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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."
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.
" to a mere 1.1 kWh per day, while doing nothing.."
- sorry, I am actually a Tesla fan (or would be, given the chance..) - but 1100w (per day) for doing sweet fuck all, presented as progress?
it's stuff like this that makes me say, thanks, call me when you have the finished article.
1.1kWh is equivalent to having a ~40W light bulb on. If you have a couple of circuits powered on, given it is a fully electric car with all kinds of gizmos built into it, this discharge rate is actually quite nominal.
Face your daemons!
Actually, it's shockingly high. I'm a Tesla fan, but this seriously makes me wonder what's eating up all that energy while the car is supposed to be "off".
The Tesla is not the only car out there with "all kinds of gizmos built into it": every high-end luxury car, from the likes of Mercedes, BMW, Cadillac, etc., is loaded with electronic accessories. However, all those cars run on gasoline engines, with a standard 12V battery to keep things alive when the car is "off". No regular car would be able to start its engine in the morning if it were powering a 40W light bulb all night.
So what exactly is the Tesla doing with all that power? Even if it's keeping a WiFi connection alive, that shouldn't take much power: my little smartphone can do that for days with a puny little 5.6Wh battery. Are they running the main computers at full power? It really shouldn't be that hard to put them into sleep states when the car is off. It sounds like maybe they badly architected the computers in this car, so that they could never go into power-saving sleep states and still keep the WiFi/3G connection alive, something every modern smartphone can do with ease.
Wan't to completely turn the battery off? You sure can, but that clicker to open/lock the door won't work, nor would the security alarm. These are the first two things that come to mind. There might be many other essential things that you might have to do without.
Face your daemons!
One of my favorite features of my Nissan Leaf is that I can turn the air conditioning or heater on from a phone app. I can also check the state of the batteries and the time remaining until it fully charges. So even in standby, electric cars are doing a decent amount of stuff.
"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
And the fact that the "fixed" Tesla still sucks up enough power to drain the battery in any other car overnight, every night...
I'm kind of wondering if "sucks up" is really the right verb to be using here. I mean, the article's author notes that the battery pack has a nominal 85 kWh capacity. Losing 1.1 kWh in 24 hours (note, not just "overnight") from a fully-charged battery pack is a shade less than 1.3% of the total capacity per day; if it maintained that rate of discharge, it would drain the battery pack in about 2.5 months.
The question I have, then, is how much of that consumption is replenishment of unavoidable self-discharge from the batteries, versus actual electricity used to power the various onboard electronics packages. That is, even if you physically cut every connection between the car and the battery pack in the evening, how much would the charge need to be topped up come morning?
~Idarubicin
But expecting to turn all the electronics OFF in a present day automobile is not the smartest of ideas.
For sure the clock would be wrong - and just flash 12:00 all damn day :-)
It must have been something you assimilated. . . .
Yes, but a mobile phone can't drive dual large displays with Nvidia GPUs
My phone drives a full HD (1920x1080) screen with desktop class graphics, more than enough for what Tesla does. They should be able to power down their GPU and screen when not in use.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
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?