC), so I feel comfortable.
More than that, Toyota's credibility would suffer horribly if there were
such a rash of failures, and I won't insult Toyota's leadership by
suggesting they are that reckless. I think it's more likely they know
exactly what they are doing - a lesson our stateside companies should learn.
What is the design life of a car? Only Rolls Royce has had the nerve to
advertise that; they used to advertise 50 years. The standard in America was
implicitly 10 years for a very long time. Most quality cars, like Honda and
Toyota, are probably around 15 years - certainly more than 10, certainly
less than 20. Your Volvo and mine (an '85 765T) also had design lives in
that range. There is no percentage in making a car last 20 years, and 10
years builds a reputation for schlock (like GM, Ford and Chrysler have), so
the 15 year target is the sweet spot. It didn't work out well for my '85,
which has the French wiring that had a 5 year life, but that's life. At
least yours was built after the biodegradable wiring era.
The central point is that every individual car reaches the end of its life
sometime. It may be an untimely end in a collision, but more often it needs
a repair that the car is no longer worth. For my last Volvo, a 1970 145, it
was when the car was no longer worth putting a water pump in. (I never
thought to question what the life of the water pump is.) This '85 won't
survive its first turbo failure - at 235K miles it is overdue. I had a 1970
Mercury Capri that was no longer worth a U-joint, which was integral with
the drive shaft. It's always something. With the Prius it is very unlikely
in my estimation that battery failure will be a significant factor. I expect
at least 15 years from the car, and I expect the battery will still be
servicable at that point. If you feel differently, you'd be wise not to buy
On Sat, 21 May 2005 12:44:59 -0700, "Michael Pardee"
Then you have a very low level requirement. Its slightly erring on the
cautious side to say that lead acid capacity decreases at 10%/year
However, after 10 years, you're left at 35% capacity. oh, the load
will still be ok, but the caacity will be shot to hell. The growing
terminals are the exact same reason that the capacity drops - chemical
action.That 35% is also some eavy rounding. after 20 years, you're at
11-12% capacity. This is, as i remind you, keeping th batteries in
their optimum condition.treat them sub-optimally and they won't do
half as well.
Toyota has very little credability with me anyway, but then, are you
SURE its their money they're bettingwith? there's a long running
dispute between toyota and pastafont steel, for instance, where toyota
owes pastafont some $5m for steel its not paid for.
$5million+interest over 5 years buys a lot of hybrid battery sets. If,
however, your batteries are claimed to last 10 years, i'd be very
interseted ina bout 10 sets of them (I build Electrically powered
vehicles as a hobby) so i've contacted Matsushita, since this kind of
longevity is something Saft hasn't been able to give me with their
12Ah Sub-F cells (nice cells, especially the max discharge of
100A/cell, which moves the bottleneck to the controllers - a 1500A
150V controller isn't as easy to build as you might think - for those
that aren't up on your maths, thats about 300Hp, less losses to
20 years is the standard design life for communications lead-acid batteries,
although cell sites often go for the quick and dirty versions with 12 year
design life or less:
http://industrialenergy.exide.com/index.asp?gnb=2 and select "Flooded"
The load test is a complete capacity test; loss of 20% capacity is the
trigger for replacement. Most have less than 10% loss in capacity after 20
years and are usually budgeted for replacement within 30 years - earlier if
they show signs of case failure or (more rarely) loss of capacity.
I have a question for you. Do you know whether or not Toyota and Honda
informed people in the brochures related to their Hybrid vehicles about
the true nature of Hybrid vehicles? For example, do they (in their
brochures) warn people that if they plan to use their Hybrid vehicles
mainly on interstates and freeways that the miles per gallon will not be
I have seen several posts from Hybrid owners indicating that they were
shocked to learn that they only get great gas mileage (aka miles per
gallon) when they do lots of city driving. The makers of Hybrid vehicles
should inform people about the nature of Hybrid vehicles before they buy
them. I hope that they do it but don't really know since I have not read
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Rechargeable batteries are an odd creature. I have a little Milwaukee
power screwdriver (like the ol' Black & Decker "PowerDriver", but an
actual pro-duty tool) that came with two 2.4V NiCads, which have long
been notorious for short life, voltage fall-off and "memory effect".
The first battery I had to replace after *EIGHT YEARS* of regular use,
when it wouldn't take a charge anymore. The second finally gave out
three years later... or at least came close to giving out, before I
replaced it anyway. 15 years after I bought it, that driver is the best
$200 I ever spent.
Meanwhile, I've owned two IBM ThinkPad laptops, both using more modern,
supposedly more robust Lithium Ion battery packs. Both started showing
a marked decline in charge life after less than a year, to the point
that they wouldn't hold a charge at all after less than two years. I've
seen similar with several other LiIon laptop batteries as well. At
$200-$300 or more each, they're a pricy investment.
NiCds are "use it or lose it" type of batteries.If you use
infrequently,they do not hold up as well as if you use and recharge them
Also,using a "fast" smart charger (1 hour or less charge time)goves a
longer battery life.
ACtually, that depends very much on the model of the cell, and its
condition. There are ways to condition cells, but i don't reccomend
them to those unskilled, but it basically involves zapping the cells,
to break down the crystal biuldup 9conductive crystals form, which
produce a 'shotened' battery, hence the memory effect.
Condition them right, charge them, look after them, and they'll always
do you good, right to the end of their design life, and often beyond.
Me too. My previous new car was a 1984 Dodge (I plead insanity!) and it was
awful from the start. A carburetor rebuild in the first week, a wiring short
I spent all day chasing through the interior of the car the first year out
of warranty.... At 5 years age and 90K miles it needed a new timing chain.
Step 1: remove engine from car. The timing chain cover was blocked by the
wheel well when the engine was mounted. You get the picture. Honda and
Toyota forever! No Nissans - we shall not speak of that again.
On Thu, 19 May 2005 21:56:54 -0400, "Elmo P. Shagnasty"
You'd think so. Friend bought an 05 camry in december. Its been in the
shop 4 times, including headlight replacement, 3 times to fix the
airbag system (was on its last-lemon-chance) ABS problem This for a
car thats 6 months old, and 14k miles on it.... Oh, i should also
mention that there's already rust on the car (and this is georgia, it
don't rain that much!)
Toyota hasn't been the same since half the management resigned in 01,
and they switched steel suppliers to cheap south american steel
(whereas before, they'd been using high quality turkish steel, at
least for europe)
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