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Front page of Jalopnik this morning: Tesla Motors Devastating Design Problem

If this becomes front page news on mainstream media websites or Fox picks it up, it's bad news for all cars that use electricity. I know the Volt doesn't have this problem but the news media paints with a very wide brush and I'm afraid this will be another, "Electric cars aren't ready for prime-time" story.

This is a big heaping bowl of, "Not Good."
 

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I agree that this is a problem and we must do damage control.
As they start whining about EVs, remind folks that ALL new technologies have bugs to work through. And people have to learn the limitations and workarounds.

There were experimental NUCLEAR AIRCRAFT at one point before we realized the enormous amount of shielding required for a nuclear reactor made it impractical to get a plane off the ground. I even read of a death (a century ago) of a woman using a GASOLINE POWERED CLOTHES IRON. It may seem ludicrous now, but people must go through a learning curve.

Remind folks that they should be happy this stuff isn’t swept under the rug, so that INEVITABLE solutions are found. And remind them that THIS is why tax credits are necessary- so early adopters have incentive to take the plunge. While this puts a black mark on EVs in general, we can point out that (I believe, by now) there are more Volts on the road than Teslas and no bricks are reported…and not one battery induced fire either (compared to tens of thousands of gasoline auto fires every month).
 

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The Volt keeps its charge when unplugged and uses a standard 12 volt battery to start the vehicle. When the battery is "used up" during a drive, the gas generator keeps the Volt running while the battery stays above a safe 30% SOC. Perfect engineering design.

The problem is how Tesla uses the main battery to maintain the battery pack at the proper temperature during hot or cold conditions while parked. What would make sense is for Tesla to stop maintaining the battery at 30% SOC while parked and prevent total battery loss. Having the vehicle "call" Tesla during low SOC while parked could allow them to contact the owner and warn them of the problem or take immediate action before loss. Better to have the car towed to get the battery charged than to tow for a battery replacement.
 

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After having read the article, i have to say that it is a big, steaming, heaping, pungent, and odorific pile of the most unattractive unfortunateness available today. and I can't think of a solution-- any battery will die over time, and advanced batteries(like, say, the LiPo in my RC vehicles) simply can't be run down to zero. The only thing that makes any sense would be to have the system shut itself completely down once the batteries get to a certain SOC, thus extending the life of the battery to something reasonable.
 

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This is a design flaw, not a battery problem per se. The design should take into account that the battery absolutely cannot go to zero charge.

Even my battery-electric drill goes 'dead' well before the battery (Li-Ion) is completely discharged. Cell phones and laptops also shut down well before the battery is discharged to zero.
 

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Sure, it's a design flaw, and one that might not be hard to fix, even retrofit. Leaving any car for months is dumb, actually, they all have problems if you do that, or at least, all mine have.

But - and I think this is what's important here - a car with near zero market share (which, depending on how defined, includes the Volt) getting all this negative attention means something else is going on, as normally such low-sales things are pretty much ignored.

I've seen and traced back some very vicious astro-turfing by oil interests in other areas, and for them, this is a lunch money investment to protect a much larger one that is difficult to shift out of. It would be reasonable to assume this is the same machine operating, since most people, certainly not the mainstream news customers - really care about what happens to a rich guy's car, and for what it's worth, that's us - no one else is buying expensive cars right now. In Chevies, its Cruzes that are flying off the lots, ask any dealer.

When was the last time you heard about some serious flaw in a Rolls or Bentley - or for that matter, a Jag or Ferrari? You don't - they happen but it's not news because it doesn't affect many people, and it's assumed they can handle it anyway.

No, you hear about it when a Toyota crashes from a jammed pedal...because they're all over the place and MSM customers own them. This is something very different going on these days.
 

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It's actually a flaw in design

The Leaf uses a 12 volt auxiliary battery to keep the electronics alive when the car is parked and powered down. Just like the Volt does. For both, the auxiliary can drain down, requiring a jump start or a tow, but the traction battery does not have any power draw on it when the car is off and parked.

Apparently Tesla did not do the same, but powers the standby items from traction battery's putting it at risk of severe drainage. They did not even put in a safety sensor to disconnect the battery at something reasonable like 20% SOC.

I smell class action lawsuit if that is true. Or am I misunderstanding their engineering?
 

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Your correct and that's the issue, there should be a high voltage disconnect that can be commanded off not only by the SOC software, but by an owner that wishes to store the vehicle ( like over seas shipments ) with the flip of a switch
 

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Your correct and that's the issue, there should be a high voltage disconnect that can be commanded off not only by the SOC software, but by an owner that wishes to store the vehicle ( like over seas shipments ) with the flip of a switch
I don't know much about the Tesla's electronics. If you needed to do this to a Volt for some reason, you could always pull the MSD in the center console. It completely isolates the traction battery...

(But as discussed above, I believe the Volt already has protections in place for the problem Tesla seems to be facing.)
 

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This is a marketing opportunity for the Volt me thinks! I think the Volt could easily be software upgraded to at least warn you that your battery is at 29%, etc. and give you the option to turn the generator on, or shut itself off if you have no other option.
I expected more of us on the forum to discuss the issue at hand rather than point the obvious finger. Sure the timeliness is fishy, but that doesn't mean that a $40k battery swap isn't a real problem.
Like I say, this is an opportunity for GM to show how easily and affordable the Volt battery is to swap compared to other cars. I'm guessing here, but I'm thinking the Volt battery pack is the cheapest and easiest to replace, even considering the temp mgt systems and all.
Can someone here speak to the complexity and time involvement required with swapping a battery pack in the Leaf, Karma, Focus or Tesla's??
at least in regards to Tesla, it seems to be a very complicated task. There is no way that these common laptop batteries are the major contributing factor in the 40k+ price tag!!! However, I also find it hard to believe that labor for any automotive job exceed 20k? Now I'm just confused?! How many freaking hours does it take to replace these 1680 cells?
The Tesla website states "The Tesla Roadster battery pack is comprised of about 6800 of these 18650 cells, and the entire
pack has a mass of about 450kg. "
huh?
 

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That sure sounds like a bad design to me. It should never let itself die. At 5% or 10% SOC, it should shut itself down completely. O

And it is even worse that it is not mentioned in the owners manual! When the main component of the drive train can fail from something as simple as this, it should be on the first page of the manual and in a very large font!!!

But in all fairness, what does it really say about anything like this in the Volt manual?

In the Section 10 - Vehicle Care, page 10-25, it talks about disconnection of the 12V battery for Extended Storage, but never really defines what "Extended Storage" means. Is leaving the car when it was in CS mode at the airport for two weeks going to be a problem? I don't really know. They do say to have the high voltage battery at "1/2 charge or less" and to store at temps between 14 and 95 degrees for storage. So maybe it would be a good idea to drive to the airport in mountain mode, so that it has kept a good bit of charge in the pack, before leaving it sit for a week or two.

Does anyone really know for sure about this?

Would be good info to have, IMHO

C-5277 - Proudly Purchased 0n 10-04-2011 In Youngstown, OH
 

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That sure sounds like a bad design to me. It should never let itself die. At 5% or 10% SOC, it should shut itself down completely. O

And it is even worse that it is not mentioned in the owners manual! When the main component of the drive train can fail from something as simple as this, it should be on the first page of the manual and in a very large font!!!

But in all fairness, what does it really say about anything like this in the Volt manual?

In the Section 10 - Vehicle Care, page 10-25, it talks about disconnection of the 12V battery for Extended Storage, but never really defines what "Extended Storage" means. Is leaving the car when it was in CS mode at the airport for two weeks going to be a problem? I don't really know. They do say to have the high voltage battery at "1/2 charge or less" and to store at temps between 14 and 95 degrees for storage. So maybe it would be a good idea to drive to the airport in mountain mode, so that it has kept a good bit of charge in the pack, before leaving it sit for a week or two.

Does anyone really know for sure about this?

Would be good info to have, IMHO

C-5277 - Proudly Purchased 0n 10-04-2011 In Youngstown, OH
I haven't tried parking it and walking away with CS range battery (22% absolute SoC) for more than a couple days. However, the Volt's architecture makes it unlikely to be an issue. The Volt HV battery is isolated from the rest of the car... There are only two ways to connect to it.

The main contactor is only enabled when the car is on, and connects the big wires to the power electronics module to move the car.

The other connection to the HV battery is the "multifunction" contactor, which is much smaller. This is the one energized by the charger to charge the car, and also where APM power and HVAC power come out. The software apparently does allow the car to energize this and run the TMS when parked unplugged at high temperatures and high states of charge, but the owner's manual claims this will stop at around 50% SoC (I don't think anyone on the forum has tried it.)

The only ways completely discharge the traction battery while off would be for this code to somehow lock the multifunction contactor on and keep drawing power for the TMS, or by self-discharge, which on Lithium generally takes roughly forever.

Volts get stranded by having the 12V battery die instead - but then, that can be addressed by a simple jump start (and so far has only happened in cases with a bluetooth glitch that we know of.)
 

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This is 100% a Telsa screw up, as other have posted, the Volt disconnects the battery pack when the car is turned off. Once disconnected, you can go YEARS without worrying about the battery, lithium has the lowest self-discharge of any technology, 2-3% per month, so If the battery at zero on the display, it would take almost a year to be an issue, if charged, you could go 4-5 years

http://en.wikipedia.org/wiki/Self-discharge

This isn't the Oil company's or EV haters, its a real design F&^kup by Tesla, and there inexperience is really showing in not realizing the messed up and not support the owners of the 100K vehicles. This is what happens when you buy from a start-up
 

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Does the Tesla really not have a 12V battery? Strange design. Any modern hybrid/EV has a 12V battery and a high voltage pack. The high voltage pack has contactors that open when the vehicle is not in use so no current can be drawn from the HV pack. Bad design if Tesla runs the vehicle electronics off the HV pack even when the vehicle is off. Are the model S and X the same way? I am a big Tesla fan. Hope they changed this with the S and X.
 

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you can bet that this is what they are doing this week --> Redesigning a 12V battery into the car. Or, maybe they are figuring out how to isolate enough cells to power the car up, and disconnect the rest. I am betting on launch delays for the Model S.
Damn you Oil companies for finding the dirt and flinging it! I really do hate them.
 

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you can bet that this is what they are doing this week --> Redesigning a 12V battery into the car.
It has one. Or possibly two on some cars if I'm reading this right There are apparently two separate 12V buses on the Roadster, one for general accessories and a second one for critical systems. It apparently also has a DC-DC converter running off of the traction battery that is always on for the critical systems:

http://www.teslamotorsclub.com/show...t-accessories/page4?highlight=Dc-DC+converter

That's how they end up with the long term self-discharge. The Volt's APM doesn't run unless the car is on, so it won't do the same thing (prolonged absences or power can drain the 12V battery, instead of the HV battery.)
 

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Source of Info?

The Leaf uses a 12 volt auxiliary battery to keep the electronics alive when the car is parked and powered down. Just like the Volt does. For both, the auxiliary can drain down, requiring a jump start or a tow, but the traction battery does not have any power draw on it when the car is off and parked.

Apparently Tesla did not do the same, but powers the standby items from traction battery's putting it at risk of severe drainage. They did not even put in a safety sensor to disconnect the battery at something reasonable like 20% SOC.

I smell class action lawsuit if that is true. Or am I misunderstanding their engineering?
I am curious how you know that the "always on" systems are strictly powered by the 12 volt battery and that the traction battery has no drain when the car is off?
 
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