Do you know that you must keep your battery charged?

[NigelM]

Unless it was in storage mode.

Quotes from Tesla, comments from me:

When plugging in a nearly empty car that is set to Storage mode, the charge will generally stop at around 20%. The car will then settle into its normal Storage mode rhythm, topping up and discharging between 10% and 50% as the car sees fit.

Anyone leaving for a couple of months should charge their battery before putting it in storage mode. In any case unless the storm starts the first day (under which circumstances you'd check your fuses, no?) the battery makes it to a higher SOC and then:

Part of the benefit of Storage mode is that there is less work required from the HVAC system to keep the battery happy and safe, and therefore, less energy is consumed while stored.

The point being, your average SOC when the power goes out may even be higher than if you had left it unplugged to begin with.

 

[markwj]

Unless it was in storage mode.

Storage mode maintains ~50% SOC. even at 5%/week, that is 10 weeks plus whatever sub-zero margin there was left. Looking at the disclosed logs for the one 1.5 car, that was 3.5%/week plus 2 weeks before shutdown = 16 weeks by my reckoning.

 

[Doug_G]

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.

I don't buy it. I once plugged my car into an extension cord provided by a hotel and it immediately popped up a charging error, "Extension Cord Detected". Evidently too much voltage drop. I asked the hotel if they had a heavier gauge cable; they did and the car charged normally.

 

[3lectronica]

All the roadster owners should do a YouTube community response to this BS. Show folks what it's really like to live with the car, and how easy it is to just plug it in (as if it were inconvenient to do so)!

 

[doug]

Wow that blogger guy heavily references this thread.

And he still fails to mention his connection to Drucker.

He digs up a video from early 2008, before the car reached anyone's hands (besides Elon). Was there even a manual yet back then?

He even takes what Elon said out of context. Elon was talking about the batteries not having a memory effect, not long term storage.

 

[Norbert]

And he still fails to mention his connection to Drucker.

He digs up a video from early 2008, before the car reached anyone's hands (besides Elon). Was there even a manual yet back then?

His reference to the 3-minute mark of the Jay-Leno-video is really nonsense. Elon is probably a bit excited as he says: "You can actually plug it in anywhere, you just need an extension cord." So with "extension cord", Elon is referring to the 110V charging cable (not to an extra extension).

(EDIT: otherwise he would have said: 'you might need'.)

 

[dpeilow]

I don't buy it either. I've charged on extension cords. If they are heavy duty it works fine, no different to the outlet in your garage being on a long spur. If they are too lightweight it throws an error immediately.

 

[eledille]

It's a simple reality that given enough time unattended any battery will eventually discharge to zero and be ruined. (Except for maybe Edison nickel batteries).

Nitpicking, and not relevant to modern EVs, but nickel-cadmium cells can be safely discharged to zero and stored shorted. My NiCd-powered EV has a design flaw that causes it to become inoperable when completely empty, but the battery is not harmed by it. It just has to be removed from the vehicle to charge again because the main contactor will not operate without traction battery voltage and the battery cable is inacessible without removing the pack.

I believe the liquid sodium Zebra battery in the newest generation of Think City also tolerates storage in discharged state, but it needs a couple of days to thaw the frozen sodium before it can be recharged. This technology might still be relevant, it's energy dense and very reliable.

 

[eledille]

Maybe this is one of those cases where an EV isn't the right car for everyone at this time.

Tesla has stated that the Model S will be fine for at least a whole whopping year. They have also stated that it does exactly what several people have suggested in this thread - kill all parasitic loads and hibernate when voltage reaches a certain lower threshold.

So it seems to me that Tesla has completely fixed this problem and that bricking is now an extremely unlikely scenario. Anyone who insists that he is unable to ensure that the car is plugged in and has power at least once a year doesn't need a car, he needs a tent, a knife (preferably made of flint so it doesn't rust), a good bow and a few arrows.

If this is purely a software fix then I think Tesla should upgrade Roadsters during service. If there are hardware changes, then Roadster owners will probably just have to get someone to check the car from time to time when they take a three month trip.

 

[AndrewBissell]

Tesla has stated that the Model S will be fine for at least a whole whopping year. They have also stated that it does exactly what several people have suggested in this thread - kill all parasitic loads and hibernate when voltage reaches a certain lower threshold.

So it seems to me that Tesla has completely fixed this problem and that bricking is now an extremely unlikely scenario. Anyone who insists that he is unable to ensure that the car is plugged in and has power at least once a year doesn't need a car, he needs a tent, a knife (preferably made of flintstone so it doesn't rust), a good bow and a few arrows.

If this is purely a software fix then I think Tesla should upgrade Roadsters during service. If there are hardware changes, then Roadster owners will probably just have to get someone to check the car from time to time when they take a three month trip.

This.

 

[JRP3]

I believe the liquid sodium Zebra battery in the newest generation of Think City also tolerates storage in discharged state, but it needs a couple of days to thaw the frozen sodium before it can be recharged. This technology might still be relevant, it's energy dense and very reliable.

The Zebra battery has it's own problems, poor efficiency from high power usage to keep it in a molten state, and worse energy density than most lithium last I knew.

 

[eledille]

The Zebra battery has it's own problems, poor efficiency from high power usage to keep it in a molten state, and worse energy density than most lithium last I knew.

The Zebra is very different from lithium-ion, but may make a lot of sense in certain applications. It's currently not power dense, but that's not surprising given the amount of research that has gone into it it vs. lithium ion. I think it might be improved a lot. It is relatively energy dense, though. The Think City Zebra pack is approximately as energy dense as the Roadster's complete battery pack at 28.3 kWh/250 kg = 113 Wh/kg versus 53 kWh/450 kg = 118 Wh/kg. Efficiency is very poor if the car spends a lot of time standing still, but losses during use becomes heat which is contained inside the pack, so the battery does not need to expend extra power to stay hot if it is used often. It degrades much more slowly with time and cycles than the Roadster battery. I agree that lithium-ion is more promising, however.

What I'm trying to say is just that different battery chemistries behave differently. Some don't mind being stored at 0 volts while this instantly destroys others. Some have low self discharge, others high. Some need to be hot, others like to be cool, and so on. They are simply different. Even different versions of a single chemistry can behave very differently, Altairnano being one example.

As an EV owner you really want to keep your particular variant happy, so reading the manual is a must

 

[smorgasbord]

He even takes what Elon said out of context. Elon was talking about the batteries not having a memory effect, not long term storage.

Yes, he took advantage of the unfortunate use of the word "leave" by Elon, and neither person actually mentioned the phrase "memory effect," although it's clear from Jay's comments that's what he was talking about.

 

[vfx]

...
Also, he states "It’s not clear when Tesla began having new Roadster buyers sign this form". Does anyone know?

Going forward, does it even matter?

 

[vfx]

Even as an EV owner I really see this as a problem. Lets say....

Ignoring that the Model S addresses this problem.

This sounds like one of those, What If I want to drive to my great gramma's house?" questions. The answers are as easy as "rent a car" or Have someone check on your car.

I mean, if an EV owner is in a horrible accident and is in a coma for a year maybe they have a dead EV in the garage. Meanwhile they might have lost the house, wife and job. Stuff happens. Electric cars are not perfect, just more perfect than gasoline cars.

 

[daniel]

Even as an EV owner I really see this as a problem. Lets say you are away at a summer home, two month mission trip, long vacation and there is a storm and the breaker trips on the car. Imagine coming home to find you have to spend more for a repair than most cars cost?

Then, when the car gets to 5% SoC you get a call (or an email?) from Tesla. You phone (or email) a neighbor or friend and ask them to check on it. I always leave a spare key with a trusted neighbor.

Another possibility is last year I had a bad bicycle accident and if it were not for my helmet I would not be writing. A few months in the hospital suddenly became a possibility. Since my wife has no desire to drive the Tesla would she verify it was plugged in?

If you are in a coma for two months, you have much more serious problems than the car. But if there is someone who checks your messages (your wife?) they'd get the message and be able to deal with it. If you are hospitalized but conscious, you get the message one way or another.

The trade-off is that Tesla uses a battery type with greater energy density by both weight and price, but the "cost" is that it requires more care, and therefore more power, than other battery types (some of which weren't even available when the Roadster was designed). With LiFePO4 the Roadster pack would have needed less care, and could have been designed to endure years (?) without being plugged in. But the car would have cost more and had less range. Trade-offs.

The relatively shorter safe no-plug time is the "price" of getting the most range and keeping the cost down.

BTW and FWIW, I took a long vacation, left the car plugged in in Storage mode, and IIRC the pack was at about 20% when I returned home. This was plenty to do some shopping immediately, and the next morning the pack was at a "full" Standard charge. (I had no reason to charge it immediately, so let it wait for its usual midnight start time.

A related question: How much money do you want to spend to reduce the likelihood of an event which is already extremely unlikely? If a different design would have enabled to car to sit unplugged for a year but would have raised its price by $10,000, would it be worth it to protect the car against the event that you are in a coma for two months AND your circuit-breaker trips AND you have nobody checking messages who can deal with the car when Tesla tries to notify you? I think it's a case of dreaming up extremely unlikely scenarios to justify adding a possibly expensive additional fail-safe. The guy who started all this simply neglected to plug in his car. The lesson for the rest of us: Plug in your car.

But, OTOH, if a simple software update can extend the safe unplugged time without making a different fail route more likely, then I'm all for it.

 

[dsm363]

Going forward, does it even matter?

It doesn't. I was just wondering if people with a car before #340 signed the agreement then that would make his already weak argument even weaker because his source (business partner and friend) would have signed it too.

A related question: How much money do you want to spend to reduce the likelihood of an event which is already extremely unlikely? If a different design would have enabled to car to sit unplugged for a year but would have raised its price by $10,000, would it be worth it to protect the car against the event that you are in a coma for two months AND your circuit-breaker trips AND you have nobody checking messages who can deal with the car when Tesla tries to notify you? I think it's a case of dreaming up extremely unlikely scenarios to justify adding a possibly expensive additional fail-safe. The guy who started all this simply neglected to plug in his car. The lesson for the rest of us: Plug in your car.

But, OTOH, if a simple software update can extend the safe unplugged time without making a different fail route more likely, then I'm all for it.

Well said. There really is only so much you and Tesla can do to prevent the battery from becoming ruined from lack of charge. Plugging it in is of course the first step. Anyone can imagine worst case scenarios where 5 events would need to happen for your car to lose power but as you said, at what cost? You could give your neighbor $20 to check your car once a week to make sure if was still plugged in an charging if that assurance was enough for you. There are low tech solutions to the problem if the power grid, charger, car and planet alignment all are off that day.

 

[vfx]

A related question: How much money do you want to spend to reduce the likelihood of an event which is already extremely unlikely? If a different design would have enabled to car to sit unplugged for a year but would have raised its price by $10,000, would it be worth it

Or have a 700 mile range or charge in 2 minutes or carry a sheet of plywood build a guestroom or stockpile for the coming apocalypse ?

 

[fraccy]

I just see this as an issue of relative risk. There appears to be a tiny risk of bricking it if I'm stupid enough, but I get withdrawal after just a couple of days if I haven't driven it, so the idea I'd neglect it for months on end is preposterous. I'm not remotely afraid of this happening.

A far more likely scenario is my Roadster gets written off by a lamp post or driven into by some idiot. Now that's a risk I spend effort worrying about. Next issue please.

 

[TEG]

Speaking of which - that is a real scenario - a wrecked car sitting in a salvage or repair lot with the battery/pack heading toward oblivion.
Hopefully someone (Tesla themselves?) is able to go rescue packs of otherwise disabled cars. Lets say for instance that the charge port got damaged in an accident.
Neglect and/or forgetting is one thing, but what about those rare situations where you are unable to charge even if you wanted to?