Do you know that you must keep your battery charged?

[JRP3]

My guess is that Nissan simply disconnects the pack from all drains after a certain low SOC is reached, and there is almost zero self discharge from the cells at that point. Part of the difference is that Nissan uses more stable lithium chemistry than Tesla does so it doesn't need as much active management. There is a price to pay for the higher energy density of LiCo cells.

 

[dsm363]

The fact that the car can become a 'brick" you NEED to know BEFORE you buy the car. NOT after. It is not a toothbrush you are buying here.

You do know now though so what's the problem? You have a year probably to think about this and plan ways to prevent this from happening. Again, this can only happen if you purposely try or just ignore every warning the car gives you. If you plug in every night, it's not a problem. As to the airport problem, many people could save money but taking a taxi or town car to the airport instead of paying for long term parking (if your trip is greater than two weeks) if the cab ride x 2 is less than the parking. It wouldn't be an issue for those people. For other people, they would need to plan ahead. Driving an EV does require a little more thought at the moment but in the future, probably every spot will have some sort of plug in the long term parking lot making this a non-issue.

 

[qwk]

Well, I've been here since 2009, and as mentioned, until this story, I did NOT know that the pack could be essentially killed. I knew keeping a high charge or a really low charge could reduce battery life, but did not know staying at 0 killed the battery. I'm not a Roadster owner though, so if they were told at purchase, then great. It's apparently NOT obvious though (unless you understand how lithium ion batteries work -- does the general public?)

Most of the general public can't even change a flat tire. All they know is how to swipe a card, and put a nozzle in the side of the car.

 

[Fr23shjive]

Most of the general public can't even change a flat tire. All they know is how to swipe a card, and put a nozzle in the side of the car.

EXACTLY. And Tesla expects them to read their manual and understand that their car can't go completely uncharged? It's not going to happen and Tesla should know this. They need to take steps to prevent this from happening or there is going to be a backlash once the Model S is in full production.

 

[AnOutsider]

Most of the general public can't even change a flat tire. All they know is how to swipe a card, and put a nozzle in the side of the car.

Ok then, in your snark, you just proved yourself wrong. It's clear , that to the general public, what you stated is NOT "obvious".

As an aside, I read the letter -- it seems pretty reasonable up until the last 2-3 paragraphs. Then it begins to sound like a veiled threat -- no good. He does raise some good points though. If 5 out of 2,000 or so roadsters had the problem, then it's only going to be worse when there's 20,000 Model S's on the road in the first year or so.

So Tesla should continue to make it very clear (and "obvious") that if the car sits longterm, not charging, they can basically kill their battery. I think the more the public fully understands this, the less incidents there will be.

I still think they should also go a step further and kill the battery draining systems at say, 2-3% SoC. I guess some more technical types can guesstimate at the time until 100% dead from there.

 

[eledille]

Exactly. Cut the draw when things get too low. It would seem simple? Nissan apparently does it...

Ahum. Think did it in 1998, to avoid a USD 1000 repair.

A) Tesla should make sure the car hibernates at some low SoC because it's a simple fix.
B) This is blown out of all proportion, but it should be fixed anyway.

 

[Norbert]

Well, I've been here since 2009, and as mentioned, until this story, I did NOT know that the pack could be essentially killed. I knew keeping a high charge or a really low charge could reduce battery life, but did not know staying at 0 killed the battery. I'm not a Roadster owner though, so if they were told at purchase, then great. It's apparently NOT obvious though (unless you understand how lithium ion batteries work -- does the general public?)

I've read it *many* times here, explained as clearly as necessary, even though I'm in general more often reading the Model S threads than the Roadster threads.

 

[ckessel]

EXACTLY. And Tesla expects them to read their manual and understand that their car can't go completely uncharged? It's not going to happen and Tesla should know this. They need to take steps to prevent this from happening or there is going to be a backlash once the Model S is in full production.

Yea, somewhere I mentioned idiot proofing it. It's reasonable to expect folks to take care of the charging issue, but it's not the reasonable people that are going to hit this and scream to high heaven. It's in Tesla's interest to idiot proof to prevent the PR damage.

 

[stopcrazypp]

I knew keeping a high charge or a really low charge could reduce battery life, but did not know staying at 0 killed the battery.

You've never had a car battery need replacement from being left uncharged for long periods of time? Incidentally if this have never happened in your life, that does reduce your chances of this being an issue (means you rarely keep your vehicle unused for long periods of time).

 

[qwk]

EXACTLY. And Tesla expects them to read their manual and understand that their car can't go completely uncharged? It's not going to happen and Tesla should know this. They need to take steps to prevent this from happening or there is going to be a backlash once the Model S is in full production.

How many people have you met that haven't ever plugged an electrical cord in? It's not like they have to get out and pull off the tire or the battery will go dead. I was just illustrating ignorance of current ice cars, which have had no problem in adoption. Almost Everyone has one.

 

[AnOutsider]

You've never had a car battery need replacement from being left uncharged for long periods of time? Incidentally if this have never happened in your life, that does reduce your chances of this being an issue (means you rarely keep your vehicle unused for long periods of time).

Correct. Though, we are a 2 driver household with 3 cars. It's not uncommon for one of them to sit for a couple months unused. No dead batteries or other issues. I did however, take steps to prevent the tires on my R8 from flattening while sitting during the winter months. Of course, crappified tires != 40k battery

 

[qwk]

Ok then, in your snark, you just proved yourself wrong.

Huh? So if you buy a brand new ice vehicle, run it out of oil until it dies, do you think it will be covered under warranty? Ignorence is no excuse. I was just illustrating that people's ignorance hasn't stopped them from driving ice cars. Why would it be any different with EV's?

 

[NigelM]

So far though, it would seem it's the battery management systems and perhaps connectivity? So, again, if those systems can be shut down at a critical point as to not fully deplete the battery, then why not? Stopping the systems keeping a battery at a certain temp has to be a better option than draining the pack completely? Especially if it means the pack lasts longer.

Correct. But, if you stop the auxiliary draw at a minimum level and you still don't plug-in for an extended time then your battery pack will self-discharge that last couple of %. You're still not going to avoid the issue of leaving a battery without a charge supply. Set the minimum level at a higher percentage and there will be many more complaints from owners fearing cell damage as the battery management systems go out.

Truth be told, we pretty much all know that this can happen to batteries whether it's in a flashlight or a laptop; it only sounds scary when we realize that it can happen in a $90k car.

 

[NigelM]

...we are a 2 driver household with 3 cars. It's not uncommon for one of them to sit for a couple months unused.

No offence...that's a poor use of capital. You should sell one and buy some TSLA.:wink:

 

[stopcrazypp]

For all the people suggesting to "cut the draw" at some point, has it even been verified the Roadster doesn't do that at some point (I know when the Roadster says zero, there's actually a few hundred millivolts left before the actual zero)? Are people willing to completely give up a couple percent of battery capacity to just for people unaware of this issue? I certainly won't be willing too (I hope it is at least toggle-able, like Range/Standard mode is).

 

[qwk]

Truth be told, we pretty much all know that this can happen to batteries whether it's in a flashlight or a laptop; it only sounds scary when we realize that it can happen in a $90k car.

Exactly.

 

[Tommy]

Yea, somewhere I mentioned idiot proofing it. It's reasonable to expect folks to take care of the charging issue, but it's not the reasonable people that are going to hit this and scream to high heaven. It's in Tesla's interest to idiot proof to prevent the PR damage.

As a commenter on another forum noted "There is a constant race between making something idiot proof and the universe making better idiots".

 

[donauker]

Fully recharge it until you leave if it's not possible to plug it in. The Roadster manual says worse case, it'll last about 11 weeks (almost 3 months) if it is fully charged. Legally the owner is responsible because the manual and warranty clearly says not to leave the car unplugged for long periods of time.

It appears that everyone would expect to be able to park their vehicle safely for some number of weeks. Many of us have experienced very low levels of loss over a number of days to several weeks. Some people may never think of the huge impact that a different storage location might have.

I have a storage unit that I have stored ICE vehicles in over the past years. I would not be surprised to discover that storing my Roadster there for even a week or two during a summertime heat wave would destroy the battery. These metal enclosures become veritable ovens in the summertime sun when the temperature approaches 100 degrees. The active cooling of the battery by the AC unit as the car tried to maintain a safe battery temperature would just displace the heat into the small enclosure, just to be reabsorbed by the battery.

 

[AnOutsider]

Huh? So if you buy a brand new ice vehicle, run it out of oil until it dies, do you think it will be covered under warranty? Ignorence is no excuse. I was just illustrating that people's ignorance hasn't stopped them from driving ice cars. Why would it be any different with EV's?

The post I was referencing:

You have been here since at least 2009 and still didn't know any of this? Talk about not paying any attention to the obvious.

i.e. that this is NOT obvious. If it isn't OBVIOUS to a person posting here for 3 years, it sure won't be to the average joe who also can't change a tire as you say.

Correct. But, if you stop the auxiliary draw at a minimum level and you still don't plug-in for an extended time then your battery pack will self-discharge that last couple of %.

Right, but that will then be a "natural" death, not death by Tesla It's like my heart rate example above. Instead of your heart racing until the very end, it begins to slow down and thus your body gets by on less and less resources. You eventually die, yes, but you live longer.

it only sounds scary when we realize that it can happen in a $90k car.

This is true, but we're talking about how fear, uncertainty and doubt like this can damage the adoption of EVs and/or hurt Tesla. So sounding scary is enough to do that!

No offence...that's a poor use of capital. You should sell one and buy some TSLA.:wink:

I did, and sold remember My inner speed demon says it's been an excellent use of capital

For all the people suggesting to "cut the draw" at some point, has it even been verified the Roadster doesn't do that at some point (I know when the Roadster says zero, there's actually a few hundred millivolts left before the actual zero)? Are people willing to completely give up a couple percent of battery capacity to just for people unaware of this issue? I certainly won't be willing too (I hope it is at least toggle-able, like Range/Standard mode is).

Nope, haven't seen it confirmed one way or another, but the general tone seems to be that Tesla doesn't cut their draw at a certain point.

 

[ckessel]

Are people willing to completely give up a couple percent of battery capacity to just for people unaware of this issue? I certainly won't be willing too (I hope it is at least toggle-able, like Range/Standard mode is).

I think there's a happy medium on this. If you get down below 5% it pops up a warning and says auto shut off at 2% charge for battery protection unless you override by clicking "here". So, if you're in the car and want to keep going that's fine, but if the car is unattended then it'll disconnect itself and keep it safe.

* 5% and 2% picked for illustrative purposes and not intended to reflect actually useful numbers.