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7500 cycles would be 300k miles.

" By the end of December, GM will have completed 300,000 miles on the Volt full vehicle simulator, or about three times the design life of most components. "

" In the lab, the packs have accumulated over 300,000 miles of simulated customer use testing which involves cycling the batteries through routines based on real world driving and charging use. "
 

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Biggest uncertainty will be calendar life. The only way to really know what will happen in 10 years is to wait 10 years.
 

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My question is; is this 300,000 miles on one pack, or 300,000 miles cumulatively on several packs? In other words, is this just six packs going 50,000 miles each?
 

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My question is; is this 300,000 miles on one pack, or 300,000 miles cumulatively on several packs? In other words, is this just six packs going 50,000 miles each?
Its not clear, my impression that this is cumulative among all the packs on test. Note the plural packs:

"In the lab, the packs have accumulated over 300,000 miles"

Lets say 6 hours to charge a pack (could also be charged in 1 hour), 1 hour to discharge it.. that would allow 1250 cycles in one year, a total of 50k miles of testing per pack. If you allow 1 hr charges then that changes to 175k miles of testing per pack per year. 1hr recharge should not stress a pack, its only a 50% SOC and its liquid cooled. Since they are simulating user patterns then they probably will not use a 1hr quick charge.

When did they start testing these packs?
 

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How does this testing compare with other new models?

I presume that any time a new car or new engine is developed that GM does some fairly rigorous testing to estimate the lifetime of the component. So if the 300,000 simulated miles is right how does this correspond to normal new stress testing? Is 300,000 miles normal for a new engine component? How do the Volt components compare with other major components in new applications? I wonder how the other component testing is going also: traction motor, generator/genset, control electronics. I presume that the traction motor is pretty reliable, but it will be subject to road vibration, dirt, temperature variations. The control electronics might be vulnerable, but this stuff has been out in applications for enough time to have something of a track record. The ICE, even if new is going to be used in the Cruze and something else, so we should be OK there.
 

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My question is; is this 300,000 miles on one pack, or 300,000 miles cumulatively on several packs? In other words, is this just six packs going 50,000 miles each?
LOL What kind of research would that be?!?
(it's a cumulative cycle/mile study)
I assure you that it is for NUMEROUS packs going 300K EACH!
WopOnTour
 

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probably

If it is 300k miles per pack it would explain why they're now saying the volt will cost in the low $30's. Not having to price in many warranty covered battery replacements will have that effect.
 

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My question is; is this 300,000 miles on one pack, or 300,000 miles cumulatively on several packs? In other words, is this just six packs going 50,000 miles each?
"50,000 cells have been built and tested and Wallace claims that there has not been a single cell failure to date in either cell level, module level or pack level evaluations. In the lab, the packs have accumulated over 300,000 miles"

50,000 cells

packs = 300,000 miles.

How many cells to a pack? Then it is easy to assess the pack.
 

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Cells in packs

There are 220 cells in one pack. That, however, says nothing about how many packs have been tested. We know that 350 full packs have been built. At least 80 of these were built into the Integration Validation (IV) vehicles. Presumably most of the rest have been used in testing. Also new battery packs are currently being manufactured in the plant in Brownstown Township (south of Detroit). That may be where many of the 50,000 are as well.
After doing some math, 50,000 cells is only 225 packs. I'm guessing that the 350 packs that GM had were supplied fully built by CPI and the 50,000 cells were in addition to the 350 packs.
 

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There are 220 cells in one pack. That, however, says nothing about how many packs have been tested. We know that 350 full packs have been built. At least 80 of these were built into the Integration Validation (IV) vehicles. Presumably most of the rest have been used in testing. Also new battery packs are currently being manufactured in the plant in Brownstown Township (south of Detroit). That may be where many of the 50,000 are as well.
After doing some math, 50,000 cells is only 225 packs. I'm guessing that the 350 packs that GM had were supplied fully built by CPI and the 50,000 cells were in addition to the 350 packs.
I may be wrong, 50,000 / 220 = 227, so 227 packs.
300,000 / 227 = 1322 hours each pack.

So, divide by 365 (year) = 3.62 hours running per day in one year.

Not a lot of testing.

3.62 hours a day averaging 30 mph = 108.6 miles a day. Which is 39369 mile a year. Which is far too much as the average is around 10,000 mile. So 4 years testing.

Not a lot.
 

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I may be wrong, 50,000 / 220 = 227, so 227 packs.
300,000 / 227 = 1322 hours each pack.

So, divide by 365 (year) = 3.62 hours running per day in one year.

Not a lot of testing.

3.62 hours a day averaging 30 mph = 108.6 miles a day. Which is 39369 mile a year. Which is far too much as the average is around 10,000 mile. So 4 years testing.

Not a lot.
What's up with your math?
It's 300,000 MILES!
(or more correctly the same number charge>discharge and associated temperature cycles that would have accumulated over 300,000 miles.)

Just how does 300,000 MILES / 227 packs = 1322 hours????????

WOT
 

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Yes, 300,000 miles/ 10miles/year = 30 years. I'm guessing you're not a math major. :) GM hasn't been shouting their battery testing results from the roof tops, they have in fact spent A LOT of time and money to test hundreds of packs, some night and day at accelerated rates.
 

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What's up with your math?
It's 300,000 MILES!
(or more correctly the same number charge>discharge and associated temperature cycles that would have accumulated over 300,000 miles.)

Just how does 300,000 MILES / 227 packs = 1322 hours????????

WOT
Oh miles. I rushed and misread that.

50,000 / 220 = 227, so 227 packs.
300,000 (miles) / 227 = 1322 miles each pack.

So, divide by 365 (year) = 3.62 miles running per day in one year.

Not a lot of testing.

3.62 miles a day

Not a lot. Even worse.
 

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Yes, 300,000 miles/ 10miles/year = 30 years. I'm guessing you're not a math major. :) GM hasn't been shouting their battery testing results from the roof tops, they have in fact spent A LOT of time and money to test hundreds of packs, some night and day at accelerated rates.
My maths are OK it seems. It is interpreting their figures. What do you get?
 

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Oh miles. I rushed and misread that.

50,000 / 220 = 227, so 227 packs.
300,000 (miles) / 227 = 1322 miles each pack.

So, divide by 365 (year) = 3.62 miles running per day in one year.

Not a lot of testing.

3.62 miles a day

Not a lot. Even worse.
What part of 300,000 miles PER PACK dont you understand??
That's for whatever number of packs they had participating in the study (NOT cumulative across 227 packs)
OMG
 

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What part of 300,000 miles PER PACK dont you understand??
That's for whatever number of packs they had participating in the study (NOT cumulative across 227 packs)
OMG
Someone said that it was for all cells, that is what I understood.

If that 300,000 miles is per pack, then 300,000/10,000 (ave per year) = 30 years. If that is true that is impressive. What is the guarantee for the batteries?
 

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Someone said that it was for all cells, that is what I understood.

If that 300,000 miles is per pack, then 300,000/10,000 (ave per year) = 30 years. If that is true that is impressive. What is the guarantee for the batteries?
No problem. AFAIK the batteries participating in the accelerated mileage tests have been running pretty much 24-7-365 for over 2 1/2 years.However there is a "time" element with respect to the LiOn chemistry dgradation, so I for one would be surprised if a battery lasted 30 years.

So to answer your other question I can quote GM's Program Director for the Volt, Jon Lauckner as follows:

" the Volt battery is being designed for 10 years and 150,000 miles. That means the battery pack will continue to deliver 40 miles of pure electric range (EPA city or highway cycles) and will be fully functional (free from defects). So, both of these conditions have to be met for us to meet this requirement. Btw, even after 10 years or 150,000 miles, the battery pack will still have enough energy storage capability for non-automotive, stationary applications."

GM hasnt offcially announced the warranty on the Volt's battery just yet, but it's pretty clear from the statement above what they are shooting for. I do know GMs current 2-Mode hybrids (using the same Panasonic prismatic NiMh modules as the Prius) are warrantied for 8-years 100,000 miles.

HTH
WOT
 

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I can see in few years time when hybrid battery sets become finished for auto use and new usages in the home will emerge - maybe PV cell on the roof. After market PV cell frames in the back garden. Or will they do an exchange deal? Usages in small scooters?

I would like to see more real world and lab testing of the new Toshiba battery. This look good, very good. These batteries coupled with supercapacitors can really make in impact.

The great thing about EVs and hybrids is that when the existing battery set fade in 12+ years time the replacements will transform the car, as the newer batteries (supercapacitors) will be far superior to what is available right now.

Replacement costs should be no more than what a replacement transmission costs now. Replacing a transmission only keeps car as it was . A new battery set transforms the car.
 
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