Comment by Nelson69 | Hacker News Reader

Comment by Nelson69 | Hacker News Reader

Parent Full thread

Many of the things that "brick" an ICE can be repaired at relatively low costs. And almost all of those things brick the car by using it, Teslas will brick when you don't use them, you lock it safely in the temperature controlled garage and go away for too long and it dies.

It strikes me as a design problem of sorts, you've got a relatively expensive and sophisticated sports car with piles of electronics. I would think that maybe they could detect a certain critical level of energy is left in the batteries and flip a toggle that just shuts them off which wouldn't last forever but could buy you some more time maybe.

My grandfather's Buick has GM's onstar stuff in it, couldn't your roadster send a text message or something? Maybe they could have some sort of emergency mechanism to just plug a normal car battery in to gain a little charge from.

I like what Tesla is trying to do, they're changing the conversation and ultimately when I look at the auto industry I think more startups are needed. They're a startup though, the Top Gear story, I don't think it was bad or inaccurate, the Tesla just doesn't look like it's in the same league as many of the other sports cars they drive around and then this battery thing, rare as it might be they need a good story for it. How many drivers have run out of gas when they are experienced and know better? Stuff happens, it's more common than you might think, with an ICE it's just embarrassing and inconvenient, with a Tesla it might set you back some serious money.

From the article: "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. It's true that a full discharge to zero percent state of charge can potentially be damaging to a battery. However the battery management system of the Roadster won't allow the car to reach that low level of charge."

"However the battery management system of the Roadster won't allow the car to reach that low level of charge."

I realize that you are quoting the article, but the owner's manual is simply not in agreement with this sentence.

From the Roadster 2/Roadster Sport owner's manual (italic emphasis is mine):

"Important! Caution: If the battery’s charge level falls to 0%, it must be plugged in immediately. Failure to do so can permanently damage the battery and this damage is not covered by the New Vehicle Limited Warranty. Also, if you allow the battery to fall to a critically low level it may not be possible to charge the vehicle. If you are unable to charge the vehicle, contact Tesla Motors."

[...]

"However, situations may arise in which you must leave the vehicle unplugged for an extended time (for example, at an airport when traveling for a couple of weeks). If this is the case, it is your responsibility to ensure that the battery does not become fully depleted."

[...]

"If for some reason, you are unable to keep the vehicle plugged in when it is not being used, it is up to you to preserve battery life by paying attention to the charge level and the temperature [...]"

There's a lot of conflation going on here.

The original article seemed to be stating or implying that the car's own on-board systems would continue to draw power well past the danger point, drastically reducing the time to destroy the battery.

This article seems to be stating that the car's systems will stop drawing power. The battery will continue to discharge in this situation, due to natural processes, but discharging to a point that destroys the battery takes much longer in that case.

This means there is still a risk that, if left unattended for extended periods (on the order of at least weeks, perhaps longer), the battery will become unusable. But this is not the same as the original claims which seemed to be arguing for design flaws which would hasten that process.

I don't think you are noticing how, if you read the wording closely, this is NOT a rebuttal of the bricking claims. The rebuttal talks about "normal driving conditions". This is non-responsive to the claim in question, which is that if you drive the Tesla for a while til the battery is somewhat low, and then don't plug the car in to charge properly, it can become completely disabled in as little as a week.

So in other words, the original blogger was not claiming that "normal driving" will brick the Tesla. So talking about how the battery management system won't let it brick itself while you are driving it is a misdirection tactic. It does not rebut the claim.

"However the battery management system of the Roadster won't allow the car to reach that low level of charge."

In that case, Homer Simpson would never want one in his house. Also, why are they in the car business? I what their battery management system. It, apparently, can make energy out of thin air, to counteract the losses in the batteries.

The "article" confirms that Teslas can be bricked in exactly the way reported:

There is a fundamental problem when any rechargeable battery is discharged and then left to sit for months. Any boat owner understands that that's why you plug in a trickle charger when the craft is put into storage. The same should be done for any electric vehicle. However, to imply that the Tesla Roadster has a fundamental design flaw because of the nature of electrochemistry....

The rest is the lovely art of spin. It reads like a rebuttal of the bricking claims and vindication for Tesla, doesn't it? In every superficial aspect, that's what it is, but the substance doesn't match the form and tone. Welcome to PR.

> How many drivers have run out of gas when they are experienced and know better?

Not many, right? I've certainly never even come close to running out of gas, and I can only think of one time in my life where anyone I knew ran out of gas (and that was only yards away from the gas station).

Maybe it's a function of where you live. I think I have witnessed it more often than that, relatively rare but with a $40k penalty just having it happen once is pretty extreme. Maybe running out of gas was the wrong analogy.

I still think you could design some better fail safes in and then if it is as rare as they say, why not cover it in the warranty?

Pretty much everyone i know has a 'ran out of petrol' or at least a 'woh nearly ran out of petrol had to keep her at 55 all the way and rolled her in' story.

Reply on news.ycombinator.com