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Discussion Starter #1
Hello all,

I've just read an article in EV World about Tesla's Roadster BRICK problem ... meaning that if you leave it unplugged for a long period of time, the batteries get totally discharged and get totally dead. The only solution is to replace the batteries at a cost of 40 000$ and NOT covered by Tesla's warranty. Apparently, even the Model S will have this risk.

Could a similar situation happen to a VOLT? Did it happen to a VOLT OWNER? Tesla_roadster-red.jpg
 

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The good thing about the Volt is that even when "empty" there is a 20% charge in the battery. Now a good question is how long will it take to drain that 20% by sitting unconnected? Would the Volt make the ICE start at some point to keep it from going to 0%?
 

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The Volt's design, in a package at 2/3 to 1/2 the price of a Model-S, does guard against that.

And if it does happen, the battery is replaceable at what is said to be approximately $3000. Tesla, a bit more :)

The linked article is more of a hit-piece against Tesla, but if the bricked Roadsters are true and the same battery management is in place for the Model-S - keep them Teslas charged up.
 

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Well the battery has its warranty and I suppose it is possible to brick one. I didn't see anything in the manual suggesting a time that the car must hit a charger. But if it were me I would have it attached as much as possible. Especially here in AZ where I do know that the battery takes a conditioning run every 3-4 hours in the mid summer heat.
 

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Discussion Starter #5

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The Volt's design, in a package at 2/3 to 1/2 the price of a Model-S, does guard against that.

And if it does happen, the battery is replaceable at what is said to be approximately $3000. Tesla, a bit more :)

The linked article is more of a hit-piece against Tesla, but if the bricked Roadsters are true and the same battery management is in place for the Model-S - keep them Teslas charged up.
Guards against it how? $3000 plus unknown labor rate.

"Hit piece against Tesla?" I disagree, given what is at stake I think the piece is fairly written. And is bringing to attention something that many owners may not be aware of.
 

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Some of the quotes culled from the understatement.com orginal post, and a link to the original post.

http://fordfocuselectric.com/forums/viewtopic.php?f=9&t=1129

This is a very big deal, and I am sorry to see this happening to Tesla. They are probably the reason we have Leafs and Volts to drive around

Would like to know if there are any scenarios under which this could happen to the Leaf or the Volt.
 

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At least guards against it through warranty (article notes that Tesla does not warrant against this). But possibly Pete Foss can say whether the Volt has logic in the computer to break the main battery link if charge reaches too low. I have to assume they have some type of guard in that way - otherwise, warranty claims may occur if someone leaves the Volt sitting for say 6-months. They do say to "keep the Volt plugged in when not driving" - maybe that indicates there are vampire draws worth considering.

Owners of roadsters may not be aware - but if the Model-S comes out with the same bricking-potential, that can be a big issue on sales and their stock price. I consider it a hit piece because this is more of a Tesla company issue that should be traded between the company and their car owners. If they have not told customers of this potential of bricking their cars - then maybe they should feel the heat of the article. Since the battery is the "life" of the car and you just can't bring a Li-Poly battery up from a dead state - then Tesla forgot to guard against this issue in their design and should try to handle this before building and shipping the Model-S and Model-X.

This is "worse" to me than the Volt's battery fire issue. And just in time to be in the news as Tesla starts shipping the Model-S later this spring. This is "Rush Limbaugh fodder" in that he can say "see, you can't even let an EV sit in the garage for a while without it failing and costing you $25K...EVs make no sense"

Tesla owners now can have range-anxiety *and* plug anxiety.
 

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No link and your blog didn't (seem) to expand on your discussion. How long do the batteries have to sit for this phenomenon to occur?
Edit: someone else posted the link; thanks
 

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The article reads that the car is always on, that in 7 days it can 100% discharge the battery. If true, that is a design issue. Volts can sit for weeks on the lot and have no issues not being plugged in, now this is a single article, but if true, its a serious flaw, one I'm not really surprised that a new small upstart would have made. There IS a reason I bought from GM, they have 100 years of experience building cars, Tesla, not so much
 

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Discussion Starter #12
This «Brick» issue worries me, especially that I'm considering the Model S as our second EV car. Here in Quebec we have cold temperature (on certain winters we can get -30°F). I'm doing my best to keep my Volt plugged in ... but sometimes it's out of your control ... What if we get a power outage during a cold night ??

What worries me is that there is no warranty covering it and no insurance ... with the Tesla case. If I were Tesla, I would at least make a partnership with an insurance company that covers this issue even though there is an extra yearly cost ...

Now I want to know if it's covered with the warranty included in the Volt ... if not, what would be the price for replacing the battery pack? At least with the Volt, you can remotely start the ICE with the smartphone app ...

Sly
 

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This article seems to raise as many questions as it answers. But if the basic premise is true, then it's quite shocking.

What has me confused is the fact that the solution to this problem seems so easy: Just cut off any loads on the battery once the pack (or cell) voltage drops below a certain threshold. I thought this was how all EV's worked(?). Then, you might have to tow the car somewhere to recharge it, but you wouldn't have permanent damage to the battery. (Lithium battery chemistries self-discharge very slowly, so I believe this must be due to external loads and not self-discharge.)

Page 5-2 of the manual states:
"When fully charged, the Battery’s charge level can drop as much as 7% a day and 50% within the first week. When the Battery’s charge level falls below 50%, the rate of decline slows down to approximately 5% per week."

What would be causing a 50% drop in charge in one week??? I guess the answer must be heating or cooling of the battery pack in cold or hot ambient temps. Then, when the SOC drops below 50%, thermal management is abandoned, I guess.

As for the 5% per week figure thereafter... with a ~53 kwh battery in the roadster, that equates to 2.65 kwh/week, or a constant loss of 16 watts. That seems a bit high, but maybe not unreasonable.

And what's the deal with the stuff about an "extension cord that's too long"? I'm not an EE, but that seems like complete BS to me.

Either way, Tesla will have to respond to these allegations.
 

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How funny... (in the eyes of a non-Tesla owner of course!) Just for the record, just about every device with a rechargeable battery says you should recharge it in regular intervals if not in use. For instance, in the manual of the Peg-Perego Corral T-Rex, basically an electric quad for children, it says to recharge the battery every 3 months if not in use. That's definitively longer than it takes the Tesla to become a brick, but the Peg-Perego vehicles also have no parasitic loads whatsoever. And that's using a lead-acid battery... now, the Volt has a lithium battery, which is said to only lose 5-10% of its capacity per month, so it should take at least a year until a fully charged battery gets flat. What's more likely to happen, in my opinion, is that the 12V battery will be drained by parasitic loads over time, because that's actually the battery that's active even when the Volt's turned off and powers all the monitoring systems. I think in the Volt, the high-voltage battery is only engaged either when charging or operating the heater, or when the car is powered on, but there's no parasitic load on it when it's not engaged, so while you may lose your 12V battery due to deplation, it won't be as easy to kill the big, expensive dry battery. And even the 12V battery will take a few complete discharges before it's unable to be recharged instead of only a single one, and it's fairly inexpensive to replace.

So... while a Volt may become a brick, it can be un-bricked by jump-starting it or, if it really happens multiple times, replacing the 12V battery. I think that's the safeguard here. I think it pays off to have a car developed by a reputable car company, not a newbie like Tesla is.

By the way, the first Prius's had a similar problem... in EV mode, you could run the NiMh battery completely flat, killing it.
 

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Of course, the media will forget the troubles IC cars had (maybe still have) with this one. I've had a few cars you couldn't let sit a week unless the battery was new - the computer and the clock would run them down just fine sitting in the driveway, and they didn't come with a plug, either. Buicks, Pontiacs, Olds - all had that problem here. I wouldn't know if my newer Chevys had the problem - after being bitten by that one with the used ones, I made sure they (and my Honda) are run enough to keep the batteries up, period. Heck, it's good for the whole car - sitting unused doesn't do anything any favors.

I'd note that even in Tesla's case, we're talking weeks here - it's a shameful waste of electricity, but anyone who has more cars than they can get driven in weeks is probably a fairly special case - rich collector? Poor because they bought too many cars?
Not your average user, I'd think. Of course, the media will ignore that too.
 

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By the way, the first Prius's had a similar problem... in EV mode, you could run the NiMh battery completely flat, killing it.
Huh? I've owned a 2001 Prius for 11.5 years and have never heard of this alleged problem. Does this scenario involve running out of gasoline and then continuing to drive on the NiMh battery until the car stops moving....?
 

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Repost from another thread (because naysayers will jump on this headline):
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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I'm quite surprised DCFusor didn't think this is a design flaw, quick math puts the constant discharge at ~150watt ... that is s huge constant load.

I've been an engineer for 30+ years, this is a real f*&kup on Telsa's part. If the Volt had a constant 150 watt load, it would brick the Volt in a little over 2 days. This issue is when powered down, the load should be in the milliwatts range. EnegryStar appliances when off need to meet a maximum load of less than 1 watt and regular cars would need to be in the 1-2 watt range or would kill the starting battery a week, which they don't

Put it another way for the load, none techies might relate too, its like leaving the headlight on high beam 24/7

This is what happens when a team with no car experience designs a new car, its not unexpected and shows in a clear way why you need a Nissan or GM to build Electric or EREV vehicles, the start-ups don't have the Design quality control to make sure stupid things don't get into production cars. All that the Tesla CEO was concerned about was getting cars out the door as was shown in the movie, revenge of the electric car
 

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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.

One major issue is how some public charge stations may disconnect when the battery is fully charged. Tesla's charge cord most likely overcomes this problem, but how many Model S owners might use the J1772 adapter thinking that they are safely leaving the vehicle at the airport for a couple of weeks. Better to leave the car connected at home and take the airport limo. Saves airport parking fees too.
 

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I'm quite surprised DCFusor didn't think this is a design flaw, quick math puts the constant discharge at ~150watt ... that is s huge constant load.

I've been an engineer for 30+ years, this is a real f*&kup on Telsa's part. If the Volt had a constant 150 watt load, it would brick the Volt in a little over 2 days. This issue is when powered down, the load should be in the milliwatts range. EnegryStar appliances when off need to meet a maximum load of less than 1 watt and regular cars would need to be in the 1-2 watt range or would kill the starting battery a week, which they don't

Put it another way for the load, none techies might relate too, its like leaving the headlight on high beam 24/7

This is what happens when a team with no car experience designs a new car, its not unexpected and shows in a clear way why you need a Nissan or GM to build Electric or EREV vehicles, the start-ups don't have the Design quality control to make sure stupid things don't get into production cars. All that the Tesla CEO was concerned about was getting cars out the door as was shown in the movie, revenge of the electric car

Pretty sure the roadster uses an active cooling system (TMS) to protect its laptop batteries (which are very sensitive to heat). Circulating a liquid could easily be the 150w load.
Maybe that's why when its hot the volt will only use TMS until the battery reaches a particular level (45% or something if I recall) but then stop protecting it.
 
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