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Tesla Model S Battery Drain Issue Fixed
cartechboy writes "Does the Tesla Model S suck down power even when the car is switched off? Recently, a tweet to Elon Musk with an article saying so sparked the Tesla CEO's attention. He tweeted that it wasn't right and that he'd look into the situation. Then a few hours later, he tweeted that the issue had to do with a bad 12-volt battery. Turns out Tesla had already called the owner of the affected car and sent a service tech to his house to replace that battery — and also install a newer build of the car's software. Now it appears the 'Vampire Draw' has been slain. The car went from using 4.5 kWh per day while turned off to a mere 1.1 kWh. So, it seems to be solved, but Tesla may either need to fix some software, or start sending a few new 12-volt batteries out to the folks still experiencing the issue."
..for Elon's next Slashvertisment.
The learning curve gets climbed.
Laughter is the Spackle of the Soul.
The 12V battery of a family member's Honda Civic didn't just draw more current than intended. It failed completely! The car could not start! The whole battery had to be replaced at cost to the owner and the Honda CEO was nowhere to be seen.
I should use this sig to advertise my book ISBN-13 : 978-1501515132.
Can't they put a big red cutoff switch for the battery, for owners who won't be charging to just physically disconnect the battery when they're parked?
If I had one, I wouldn't need the computer/GPS/3G_app/dataminer to keep running when I'm grocery shopping or working, as long as it reboots in less than, say, a minute.
Do that are you're down to the raw battery leakage only.
That's 45 watts continuously, it should be more like 10. Multiply the wasted energy times tens or hundreds of thousands of cars and all of sudden you're talking about the output of an energy plant wasted every day.
The whole battery had to be replaced at cost to the owner and the Honda CEO was nowhere to be seen.
This would be because people will buy a Honda regardless of whether the dealer or company or CEO is a prick or not, where Tesla is trying to get itself a foothold in the market and Elon feels personally responsible if there's a defective product because it reflects badly upon the company. A hundred million Hondas Thousands of Teslas.
Laughter is the Spackle of the Soul.
1.1 kWh is a hell of a lot energy. Something is still seriously wrong if it's not lost in balancing the battery pack.
Some pretty fantastic customer care tbh
That's still 46W permanently, isn't it? More than most devices. Is that really what's needed to keep the batteries charged?
Batteries discharge when doing nothing. What if the 1.1kWh is the normal for just sitting there like if it wasn't even in the car, plus some trickle for things like the clock and other persistant items? This might say more about the batteries' charge decay rate than the rest of the system causing a drain (though I do figure, fairly, there's a little more than just the clock and expected no-load decay at issue here).
Laughter is the Spackle of the Soul.
I'm sure Tussle owners can manage the expense for awhile, eh?
Huh? 4.5 kilo watts per hour per day?
How much electricity does a fossil-fuel vehicle use in a day while sitting, turned off?
If it's anywhere near 1.1 kWh, then yea, no big deal for the Tesla to have a similar draw.
An enigma, wrapped in a riddle, shrouded in bacon and cheese
There's a 12-volt lead-acid battery in the thing to power the auxiliary systems. It's the same size as a regular automotive battery, but apparently is a sealed type, intended to last the life of the vehicle. Since it doesn't need to provide cranking power, a high-current battery isn't necessary.
Tesla owners have been reporting 12 volt battery failures for months. Usually the charging system reports "12 volt battery failure", but apparently a partial failure is possible, where the aux battery is an energy drain but still functional.
For a $100,000 car sold by some Ian Flemming villain, I expect the damn thing to be giving back more than 1.1 KW just sitting in my driveway. And v2.0 better be able to hover.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
and it will be billed at dealer rates.
Before the battery replacement, the car lost 3.5kWh/day. After the replacement, it lost 1.1kWh/day. That's a difference of 2.4kWh/day, which is 100W. That's something like 8 Amps internally leaking in the 12V battery. That seems shockingly high. Or maybe there's something else going on. If the battery was marginal, then perhaps the car's DC-DC converter was continually "charging" it but actually overcharging it. Then it would be electrolyzing 8A worth of water and battery acid. I expect that would make a giant mess. Alternatively, it just keeps running the DC-DC converter at very low output. The DC-DC converter could be incredibly inefficient when producing just a little bit of current (Tesla is reputed to use a huge (~200A) DC-DC converter, so the thing could be running at about 1% of rated output at, say, 10% efficiency).
A standard automobile uses minimal electricity. The need to maintain power to the clock, a trickle to maintain memory for the radio presets, and keep the keyless entry system listening for the activation code. These things take a tiny amount of electricity. Approximate usage when ignition is off is ~500mA . This equates to 0.144kWh per day!
Tesla's "fixed' consumption of 1.1kWh per day is an outrageous 8 times higher in comparison. But, they are also keeping their computer up and running all the time in order to maintain cloud connection for monitoring, updates, remote access...
"According to Tesla, the car needs a constant flow of power to keep its computers and systems switched on 24/7, ready to boot up instantly when the driver gets into the car. (It's a popular myth among Model S owners that much of the vampire power goes to keep the battery warm during cold nights. This is simply not true.) According to Tesla, there is no thermal management of the Model S battery when the car is turned off and not charging--no matter how cold it gets."
"Ironically, the Model S had very little vampire drain when it was first introduced. My owner's manual is based on the original software in the car. "When you're not driving Model S, the Battery discharges very slowly to power the onboard electronics," it purrs reassuringly. "On average the battery discharges at a rate of 1 percent per day. Unfortunately, the "sleep mode" software in those early cars triggered all sorts of glitches in the car's other systems. Eventually, the problems became so persistent that Tesla simply disabled the sleep mode. With sleep taken away, the vampires came out to play. And instead of draining 1 percent every 24 hours, the Model S battery suddenly began losing 5 or 6 percent of its charge every day. (In the case of 60-kWh cars like mine, it's closer to 7 or 8 percent.)"
"So far I've run three overnight tests with the kWh meter. For each test, I charged the car up in the evening to its usual selected level (In my case, about 80 percent). Then I removed the charge plug. I allowed the car to sit unplugged overnight and on into the next day, until I needed to drive it. (Typically a span of 12 to 24 hours.) Before driving it, I plugged it back in to top off the vampire-depleted battery back to its original level. Then I checked the kWh-meter. Test results: The three tests showed vampire losses of 2.3 kWh in 17 hours, 1.9 kWh in 23 hours, and 4.2 kWh in 18 hours. Total vampire power lost was 8.4 kWh in 58 hours. That's an average of 3.5 kWh per day--roughly 25 percent lower than the losses I measured previously. I can't explain the wide variation in the vampire draw over the three tests. Clearly, more than three tests will be required to come up with an accurate figure. But it's clear to me that the new vampire-slayer software is pretty weak stuff. It's better than nothing, I suppose. A 25-percent improvement means that the 20,000 Model S cars now on the road will only waste about 70 megawatt-hours of power a day, down from 90 MWh. And it means that Musk's anti-vampire prediction has turned out to be one-quarter true in twice the time. Update 6.0, anyone?"
http://www.greencarreports.com/news/1088648_life-with-tesla-model-s-even-after-update-vampire-draw-remains
My god, one person's battery failed completely? That's truly shocking! I've never heard of a battery failing before.
That is clearly a worse problem than every single Tesla Model S ever made sucking down 4.5KWh per day, every day, for months on end while Tesla sit on their fingers and do nothing to fix a problem that can apparently be fixed within hours of a single Tweet to the CEO.
And the fact that the "fixed" Tesla still sucks up enough power to drain the battery in any other car overnight, every night, for the rest of recorded time -- well, that's just the price of having a shiny car with no doorhandles or keys, right? Pretty trumps energy efficient and intelligently designed every time!
Say you take this to the airport and go away for a week or two? Will there be any juice left to run the car? I think most people need a car that doesn't need so much pampering every night.
The problem with the 12 volt battery is exactly what caused all the problems with the review car that John Broder wrote about. Hmm, I guess Broder might not have been the big liar that Musk and his gang of fanboys painted him out to be.
by Mike Buddha -- Someday the mountain might get him, but the law never will.
This is how other Tesla owners responded to what we now know was a legitimate complaint. I ask you, who are the real nut jobs?
Say you take this to the airport and go away for a week or two? Will there be any juice left to run the car?
Nope.
Then a few hours later, he tweeted that the issue had to do with a bad 12-volt battery. Turns out Tesla had already called the owner of the affected car and sent a service tech to his house to replace that battery — and also install a newer build of the car's software.
So, it seems to be solved, but Tesla may either need to fix some software, or start sending a few new 12-volt batteries out to the folks still experiencing the issue.
Well, just to be accurate here. As far as we know, the problem was tracked to be a bad battery. Thus it does not make sense to suggest that they "may need to some software". During servicing, the faulty car's software was possibly just upgraded "while we are at it", without the upgrade necessarily having to do anything with the battery.
What is the US energy mix? Is a Tesla better for the environment than a small petrol driven car? What about the embodied energy of a Tesla vs. a conventional car?
I know here in Australia where we burn brown bloody coal an electric car produces more emissions than a V6.
Sad but true.
I contacted Volvo but they didn't send a repair person out.
I can't believe it. I trusted Sweden and this is how I am repaid....
Damn you Sweden!!!!
I just replaced it with a, standard domestic brand, Ford Pinto.
Sounded like a great deal. We'll see how it goes.
Frick'n Sweden.....
In every piece concerning Tesla on slashdot, there are a few people making negative comments about Elon Musk. However, not once have I seen the complaints backed up with facts, examples, or otherwise, just negativity without any indication as to why.
Could someone please explaint to me why there is this hate on Elon Musk, and what it is about?
How much electricity does a fossil-fuel vehicle use in a day while sitting, turned off?
I recently had to troubleshoot something like this (turned out the culprit was a flaky switch in the trunk that would leave the trunk light on constantly). For a typical older-model car like mine, the expected current load is generally less than 30mA. A newer model car may be several times that, due to the increased parasitic draw from various built-in devices.
The incandescent bulb in my car's trunk drew several hundred milli-amps, which was enough to drain the battery within a day or two.
I haven't noticed the vampire battery drain but then again I always keep my car plugged in at night. I also had to get my 12v battery replaced some months back. The 12v battery manufacturer outsourced the batteries to a Chinese company that outsourced them to a Vietnamese company causing a bunch of cars to get crappy 12v batteries that tended to fail fairly rapidly. I found out about it when I went to install a software upgrade and the car complained that the 12v battery was going bad. It sounds like the cars were wasting a lot of energy trying to keep these crappy batteries charged up. Like the author, I was contacted by Tesla about getting the battery replaced. In my case though I had taken my car in for service a couple of days earlier to fix some minor rattles and they replaced the battery then.
The 12v battery is not easy to replace as far as I can tell. It's in the back under the frunk next to the firewall but underneath a lot of heavy reinforcing. It looks like the only way to replace it is to remove the plastic frunk lining. One advantage of its location is that it is very well protected in the case of an accident.
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Welcome to the world of cars which are not astoundingly expensive. The 2000+ Astro will drain the battery if you leave the keys in the ignition. Apparently, so will the 1992+ Ford F250, and it doesn't even have a BCM! Nobody was sending techs 'round for those problems, either.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
That you are not really into names?
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Ernest Hemingway
Regarding self-discharge: .01 / 30 = only 0.027 kwhr/day
Li-Ion has a self-discharge rate of about 1% per month. A Tesla S has an 85kwh battery pack. So, 85 *
Regarding the energy used by door locks and clocks:
An average car battery is about 40 amp-hours @ about 13v. (about 0.5 kwh total capacity) Yet, you can leave a car sitting for a couple months and it still has enough energy to start the car. But the Tesla would completely drain the same battery in a half-day.
So, for a car sitting in the garage doing nothing, 1.1 kwh/day wasted energy is much better than 4.5. But it is still embarrassing for a car that claims to be green.
..these are dollars well spent by the oil and auto industries... Elon Musk could be a huge ahole, but he would not come close to the galactic ahole quotient of the the oil and auto industries.
My Electric bike has a (pretty high for a 2 wheel electric vehicle) 2.5 KHW/hr battery. It's pretty much a several thousand dollar battery. To think the tesla is chewing through that every 2 days while *off* is disconcerting.
Let's convert how much energy is wasted in tesla's sleep mode compared to a fossil fuel car: According to yahoo answers, 1 gallon of gasoline = 34.7 kWh.
Energy consumed by a model s in a month = 30 x 1.1 = 33 kWh Converting 33 kWh to equivalent gallons of gasoline = 33 / 34.7 = 0.95 gallons
The tesla wastes the equivalent of 1 gallon gasoline/month while parked!
I hope Tesla keeps working on reducing the amount of energy wasted. But lets use those same numbers for cars that actually get driven and see how the Tesla compares:
Given the average US driver drives 13476 miles per year, which is 1123 miles per month. And the average new car gets 24.9 miles per gallon. Therefore the kWh equivalent for the average ICE car is: 1123/24.9*34.7 = 1564 kWh / month
Whereas the Tesla consumes 38 kWh/100 miles. So for the Tesla we have: 38/100 * 1123 = 427 kWh driving per month, plus 33 kWh wasted per month gives a grand total of 460 kWh / month.
In other words, for people that actually drive their cars, the Tesla uses less than 1/3 of the energy of an ICE. Which seems relevant to the conversation.
Now, to be fair. I bet that people drive their Teslas more aggressively and get less than the EPA 38 kWh/100 miles. And there is the drain of accessories, etc. But that is a lot of headroom, I doubt any of the similar sized ICEs ever come close to the Tesla in energy efficiency.
Some privacy policy Slashdot.
I wonder why all these Tesla owners with bad lead acid batteries aren't getting warning messages, saying that the lead battery is bad and is causing vampire losses?