Do you know that you must keep your battery charged?

[JRP3]

Yes they must have some buffer at the top and bottom. One of the big problems with going to zero SOC is that the cells are probably top balanced. Finishing charge voltage is used to balance the cells when full, since cells are of slightly different capacity that means they are unbalanced at the bottom. Think of lining up a bunch of sticks of different lengths, you can line them up so they are all even at the top but they are uneven at the bottom, and vice versa. Top balance means on a deep discharge some cells end up closer to zero than others, and if a few hit zero under load they go into reversal and are ruined. Since I'm not using a BMS on the pack I chose to bottom balance my cells, so they all discharge to the same SOC level and even a deep discharge can't drive any single cell to zero and reversal under load. I leave a little more room on the top and stop charging early to compensate, giving up a couple miles of range.

 

[markwj]

I realize that this is the thread that won't die, but I just bricked my roadster. Damn.

It is a 2008 radiant red, and the kids were last to use it. They must have driven it to 0% SOC then put it in storage, because when I looked at it today it was completely dead. It won't start or drive, and has been in storage for about 4 months. I'm pissed, and there is no way I'm letting the kids drive my roadster unsupervised again.

2 out of the 5 cells in the pack won't take a charge at all, and the other 3 are probably ruined - they are taking a _long_ time to charge. Replacements for just those 2 cells are probably gonna cost me 15% of the price of the car - and if the other 3 are ruined I'm looking at a bill of close to 40%. The only good news is that the remote seems fine.

Tesla Roadster - Tesla Motors

 

[AnOutsider]

Had me going

 

[mpt]

LOL, had me there too.

 

[daniel]

Me, too. Whew!

 

[JRP3]

Does it use lithium cells?

 

[markwj]

Does it use lithium cells?

Eneloop NiMH AA rechargeable. Supposed to be low self-discharge - they quote 25% loss over 3 years for latest version.

 

[dsm363]

There's something called OVMS out there. You should have installed that and you would have gotten a warning about the low SOC. Did you even read the manual?:smile:

 

[VolkerP]

I just bricked my roadster. Damn.

You made my heart stop for a moment :scared:
Oh, well, have to brush the dust off mine. It died several months ago. Replacing the batteries cannot be expressed in percent of vehicle purchase price since it was in the Tesla schwag pack :smile:

 

[widodh]

I realize that this is the thread that won't die, but I just bricked my roadster. Damn.

It is a 2008 radiant red, and the kids were last to use it. They must have driven it to 0% SOC then put it in storage, because when I looked at it today it was completely dead. It won't start or drive, and has been in storage for about 4 months. I'm pissed, and there is no way I'm letting the kids drive my roadster unsupervised again.

2 out of the 5 cells in the pack won't take a charge at all, and the other 3 are probably ruined - they are taking a _long_ time to charge. Replacements for just those 2 cells are probably gonna cost me 15% of the price of the car - and if the other 3 are ruined I'm looking at a bill of close to 40%. The only good news is that the remote seems fine.

Tesla Roadster - Tesla Motors

Mine is still working fine: http://www.youtube.com/watch?v=cyar4yrXCVg

 

[DrTaras]

Ferrari 458 Manual

If this thread has taught us anything is that you must read and abide by the rules set out in your manual...From the Ferrari 458 Owner's Manual:http://jalopnik.com/5893895/the-ten-strangest-things-found-in-car-owners-manuals/gallery/11

 

[Raffy.Roma]

While there are some truths in this blog, there are also some mistruths. 1. Voltage in Japan, 2. Knowledge that you should not plug in with an extension cord. 3. Parking the car with a discharged battery for an extended time, and more.....

The problem with this type of blog is that there is no effective means of refuting the basis of the post. Some contact should be made to assure that this does not become an issue for new buyers. Like an ICE, you can't run the car without oil or coolant, or damage will result. With an electric car, you can't leave the car in a discharged state, or damage will result. New owners should b e aware. It would be great if there were a procedure to attempt to recover "damaged batteries"

ok I must leave the car charged. But what should be the SOC percentage? 80%? 90%? or 100%?

 

[JRP3]

I'd use 80% SOC.

 

[Zythryn]

ok I must leave the car charged. But what should be the SOC percentage? 80%? 90%? or 100%?

Doesn't matter too much as long as it never goes to 0%.
The healthiest for the batteries is around 50%. 100% will put strain on the batteries. But 0% is deadly.
If you are storing a Tesla, Tesla recommends using the storage mode for the roadster (which charge to around 50% and keeps doing so as needed). I believe the recommendation for the Model S will be to us the standard charge mode. Note, I have not seen the owners manual yet, so that is just a guess at this point.

 

[GSP]

EVs should not only be charged when parked for hours or days, but also plugged in. It may be acceptable to leave your model S unplugged at the airport for 2-3 weeks, but be sure you make it back on schedule. If you were to be detained overseas, someone will need to rescue your car. Better to leave it plugged in and take a cab to the airport.

80% SOC is good if you plan to drive the car, but 50% SOC would be better for long term storage (weeks or months). Tesla offers "standard mode" charging and "storage mode," with SOC levels pre-set by Tesla engineers.

GSP

 

[dsm363]

EVs should not only be charged when parked for hours or days, but also plugged in. It may be acceptable to leave your model S unplugged at the airport for 2-3 weeks, but be sure you make it back on schedule. If you were to be detained overseas, someone will need to rescue your car. Better to leave it plugged in and take a cab to the airport.

80% SOC is good if you plan to drive the car, but 50% SOC would be better for long term storage (weeks or months). Tesla offers "standard mode" charging and "storage mode," with SOC levels pre-set by Tesla engineers.

GSP

I agree. If you're gone on a really long trip it may be cheaper and faster to take a cab anyway than pay $10-20/day long term parking. Tesla has said the Model S can sit for a year at 50% SOC but I'd just do a full standard charge before heading to the airport assuming I'd have enough to cover sitting there unplugged and to make it back.

 

[Dave EV]

EVs should not only be charged when parked for hours or days, but also plugged in.

Depends a lot on the specific EV. For example, if you leave your LEAF plugged in for 2 or more weeks, it's quite likely that you'll come back to a dead 12v battery unless you start with a low charge and set up a charge timer so that the car charges at least 30 minutes. Apparently there's an oversight in the firmware which keeps the HV battery from charging the 12v battery sufficiently in that situation. No thermal management system - so no need to leave it plugged in to keep the battery conditioned, either.

I thought that the S would tolerate months without being plugged in without issue as long as it had a decent charge to start with?

Having a "vacation mode" for most EVs would really seem to make sense where one could program the car to maintain a low SOC - calendar life of lithium batteries can be extended significantly by storing at low SOC instead of high SOC. Kind of makes me wonder why on a car like the S with a huge battery why they might not have a 50% "regular" charge level for daily use or something else besides standard/range modes. I imagine that for typical use one is probably only going to use 10% of the total capacity. Maybe the benefit isn't all that big compared to storage at 80% or whatever the regular charge stops at - but the data I've seen typically indicates at least a 25% improvement in calendar life - I imagine that many people would use it if given the opportunity.

 

[JRP3]

I chose 80% for a number of reasons if the car will be left unplugged. 80% is low enough that extended time at that SOC will not impact the battery much, and over time the SOC will drop. It also provides enough energy for the pack to power temperature control for a while if needed when not plugged in, ( or if plugged in but power is lost). Since the S will go into a sleep mode when the pack SOC drops low enough it seems quite safe to leave the vehicle for extended periods not plugged in, I think Tesla says up to a year now, so you could get away with leaving it at an even lower SOC, but at some point you'll be without temperature management. If you're in a climate where that is not a concern then you don't have to worry about it.

 

[mlascano]

Not sure if this has been posted on TMC so cross posting from the TM boards.
Rod and Barbara who took delivery of their Founders car a while ago have confirmed the Model S does not have a Storage mode, only Standard and Max. Link

Rod and Barbara | August 30, 2012
Butch asked on Aug 18 if the Model S has a Storage mode of charging like the Roadster. The Model S Guide for Owners and the touch screen only have two charging levels: Standard (85% of battery capacity) and Max Range (100% of battery capacity). We checked with the Tesla Ownership Experience team and they confirmed there is no Storage mode. If the Model S is to be left unattended for a prolonged time period it is supposed to connected and charged in Standard mode.

 

[wiztecy]

If I was letting my roadster sit for a week or more without any use I'd leave the SOC at 50%, hook to the charger and let it sit in storage mode. In storage mode the car wakes up once a day to check the SOC. I forget the SOC that storage mode keeps the care in, 20-30%?... (it may take your starting SOC and divide that by half, so if we started at 50% it will wait until 25% to charge) but it will kick on if it need to add a charge plus it its hot the roadster can handle the hot days better plugged (with its thermal management system) than unplugged.