Why Tesla Cars Aren't Bricked By Failing Batteries 362
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.'"
battery vs cell (Score:5, Insightful)
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.
Re:battery vs cell (Score:5, Informative)
Remember: Bricked = Failed and unrepairable.
Re:battery vs cell (Score:5, Interesting)
Remember: Bricked = Failed and unrepairable.
This is a curious belief. I presume you've not been around embedded technology enough to have ever heard the term "unbrick", which is what people who actually understand the term "brick" used to describe the process of recovering from a bricked state.
According to your incorrect belief such a term could not possibly exist. And yet it does. So either the world is full of embedded engineers who don't know what they are talking about, or you are simply announcing to the world your own ignorance. Which is kind of useful: everyone here claiming that the Tesla is not "really" bricked by being left uncharged for a few months--as might easily happen to a vehicle in storage, being shipped somewhere, or simply parked near an airport during an extended vacation--is identifying themselves as having nothing useful or interesting to contribute to the conversation.
Likewise, people claiming that "this can't happen because power management" are declaring their ignorance of electrochemistry, which goes on regardless of external circuitry. Electrochemical cells that are not being actively charged can and do continue to discharge all by themselves regardless of anything any external circuit does. Some types of cell can and do get themselves into an unchargable state after sufficiently deep and prolonged discharge, regardless whether the discharge is passive or active.
So this "refutation" of the claims against Tesla is nothing but hand-waving anti-scientific bullshit: it is saying, "What has actually happened cannot possibly have happened according to my understanding, and my understanding cannot be wrong so the facts must be wrong." This is no different from the people who claimed that Galileo couldn't have seen the moons of Jupiter because just as there were seven seas and seven openings in the human skull so there could be only seven wandering stars.
There is a lot of this kind of anti-scientific reasoning about. I recently saw a claim that the Heartland Institute's campaign against second hand smoke laws was based on the "reasoning" that second hand smoke wouldn't be breathed deeply into the lungs and so couldn't cause lung cancer, regardless of the actual empirical data that shows second hand smoke causes lung cancer. This is not "reasoning" in any Bayesian sense: it is gibberish masquerading as thought.
The same kind of gibberish seems to be all that defenders of Tesla can come up with here. If anyone really believes they can't brick their Tesla by fulling discharging the battery they should drive it to the point of full discharge and let it sit for a while. That would give us new facts to account for, and actually contribute to the resolution of this question.
Re:battery vs cell (Score:5, Insightful)
which is why Tesla requires owners to shell out $40,000 to REPLACE a completely discharged battery.
It's bunk. If the battery pack is completely discharges, tow it to a charger, plug it in and wait. Then reset the battery management system, and you;re good to go.
What kind of cretin believes that a discharged rechargeable battery requires replacement?
Re:battery vs cell (Score:5, Insightful)
If Tesla actually built multi-kilodollar battery packs that allow their cells to run below safe discharge levels, somebody at Tesla needs a beating. If, however, this story is 'rechargable battery pack must be recharged and possibly recalibrated after running 'flat' as defined by the management circuit!', then the writer needs a beating.
Re:battery vs cell (Score:4, Informative)
Once the bank of cells does go below the detection level, it is still possible for them to still discharge further, depending on the condition. But they should wire the battery pack management system in such a way that it can be powered itself by other means than just the battery pack it manages. When the charge connection is plugged in, it should be made so that a low level of power is provided to bring the management system up without it being powered from the pack. At this point, it should be able to test the battery pack condition to determine if it can be charged back up safely or not. If Tesla didn't think of it, their bad.
Re: (Score:3)
I have a 2.0 Roadster; I will check tonight if the battery management system can have its power provided via an external source, with a relay system to switch between the two.
Warranties: They're made to be voided.
Re:battery vs cell (Score:5, Interesting)
Ever found an old cell phone in your night stand drawer or wherever? I recently found one from the early 90's (almost 20 years old) and the thing still had a 1/2 charge left and worked. Battery cells take forever to self-discharge and at that point there will probably be more damage to other parts of the car because it's been standing still so long (corrosion, plants growing in or through the body, rodents nesting and chewing through cables) that maybe you should just scrap the car.
Re: (Score:3)
Ever found an old cell phone in your night stand drawer or wherever? I recently found one from the early 90's (almost 20 years old) and the thing still had a 1/2 charge left and worked.
A 20 year old cell phone probably had a NiMH or NiCd battery.
NiMH and NiCd batteries can indeed last decades -- but they won't hold a charge (especially NiMH) for more than a few months. (The modern low self discharge NiMH cells are much better and can last a year or so, but if this is 20 years old, it's not one of those.
Li-ion and Lipo batteries will hold their charge for a year or so too -- but they wear out even if not used, and so they're usually dead (as in throw it away -- it won't accept a charge an
Re: (Score:3)
I found some time ago that rules of thumb are just a good way to be embarrassed by reality. What we believe can be trumped by facts. It's best not to believe too much dogma too implicitly.
Ever heard of the Sony Eneloop? It's a NiMH cell that holds 75% charge for three years and is completely unharmed by doing so.
I put aside a notebook with a LiIon ion battery for several years and recently turned it on and it booted and worked fine on battery. And it still accepts a full charge. That's on the original 2003
Re: (Score:3)
According to Michael Degusta (author of The Understatement blog), five Tesla Roadsters have been bricked in the US [theunderstatement.com]. Degusta's source is "a regional service manager with Tesla".
Degusta also claims if the Roadster battery completely discharges, one cannot tow the disabled vehicle by conventional means.
Re:battery vs cell (Score:5, Insightful)
That 'can not be towed' statement is really dumb. Lots of illegally parked cars have wheels that won't turn (transmission in park, parking brake on). Yet they still manage to tow them quite successfully. Jack up the car and put dollies under the wheels. What could be more 'traditional' than that? Sounds like this guys 'traditional means' involve 20ft of rope and an old pickup truck.
Re: (Score:3, Insightful)
And the original article is obviously wrong. Read the second one.
The Tesla roadster uses laptop batteries. Are laptops bricked if you leave them unplugged for a few weeks? No, of course not.
Now theoretically, if you removed the battery management system, and directly drained the cells, then chemically you would damage the cells. But that's one of the fundamental purposes of the battery management system (in your laptop battery and in the Tesla.) Power drain is cut off from the cells well before they are co
Yes. In fact, laptop batteries are bricked. (Score:5, Interesting)
I've had this happen myself with several Toshiba laptop batteries that I left in a unplugged laptop for several weeks, and a friend of mine had to pay Apple for a new battery when his Macbook-Air was unplugged for a month (while he moved).
In the case of my Toshiba batteries, I was able to open up the two battery packs and construct one working pack from the remaining good cells. The bad cells were unchargeable. (I did this because Toshiba wanted $150 for a new battery pack and I was poor at the time.)
All of these cases involved lithium battery arrays connected to a battery management system where each cell is individually monitored for temperature and charge state.
The Tesla article may be bogus, but it has a ring of truth for me because of my experiences above.
Re:battery vs cell (Score:5, Insightful)
No they don't. I've recharged and powered up laptops which have not been used for years. They still work fine. And the Tesla Roadster uses laptop batteries.
Litium-ion CELLS, if they had a resistance put across them so they completely drained would be damaged. But batteries have power management systems that that cut off supply long before they are drained. Of course cells have internal drain, but it's so low that you're talking years and probably a couple of decades before that completely drains a cell.
Tesla themselves have pointed out the story is false. The blogger got his facts wrong. A blogger being wrong - why is anyone surprised by that?
Re:MODS NOT PAYING ATTENTION (Score:5, Insightful)
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
Re:battery vs cell (Score:4, Interesting)
Teslas are also designed to avoid deep discharge: read the article! You would have to discharge it and then leave it parked for months to damage enough cells of the battery, but that would be yoru fault.
Re: (Score:3)
The allegation is that a full charge will run to flatline in 11 weeks if it's not plugged in. Less time if you drove it first.
IF true, that certainly IS Tesla's fault since the management system should have gone into a deep shutdown where nothing at all (including the management system) draws from the battery. When the charger is plugged in, THAT should power the management system and it should reboot without further intervention. In such a deep shutdown, the car should be fine for a lot longer than 3 month
Re:battery vs cell (Score:5, Funny)
I once parked my Chevy Nova at the bottom of a lake for several months, and when I pulled it back out the stupid thing wouldn't start. The weasels from Chevrolet forced me to pay for thousands of dollars in repairs just to get my car running again.
Can you believe that?
Re: (Score:2)
Re: (Score:2, Insightful)
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.
Semantics.
Statements like that one are what this piece is about. AC either hasn't read the article or is a troll. This is exactly what it explains can't happen, and statements like the one the AC made are the kind of propaganda that the misinformation campaign spreads.
Re:battery vs cell (Score:5, Informative)
No, not semantics, but rather proper use of terminology. The AC is correct - a battery [reference.com] is a collection of cells. A battery pack is a collection of batteries. (The battery being the smallest individually replaceable part in the pack.)
That's why a "D" cell battery is called a "single cell battery" - because, duh, there's only a single cell in the battery. That's why automotive type batteries [wikipedia.org] (of the type you add water to) have multiple vent caps - because each individual cell must be separately vented and/or topped off with water.
The quoted IDC analyst adds to the confusion (at least to those of us versed in standard terminology) by using the terms battery and cell interchangeably, which is the same mistake often made by the general public - you for example.
Re: (Score:3, Interesting)
> not semantics, but rather proper use of terminology
Wait, isn't that exactly what semantics is, the proper use of terminology?
"When I use a word," Humpty Dumpty said in rather a scornful tone, "it means just what I choose it to mean -- neither more nor less."
"The question is," said Alice, "whether you can make words mean so many different things."
"The question is," said Humpty Dumpty, "which is to be master - - that's all."
Re: (Score:3)
Re:battery vs cell (Score:5, Funny)
Am I really reading an argument over the semantics of the word 'semantics'?
Re: (Score:3)
Re:battery vs cell (Score:5, Insightful)
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.
There seems to be a fundamental misunderstanding of the terms 'brick' and 'won't start'. I know it's clearly far too late as I stare at a page of comments that look like "this" or 'this', but let's at least try and keep the IT geek terms out of the automotive industry, no matter how many "Intel Inside" bumper stickers you may run across.
Might I remind all of what has happened to the term "hacker" in mainstream media. I don't need or want to be labeled as a criminal for simply trying to get my damn car to start in the future, which is likely the more accurate terminology no matter what is under the hood. Mechanics probably have no idea why people keep talking about a "brick" either, for the automotive shop doesn't stock "mortar" for repairs.
Re: (Score:2)
Re:battery vs cell (Score:4, Insightful)
So a Tesla could be bricked by a failed battery but it is tolerant to a failure of individual cells.
No.. A Tesla cannot be bricked by a failed battery. It is merely a Tesla with a flat battery.. nothing more.
Terminology here is quite important, the negative word 'bricked' is being used to try and transfer a operator failure (running out of battery) into a criticism of the product itself.
Re:battery vs cell (Score:4, Insightful)
Re: (Score:2)
CellBatteryBattery Pack.
The battery pack is tolerant to a failed cell or battery.
whew (Score:5, Funny)
Good thing slashdot is here to help us debunk everything I'd never have heard about from random dipshit bloggers.
Re: (Score:3)
Yes, the real morale of the story is "Don't give a fuck what dipshit bloggers say". Going on to then debunk what they say publicly only feeds their blog views more and hence increases their ad revenue, which in turn makes it more profitable to be a random dipshit blogger talking utter shite.
Re: (Score:3)
Was the whistleblower hallucinating that?
Many bloggers are full of shit. News at 11.
You really believe that a fully discharged rechargable battery needs replacement, just because a blogger said so? You're an idiot.
Re: (Score:2, Informative)
Except this has been making the rounds, not just a dipshit blogger
http://jalopnik.com/5887265/tesla-motors-devastating-design-problem
Tow? (Score:4, Informative)
>all that needs to be done is to tow the vehicle to a charger
Another claim was that the vehicles cannot be towed.
Re:Tow? (Score:5, Interesting)
Well technically towing an electric vehicle, missing a clutch, would make it a generator, which could possibly damage the battery. However there is a youtube video showing a Nissan Leaf being towed and the battery being recharged. Don't try this at home!
Another option with the Tesla could be to lift the back wheels and tow it with the front wheels on the ground, unless there is some regenerative braking system which still acts as a generator. And yes, you want to lock the wheels if you do that.
Re:Tow? (Score:5, Funny)
Just make sure you tow it backwards...
Re: (Score:3)
I'd be extremely disappointed (but not at all surprised) to find that a car manufacturer *HASN'T* considered how to tow an electric vehicle. I suppose they just expect people to know this and book a tow truck that picks the car off the road (but then - how do you get it onto that truck without a crane?).
I'd be less surprised if your average vehicle recovery firm wouldn't know about whatever-method and tow it anyway.
I also would be 100% completely unsurprised if most electric car owners have no knowledge of
Re: (Score:3)
I don't think pulling a Tesla twenty feet from the roadside onto a flatbed truck is going to do a whole lot of damage. With that said, there are tow trucks that incorporate cranes to lift a vehicle bodily from the road; they're often used for parking enforcement. However, as you pointed out, a towing company would have to have such a truck and the wisdom to use it.
As for towing over distances with the front wheels lifted, that depends entirely on which axles the regenerative braking system operates.
Re: (Score:3, Insightful)
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 "bri
Re: (Score:3)
Re:Tow? (Score:5, Informative)
However... the Tesla vehicles already take advantage of "becoming a generator" as that is part of the "regenerative braking system" used in the vehicle. That ability to "generate electricity" not only doesn't damage the battery, but it helps to recharge the system as well and is an intended behavior... at least if you are going downhill with a tailwind.
I've seen several electric vehicles that have a gasoline-powered "pusher" trailer that provides "emergency power" for long haul trips instead of looking for an outlet for the car. It isn't even that new of an idea for that matter.
Regardless, because of the simplicity of the drive train and that the engine is not an internal combustion engine, calling a dead Roadster "a brick" is going over the top even if you can't disengage the engine from the transmission. Yes, there is a transmission in a Roadster, and there was even going to be a "clutch", but that feature was removed due to the torque issues and other problems from the supplier that was originally going to provide the transmission (something that nearly killed the Roadster when it went into production).
The Roadster is a rear wheel drive vehicle, so I don't think the front wheels are connected to anything other than the steering mechanism. In that regard, it is more like a conventional automobile too. In other words, towing the car is just like towing any other vehicle when you don't have the keys to unlock the transmission from the drive train.
Re:Tow? (Score:5, Informative)
Regenerative braking requires some pretty sophisticated power electronics, controls, and software. The Tesla's motor [teslamotors.com] is an AC induction motor [wikipedia.org]. (The AC induction motor was invented by Nikola Tesla [wikipedia.org].) An AC induction motor has copper coils for both the rotor and the stator. This is different from a DC motor (brushed or brushless) where (usually) the rotor has permanent magnets on it.
Backdriving an induction motor will result in no power generation unless the stator is energized. Even then, the associated power electronics have to commutate which phase of the stator is energized in sync with the spinning rotor. In other words, you need at least some external (i.e., battery) power in order to regenerate - this is true of all induction generators [wikipedia.org]. Without the stator being energized, you're just spinning one set of copper coils past another set (this is different from a DC motor, where the rotor has permanent magnets, which will induce current in the copper coils).
So the Tesla cannot be "jumpstarted" by towing it or rolling down a hill if the battery has discharged so deeply that it has disabled itself.
Re: (Score:2)
I've seen several electric vehicles that have a gasoline-powered "pusher" trailer that provides "emergency power" for long haul trips instead of looking for an outlet for the car. It isn't even that new of an idea for that matter.
Not pushers, just generators in a trailer, plugged into the car. A car would be nearly impossible to drive if you had something behind it, attached at a rotating pivot point, actually pushing the car. The generator is producing the electricity, not the motor in the vehicle. That's why trailers have their own brake systems -- its extremely dangerous to have the load behind a vehicle doing anything more than being pulled by the vehicle.
Re: (Score:2)
Don't all electric vehicles recharge from the wheels already? It would be such a waste of energy when breaking, since you already have most of the hardware to utilize this energy.
Re: (Score:2)
You assume that the batteries are connected directly to the wheels, but of course there is a battery management system that will prevent them from changing dangerously while being towed.
Re:Tow? (Score:5, Informative)
that depends entirely on the architecture of the motor, motor drive, and battery management circuits. The Tesla roadster, for instance, uses an AC induction motor, which has no permanent magnets in it. Unless the stator is energized and properly commutated, backdriving the wheels will not generate any power. Even in the case of a DC motor, backdriving the wheels will generate power, but if the motor drive is disabled, that power won't backfeed onto the power bus. Even then, if the battery has discharged so deeply that it has disconnected itself internally, it won't accept power unless it first communicates with a compatible charger.
Re: (Score:2)
Another option with the Tesla could be to lift the back wheels and tow it with the front wheels on the ground
This is pretty much standard procedure for towing AWD vehicles as well so it's not like the capability/knowledge doesnt widely exist. This whole thing is FUD.
Re: (Score:3)
Re: (Score:3)
Every tow truck I've called over the last 15 years were a flat bed type. One of my cars ejected a wheel while driving. The tow truck had no problem dragging the car 15ft onto the flatbed and returning it to the dealer.
Unless Teslas have some magical tires the permanently grip the road when their batteries die I don't see any reason why any tow truck company could not easily tow it.
Dragging a car 15 ft up a ramp isn't going to regenerate anything significant.
Re:Tow? (Score:5, Insightful)
http://www.autoobserver.com/2011/02/towing-raises-new-issues-when-evs-are-involved.html [autoobserver.com]
Re:Tow? (Score:4, Informative)
Another claim was that the vehicles cannot be towed.
Maybe by a rope and your backwoods service jockey.
Winch it onto a flatbed, even locked wheels skid. Can't get to an end of it because it's parallel parked? There are these funny little things that scoop each wheel and then you basically push it sideways to wherever you CAN lift it. If you are towing something with AWD without a flatbed handy? Lift one end like anything else and use the wheel-scoop style things to jack the other end off the ground and tow it on them.
There are ways, and a good tow service knows them.
Re: (Score:2)
Recovery vehicles that take the car completely off the road are not rare. And cost rather less than $40,000 to hire.
This IS a LiIon failure mode though (Score:5, Interesting)
Re: (Score:2)
OK. so my question is then: what does "bricked" mean, technically, in the Tesla battery case? If a protection circuit has kicked in and isolated the battery, then that should save the battery itself from permanent damage. The story is that Tesla is charging $40,000 for replacement of the complete battery pack, which suggests that a protection circuit has NOT saved the battery from permanent damage. Either that or the battery can be fixed and resold, and they're ripping off the customer. Those are the only p
Re: (Score:3, Insightful)
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.
Re:This IS a LiIon failure mode though (Score:5, Interesting)
Or he's NOT and you are just assuming he is because you either dislike the blog/blogger or are utterly ignorant of the facts. The communication emails are public knowledge, and the 40 grand cost is NOT "made up from whole cloth" and has been confirmed by Tesla.
Geez, people, RTFA for crying out loud.
Jalopnik article on the issue:
http://jalopnik.com/5887265/tesla-motors-devastating-design-problem [jalopnik.com]
Jalopnik article about the attempt to smear the whistleblower:
http://jalopnik.com/5887499/who-is-trying-to-smear-the-tesla-battery-problem-whistleblower [jalopnik.com]
Gallery of screenshots of emails:
http://jalopnik.com/5887504/tesla-emails-gallery/gallery/1 [jalopnik.com]
Read read read. Then rethink and reassess.
Re: (Score:2)
I thought the same thing, and was thus expecting that the first response from Tesla would have been "$40,000 is a completely ridiculous, inflated number with no basis in reality." But that's not their response. It's not even, "Yeah, earlier versions of our technology could have had this issue, but we've totally fixed it for the upcoming Model S and Model X versions". But no, the response we're getting from Tesla is more along the lines of "well, yeah, you need to keep it plugged in."
Which frankly makes m
Re: (Score:2)
Those are the only possible explanations for a $40,000 bill, and neither look good.
The other explanation is that the blogger is full of shit. Apply Occam's Razor how you will...
Weak! (Score:2, Interesting)
"The battery management system of the Tesla Roadster keeps the battery from being discharged to a damagingly low state of charge under normal driving conditions."
One of the original points was that if the car was left alone for a relatively short period of time then it would discharge fully due to physics, nothing the power management system can do about it.
This is a pathetically weak rebuttal to be honest. Take each one of his points and give us a counter-point to each one. So far it seems to be "He doesn'
Summary is right, BMS is probably the cause (Score:4, Interesting)
When I read the blog article I thought exactly the same thing. Cells left to self-discharge will not go below their thermodynamic equilibrium, which is more or less the potential at which they are built (remember, Li-ion batteries when assembled are discharged by nature). There is no danger of damaging the cells when self-discharge occurs.
Another issue is when the cells are actively overdischarged, however a Li-ion battery is more likely to explode due to overcharge (plating of Li metal at the negative electrode) than overcharge (insertion of too much lithium in the cathode and electrolyte depletion).
Most likely the BMS is refusing to come back to life unless hooked up to a secret Tesla computer, but I guess the packs can be refurbished.
Also, kudos to the idiot recharging the car with a 30m cable extension (that's what 100 feet is, right?).
Re: (Score:2)
It's the same cable that my house is wired up with and I have certificates showing its safety (needed some re-wiring in my kitchen, UK law states whole house needs checking).
Re: (Score:2)
Since when... (Score:2)
Caught red-handed! (Score:5, Funny)
AHA!!!! SEE? They admit it!!!
Re: (Score:2)
Admit what? That they have a real battery pack in their vehicles? I had no idea that anybody doubted that the Roadster was an electric vehicle.
Re: (Score:3)
Admit that you wouldn't get the joke even if it was a BRICK HITTING YOU IN THE FACE.
Which Battery? (Score:5, Informative)
When you hear Lithium Ion Battery, you need to understand there are many different types of cell.
A battery consists of an Anode, Cathode and Electrolyte.
In LiIon based batteries, the electrolyte is a Lithium Salt, and the Anode is generally Carbon.
In LiPolymer batteries the electrolyte is held in a polymer of Lithium Cobalt or Lithium Maganese (this is the most common format of battery in consumer electronics)
In a recent project a for a hand held RF device, we chose LiFePO4. Mainly because it is so robust. Although it does not have the same capacity as LiPoly, you can grossly overcharge it and even drive a nail through it and it wont catch on fire. It also has much longer life over LiPoly.
LiPoly are very sensitive to overcharge, overdischarge, and mechanical damage, thus have a circuit to disconnect the battery when over discharged, thus the 'bricking' effect.
Tesla orginally used 18650 LiIon batteries with I believe had a LiCoO2 cathode, although I now think they are changing to pupose built cells. They would have a more sophisticated battery management that would prevent 'bricking'...... well at least one would hope...
Re: (Score:3)
No, a cell consists of those things - a battery [wikipedia.org] is a collection of one or more cells. The public often confuses the two because the batteries most often encountered in day-to-day life are in fact (technically speaking) single cell batteries.
Depends on cell configuration and BMS (Score:2)
If Tesla is using 8000 cells, it is probably putting something like 6-12 cells in parallel packs, and then wiring up each of these packs of cells in series. The parallel cell packs provide the current capacity while the packs in series provide the high voltage required to operate the motors.
If an individual cell in a pack goes bad by having a degraded capacity, th
The term "brick" is overused these days (Score:3)
Folks who don't understand what the term originally meant, now use it to describe any tech problem as bricked. As in:
"My browser says 'page not found' . . . my system must be bricked! I read that 'bricked' means 'not working' in the IT business . . . right?"
Re: (Score:2)
Jalopnik disagrees with Jaffe (Score:4, Informative)
You might want to do your research. (Score:2)
Uh... you can easily burn out a lithium ion battery like the ones tesla uses by going below 1% charge. If their system isn't intelligent enough to completely stop battery use at 3%, and report that as 0, it's entirely possible to kill the whole power plant.
News or Press Release? (Score:3)
Slashdot is losing it (whatever it is). This article is pure Tesla Co. press release.
Oh boy. (Score:5, Informative)
Just what we need--more "analysts" fighting bad bloggers' bad information with more bad information.
Let's start with the "more than 8000 individual batteries". These are 18650 cells (a standard form factor, a bit larger than an AA cell), and a Roaster has only 6831 of them. They are not "individually managed". Rather, they are grouped into a 69-parallel module, with 99 modules in series. (69x99==6831)
It is asinine and a distraction that Tesla (and everyone else) constantly obsesses about the 6831 cells. For all practical purposes it is a 99-cell Li battery, but rather than using monolithic cell modules, Tesla (like ACP before them) builds modules from smaller component cells, because they yield better cost ($/Wh) and specific energy (Wh/kg), with more-favorable cooling and safety characteristics.
Other than a built-in per-cell PTC device (which Tesla is likely no longer using), any "management" is done at the module level, and the battery is treated as a 99-cell series pack. The PTC is a passive cell protection device, designed to save a cell from a failed-short condition, but they also cause as many problems as they prevent.
Secondly, the "solution" is not nearly as simple as "shutting the pack down" when it reaches "an extremely low depth of discharge".
The Li cells themselves do not discharge themselves quickly when idle--perhaps 5 or 10 percent per year. However, small parasitic (e.g. maintenance) loads will slowly deplete the cells' energy. Herein lies the "grain of truth" that is probably at the center of this greatly dramatized "journalism".
Li traction batteries typically have on the order of 100 cells (or more for 600V systems), and each cell must be monitored to keep its voltage and temperature within a safe range. Typically the monitors are powered from the cell modules directly, and the competing design constraints are many: Small packaging, low cost, low power, electrical isolation, and so on. It is possible, but not trivial (nor cheap) to make a cell monitor draw zero current when its host module is at low voltage.
The original rant (er, blog) claimed that the parasitics would deplete a battery in 11 weeks, which is bordering on implausible, and if true, it would represent a staggeringly high rate of self discharge. Per Chelsea Sexton (who knows what she's talking about), there has not been "a single 'brick' story that didn't involve some extraordinary circumstances".
Lastly is the notion that the traction pack is necessarily destroyed by a deep discharge event. While it is true that deep discharge (and particularly cell reversal) will cause some permanent damage, the damage is in the form of higher impedance, and this is far from rendering the module useless. The battery can be brought back via trickle charging and a per-module impedance test will reveal if any are too far gone.
Made by monkeys (Score:3)
A proper battery management system will shut down absolutely everything (including itself) when the battery is approaching full discharge. In that state, there's no reason the battery pack shouldn't be able to go for a year or two without reaching the point of failure.
Likewise, a proper system would allow the management system to power back on (reboot) when the car is plugged in, and then begin recharging the battery.
The cheapo protected 14500 (AA sized) LiIons I use here have that feature. The disconnected discharge rate is a few micro-amps. If I run it "flat", I can stick it in a charger days or weeks later and charge it back up. Apparently, the Tesla never actually shuts down standby systems and as a result the battery can be irreparably damaged by sitting for 11 weeks (if starting from a full charge) or much less (if the car was driven before sitting).
Other electric and hybrid vehicles do the right thing and go into total shutdown when the battery gets too low. Then you wake it up by plugging it in.
This isn't a general problem with electric and hybrid vehicles, this is a glaring design flaw in the Tesla.
Re: (Score:3)
Electrolyte of Li-ion battery completely freezes somewhere around -30C. Degradation of performance (i.e. increase in resistance of the electrolyte and subsequent decrease of available power) starts sooner, but there are additives for that.
I guess there are few places on earth where a roadster is left parked for an extensive period of time in order for the whole pack to freeze.
Re: (Score:2)
Re: (Score:2)
Some cars already come with battery heating systems which prevent the problem, unless you park for an extended length of time in -30C without connecting power.
It seems that people living in areas where -30C is common are rather good at dealing with the challenges of gasoline/diesel engines at those temperatures. I am sure that they will find creative solutions for getting electric vehicles running too.
And if no solution is found in the next 10 years, that is probably ok too. If we switch everyone else to el
Re: (Score:2)
It seems that people living in areas where -30C is common are rather good at dealing with the challenges of gasoline/diesel engines at those temperatures.
Some places, especially in the northern soviet states, have had what look like 'charging points' along the street for decades. Your car has a simple heater circuit in the cooling fluid (and sometimes ones on the fuel system and in the cabin too) to stop any terminal freezing of the coolant etc.. and give it a better chance of starting. Everybody plugs in on a winter night.
Re: (Score:2)
Defined as someone who wishes they could be a journalist, but doesn't want to actually have to conform to any kind of standards
Sir, could you please point me the direction to those journalism standards you talk about?
Seriously, very few journalists follow standards; not the good ones at least (e.g., priority to reporting facts over writing a nice story, etc). For instance, eventually I come across articles in the newspapers reporting some stories which I have witnessed myself. Every single one of them until today have had factual errors, and some of them quite gross.
Re: (Score:3)
For instance, eventually I come across articles in the newspapers reporting some stories which I have witnessed myself. Every single one of them until today have had factual errors, and some of them quite gross.
I've been in the know on a couple situations (both personally and professionally) that were reported in the press, so I wanted to echo what you said. The media gets it wrong. A lot. It makes you wonder how many articles are factually incorrect for topics you aren't intimately familiar with.
Re: (Score:3, Informative)
The original post said bricked because that is exactly what the author meant. If you read it you will see this. He says if a car is left sitting long enough it will fully discharge and the car will be inoperable until the owner buys a new $40,000 battery pack from Tesla.
Re: (Score:3)
If you can repair an item just by changing its battery, it's not bricked.
Re:"Battery" (Score:5, Interesting)
the IDC analyst isn't "just a blogger", it's a guy who's trying to write a rebuttal to sound cool, but too bad he didn't actually go and try to look for the actual cases - instead he's just going "can't happen because of pr materials a, b and c". if he starts with that a battery of batteries can't have anything wrong with it by design.. comes off almost as a fanboi who didn't even read the news piece about the blog posting(which states that you can't even tow them, which sounds a bit strange but not _that_ strange if it won't fire up any elecs. of course you could tow them still lifting it on a truck or whatever)
Re: (Score:2, Informative)
http://www.wired.com/autopia/2012/02/bricked-tesla-roadsters/
Wired contacted one of the owners, it can't have been too hard.
Re:"Battery" (Score:4, Informative)
Umm.. "Bricked" is a term for any phone that gets ... well.. "Bricked" as we call it..
It's been around since pre-iPhone.. phone modders have been unhappily bricking their phones for quiet a while to push it to its limits :-) iPhones, as usual, just made it "Popular"... the did not invent it.
Re: (Score:2)
Amazing how the Apple haters manage to bring up the iPhone in every topic. Must be some OCD thing.
We were using the terms "bricked" and "brick" at Symbian back in 1999. And I'm sure it wasn't a new term them. That was a long time before Apple.
Re:"Battery" (Score:4, Informative)
Re: (Score:2)
Re: (Score:2)
The term became "cool" when people figured out ways of bricking iPhones. It was then rapidly expanded to include any kind of malfunction of an iPhone (all in the name of bashing Apple and getting more visitors to whatever blog published the article). These days "bricking" something seems to just be another way of saying "cause any kind of malfunction or failure which temporarily or permanently leaves the device unusable".
(And for the usual Apple haters: Nowhere in the above paragraph did I say iPhones or Ap
Re: (Score:3)
I never heard of rounded corners until the iPad.
cheers,
Re: (Score:3)
"Bricked" is a term we used long before the iPhone for equipment finally failing to respond to any attempt to get it running again without any evidence of a physical damage. :)
I've seen many a bricked switch or router in my life which failed during an update attempt
Re: (Score:2)
Bricking didn't originate with iPhone jailbreaking and has been around for considerably longer. I can remember encountering the term for the first time while tinkering with a Linksys WRT-54g back in 2003 and it was already old by then.
Just because the iPhone can be bricked doesn't mean Apple invented the brick!
Re: (Score:2)
He SAID we all forgot about it. Sheesh.
Re:To brick or not to brick? (Score:5, Interesting)
The first article says, "This is a problem and Tesla should do something about it." The second article spends three paragraphs explaining that the original article gave a simplified explanation of how the Tesla works and is wrong about the possibility it discusses and how something the original article never said can't happen. Then it spends a paragraph explaining how the problem the original article actually talks about can indeed happen and how that is the nature of rechargeable batteries and there is nothing Tesla can do about it. Finally it spends another paragraph talking about how the original article is one of many that is spreading misinformation about electric vehicles.
Re:is this a paid summary or what??? (Score:5, Insightful)
Yes, the claim seems to be actually true: http://jalopnik.com/5887265/tesla-motors-devastating-design-problem [jalopnik.com]
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"?
Re:is this a paid summary or what??? (Score:5, Interesting)
If you can afford a Tesla, you can afford to RTFM and get a trickle charger.
Probably (although I am sure that many people who have enough money to buy one won't read/understand all the technical stuff and will want the car to "just work") - but that still leaves us with the point that the battery pack can go kaputt within a couple days if the car is not charged (if the car was already at low charge) - which is something which needs to be communicated to customers far more clearly than just a sentence here and there that it is not good to let the battery go completely flat. Because I am sure that for almost every person who is not very familiar with battery technology, the EXPECTED consequence of a flat battery would be "recharge it again and you're good to go". If there is the possibility of making a $40k mistake, I'd expect the car to go full "star trek red alert" on me when I park it somewhere at less than 10% charge, and to start sending "help! I am dying!" SMS when the battery goes below 5%.