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Why Tesla Cars Aren't Bricked By Failing Batteries
itwbennett writes "Don't believe recent claims made by a blogger that non-functioning batteries in the Tesla Roadster cause the electric cars to be bricked, says IDC analyst Sam Jaffe. 'Here's the primary fact that the blogger in question doesn't understand: the Tesla battery pack is not a battery,' says Jaffe. 'It's a collection of more than 8,000 individual batteries. Each of those cells is independently managed. So there's only two ways for the entire battery pack to fail. The first is if all 8,000 cells individually fail (highly unlikely except in the case of something catastrophic like a fire). The second failure mechanism is if the battery management system tells the pack to shut down because it has detected a dangerous situation, such as an extremely low depth of discharge. If that's the case, all that needs to be done is to tow the vehicle to a charger, recharge the batteries and then reboot the battery management system. This is the most likely explanation for the five 'bricks' that the blogger claims to have heard about.'"
There seems to be a fundamental misunderstanding of the terms 'battery' and 'cell'. A battery is the collection of cells. So a Tesla could be bricked by a failed battery but it is tolerant to a failure of individual cells. This is not surprising.
http://www.autoobserver.com/2011/02/towing-raises-new-issues-when-evs-are-involved.html
How about this: the $40K has been made up from whole cloth by a blogger we already know is ignorant of the facts surrounding electric cars.
Prediction for end of Universe #42: Fencepost error in Quantum_bogosort.cpp
Yes, the claim seems to be actually true: http://jalopnik.com/5887265/tesla-motors-devastating-design-problem
When not plugged in or when plugged in with an unsuitable extension cord, the battery can run completely dry within a few days (one claim say that the battery can go from full to 50% within a week, another claim on that website says that according to Tesla, one car went from 4% to dead in a week).
I guess most people who buy an electric car will say "well duh, I know that when I have my car not plugged in, eventually the battery will be empty. I'll just have to recharge then". But I guess also most people will not know that the battery will be DEAD, as in "you have to get a new one, this one's DESTROYED" when it goes to zero charge.
Having a battery which can be destroyed in a matter of days if the car is not plugged in is a pretty big issue. An issue people really need to be made more aware of. Go on holiday and leave your Tesla at home? You better ask a friend to check every couple days if the car is still charging. Or what if you park your Tesla at an airport, plan to leave it plugged in there for a week, but on the first day you're gone, some kid unplugs the car "for the lulz"?
This entire article is stupid. Essentially they are making the technical claim that the car isn't REALLY "bricked" because "Only one or two cells are really bad, and they can be fixed."
Here's the problem with that argument: If a handful of bad cells in a battery pack cause the pack to be unusable, AND the car to be un-tow-able AND require the ENTIRE PACK to be replaced at a very high cost, then for all intents and purposes the car IS "bricked".
Techno-sementic arguments about the precise definition of "bricked" don't matter AT ALL. The damn thing won't work anymore without paying an arm and a leg to have it shipped back to a tesla service center and have the ultra-expensive pack replaced. It's Bricked.
Ultimately this points to two issues:
1) Tesla's battery management system is woefully inadequate and hasn't gone through proper real-world testing. As the darling of EV lovers and large portions of the government they were given a pass (and large amounts of taxpayer money) and QC wasn't done properly.
2) ANY vehicle power system the requires a complete core unit replacement part by simply leaving the vehicle sitting unused for a "normal" amount of time in "normal" environmental conditions is NOT ready for prime-time. If this is the state of EV's across the market, and not just a tesla-specific issue, then EV's are in no way ready for the mass market. Niche market, yes, mass market, NO.
Hopefully this will turn out to be just a Tesla problem and they can get it fixed quickly.
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Some injection systems required multiple thousands of dollars of repair after being run dry. I know that's not quite the same amount, but those cars I know about cost less than $30k new...
Lesson: If you pay over $100k for something, learn the limitations it has. Expensive things require more maintenance, usually.
Two things are infinite: the universe and human stupidity, though I'm not yet sure about the universe. - A Einstein
Having RTFA'd, it is a negative opinion piece full of half truths and misinformation. That article is a horribly blatant attempt to discredit the vehicles from somebody who does not understand the underlying technologies. It needs to be taken as an opinion piece - there are zero references on his five examples (it's simply a chat with a service manager), and he is stating things as fact which simply aren't.
:P
First: yes, there are cases with batteries where they can be discharged to the point where the cells themselves are damaged and cannot be recharged. This is the case with *most* battery chemistries and is not going away any time soon. The blogger calls this a "Devastating design problem" when it is simply a part of the technology, like not storing your fuel cans near the furnace or leaving fuel to sit in a carburetor. There is a pretty clear warning in the car's manual not to let the battery voltage flatline for long, our intrepid blogger even provided a a PDF file with that page out of the manual. It states that the battery must be charged immediately if the charge level falls to 0% and has a great deal of information on the care and feeding of the battery.
Even if we take the five failed battery packs as truth, that is 0.2% of vehicles with an issue - an issue that in each example was due to the owner not charging the vehicle with one possible exception. His extension cord example could present a possible issue with the Tesla chargers. A typical cheap "heavy duty" extension cord will have 16 gauge wires, which over that distance is going to have some noticeable resistance. I don't know the current draw of the battery, but if it is expecting to pull 10 or 20 amps, the charger will see a significant voltage drop and likely cut off the charging (unless it has a "trickle charge" mode, dunno...). If the vehicle didn't report that it wasn't charging (or inaccurately reported it was), then I could see this being a design issue. I'll also note that this particular example did not state whether the customer had to pay for the repair.
What it comes down to is all electrical systems have ways they could be improved. That doesn't make this a devastating problem, it is simply an aspect of this class of vehicle that the owner needs to pay attention to. This blogger has a bone to pick or wants to stir the pot with a sensationalist report. Apparently it's working, after all, we both read his article
+1 Disagree