Do you know that you must keep your battery charged?

[markwj]

Other posts in this thread suggested that the vehicle activates some emergency procedure when running dangerously low on SOC (like SMS alert). They ignore that constant supervision of SOC and active measures when reaching alert condition consume additional energy.

In my discussions with Tesla regarding OVMS, one of the concerns they raised was power drain. The actual drain depends on a lot of factors - and in particular the cellular signal level. The figures I gave them (obtained by direct measurement of a running OVMS module in various configurations):
Idle: 40mA @12V
Cellular Network Registration: 100mA @12V
Network activity: 80mA @12V

The vast majority of this is the cellular modem (the PIC we use has minimal power consumption). Worst case we see seems to be 100mA @12volts, or about 1.2watts.

Based on a full 53KWh main battery, that would power the OVMS module (worst case) for about 44,166 hours (>5 years).

My test bench runs off an 8-pack of 1.2volt 1.9Ah batteries (~ 9.6volts 1.9Ah, or 18.24Wh). Theoretically, worst case, that would drain to zero in about 15hours. I get at least that in normal development use.

Anyway, bottom line the OVMS module draws between 40mA and 100mA @12V. Not sure about the Tattler. I guess the CPU will draw more, and the GSM modem less, compared to OVMS.

Has anyone done the calculations for a 5% SOC loss in a week? I really can't believe the VMS is anywhere near that - it must be fans and pumps.

The coolant pump on v2.5 cars turns off after the car is idle (off) for 5 minutes. It seems to wake up once every 24 hours. Is that now the same for the earlier v1.5 cars, or is somewhere in between that and 24 hours-a-day?
That Little Water Pump
The original v1.5 problem was reportedly 24.5kWh a week (46% of SOC @53kWh).

[smorgasbord]

I thought this was a worthwhile, if quick, read.

The actual battery problem was tiny... calling a customer fears irrational and smearing the whistleblower is something that just is not done unless Tesla wants to establish a reputation for poor customer service. Using media to intimidate, threaten and smear a customer for making a public customer complaint is something that just blows away billions of dollars of customer goodwill. If Tesla follows the same modus operandi that it has followed in the past with Top Gear -- it will try to threaten and intimidate first, then it will fill a libel case, get rejected, file a 2nd libel case, get rejected again and then plot its next move as it keeps attacking the messengers.

Tesla ...could have had a free PR goldmine -- it could have showed Toyota and all the other automotive OEMs how complaints could be handled even better; for a few thousand dollars, this could have been a crowd-sourced EV teach-in and Tesla lovefest. The "teachable moments" in life like this cannot be wasted.

While I don't agree with all of the article, I do agree that Tesla did not handle this well. Many here have argued that Tesla is in the right. But, Tesla needs to look beyond that, they need to keep in mind the Big Picture. Tesla should always keep in mind that they're trying to lead the wave towards mass market adoption of EVs. That means calming people down with the batteries. The batteries, after all, are really the only thing stopping EVs from taking off: they have limited range and/or high cost. For many people, that a car left alone will destroy its battery over time is simply unacceptable. And, it sounds like Tesla is fixing this for Model S anyway, so it just makes Tesla look immature to not fix this early adopter's car.

The end result here is that Tesla is paying too large a price for their rightous attitude.

[stopcrazypp]

I thought this was a worthwhile, if quick, read.

While I don't agree with all of the article, I do agree that Tesla did not handle this well. Many here have argued that Tesla is in the right. But, Tesla needs to look beyond that, they need to keep in mind the Big Picture. Tesla should always keep in mind that they're trying to lead the wave towards mass market adoption of EVs. That means calming people down with the batteries. The batteries, after all, are really the only thing stopping EVs from taking off: they have limited range and/or high cost. For many people, that a car left alone will destroy its battery over time is simply unacceptable. And, it sounds like Tesla is fixing this for Model S anyway, so it just makes Tesla look immature to not fix this early adopter's car.

The end result here is that Tesla is paying too large a price for their rightous attitude.

I think the TTAC put it best. If Tesla had known Drucker was going to go to the media in this manner, the best way to deal with the issue would have been to ask him to sign an NDA that makes it clear Tesla doesn't have any legal responsibility for the damage and then provide him with a free replacement battery in good faith.

But after the media coverage, it would be more like admitting fault, and setting a precedence of replacing for free batteries damaged from being overdischarged (something no manufacturer would do, including Nissan with the Leaf). If the same thing happened again (and the Model S is certainly not immune to this, it just takes longer to reach this point), the customer can easily point to this precedence and Tesla would be hard pressed not to replace the battery without another round of bad PR.

After this media coverage, I think standing firm and doing more to inform people of the need to keep the car plugged in and the consequences of not doing so for long periods of time, will do more to prevent this issue from happening to someone else, while also limit liability to Tesla.

[JRP3]

I'm not sure which way to think on this one actually, the good PR if Tesla had helped out vs the potential for future claims against them. The one case that really concerns me is the person who actually did as instructed and plugged the car in, albeit using too long and too small a cord to support the pack. A lay person could reasonably not be expected to know the current requirements of the vehicle and the capacity of that cord, unless Tesla also clearly spelled out both in writing. Maybe Tesla could have split the cost of a new pack in a good will gesture, acknowledging that the early vehicles really drew too much power at rest. Especially since they made changes with later models to reduce idle current draw.

[dmckinstry]

And then some guy would park it in his garage for 2 months.

Is there enough power to run into a battery pack? I understood that they can't even keep the battery topped up. 100 amp 12 volt to run a vent fan. On a bright and sunny day.

That's 1.2 kW. Most portable electric space heaters (with blowers) don't draw that much. That 100 A must be a typo.

[dsm363]

I think this guy painted Tesla into a corner as said above by having his friend go public with that 'blog' post.

[roblab]

That's 1.2 kW. Most portable electric space heaters (with blowers) don't draw that much. That 100 A must be a typo.

I hate it when that happens. But I'm used to being wrong. It's 12 volt 100 watts.

[richkae]

I disagree with Tesla eating the cost of giving this guy a new battery.
The money has to come from somewhere.
Do you want every Roadster owner to mail this guy $20 to pay for his new battery?

If Tesla stopped producing new cars after the Roadster and their only business was maintaining Roadsters, they would have to pass the costs on to the Roadster owners or reduce service to the tune of $20 each.
Since they plan to have more customers, they can pass the cost on to all of them at a much smaller amount.

But either way - no thank you.

[Norbert]

I thought this was a worthwhile, if quick, read

No, I think this article substantially misses the point of what happened. It says Tesla should have investigated the root cause. But as the letter to the customer with the timeline (of what happened) shows, Tesla investigated the logs and came to the conclusion that the Roadster behaved according to spec. What has happened was exactly what the manual warns about, and within those timelines. The root cause was indeed known, both in this case and in general, and is communicated by the user manual. After reaching SOC 0% after a few weeks, the battery was still holding a voltage for 14 days, if not more (at that point the car stopped logging, until that point it was still able to).

Neither the Leaf nor the Model S completely solve this problem, AFAIK. Nissan said you need to recharge the Leaf 14 days after reaching SOC 0%. The Roadster endured as much, even though Tesla says you need to recharge immediately. The Model S merely improves the timeline of the battery events to the point where it is (even) easier to manage. You still need to know that the battery will discharge over time, and you still need to respond to the warnings.

Something that received little attention here is that some of the discharge is due to the Roadster keeping the battery temperature at a level which is optimal for the lifetime of the battery. In this sense it is not a design error, even though Panasonic+Tesla were able to improve this design for the Model S and the battery chemistry it uses. It is merely that Tesla expects the customer to plug it in (soon enough).

[smorgasbord]

Tesla investigated the logs and came to the conclusion that the Roadster behaved according to spec.

In layman's terms, the spec says just parking your car for a couple of months can destroy your $40K battery. So, now instead of Range Anxiety, we have Storage Anxiety. That is a design error.

In my view, there should be a manufacturer's recall on this. After a few weeks of sitting unplugged and with SOC below a certain level, the battery management system should switch from active management (preserving long term battery life) to passive management that will prevent catastrophic battery failure. Better a battery that gives a few less miles than a battery that gives zero miles. That Tesla improved this for Roadster 2.0 is good. That Tesla improved it even more for Model S is good. So, why can't this be retrofitted to previous models?

Again, the real point here is how Tesla reacted. The author's analogy about suing Top Gear was absolutely right. Yeah, the Top Gear episode was misleading. Taking them to court was not the solution - that strategy backfired when the court ruled against them. The proper solution there was a marketing campaign with cross-country Roadster events, etc. Tesla's long term view solution here should have been to fix this guy's car (and the other bricked cars) for the price of the extended battery warranty plus some years, and most importantly issue a recall to prevent this from happening to any other Tesla vehicle.