Elon Musk says Tesla has the best battery technology. I'm not sure he is right. Can anyone answer my questions?

Elon Musk says Tesla has the best battery technology. I'm not sure he is right. Can anyone answer my questions?

I've been driving a 2013 Volt for the past 10 months. Today I just emailed my order for the P85+ to tesla. The Volt, when plugged in, keeps the battery conditioned at around 86 degrees the way I understand it. I asked assistant manager questions about battery conditioning when plugged in to a charger. My concern is when it is very cold out. He tells me the battery doesn't warm up until the car is turned on. He says acceleration and regen braking is limited until the battery is warmed up. This is not like the volt. The battery is keep at a certain temperature. Can anyone verify this?

I have a thought. Maybe Telsa doesn't keep the battery warm because it would take to much energy? In the Volt the battery is more or less inside the car. So it's easy to keep warm/cool. Telsa the floor pan is a giant heatsink. So when it's -5F outside the battery heater would run constantly. Which would use a lot of energy. Especially is the car sits for a long period of time.

So I have other questions. When the car is connected to utility power and one uses the phone app to warm or cool the interior does it draw off the battery or utility power. It only makes sense to use the utility power to preserve the battery energy. But I couldn't get a for sure answer on this. And I read elsewhere that the car may draw power from the battery.

Before I bought the volt I found all kinds of technical information on how all the systems work(power train, climate control, battery, etc.) and lots of videos on YouTube. On the Tesla there is pretty much nothing. I'm thinking about trying to buy a shop manual or something to learn how the Tesla works. I hate to say this...I'm buying a $125K car with the understanding that some of the systems are not as advanced technologically as I think. Someone PLEASE prove me wrong! :)


Captain_Zap | 01. september 2013

A fairly recent firmware release changed the behavior so that heating/cooling of the battery or interior runs off utility power when the car is plugged in. The car will also heat and cool the battery when the car is off and not plugged in, keeping it within a fairly wide tolerance. The allowable temperature range is narrower for charging or driving. The result of this is that the car takes a mile or two to allow full power after a cold soak. The car does use a lot of energy from the battery to heat itself if it sits outside in subzero weather, so it's advisable to plug into at least a 120V outlet to avoid losing too much charge in an extended cold period. I assume the same is true for being too hot, but someone in a warmer climate than me needs to verify this.

shop | 01. september 2013

Yes, if the car is sitting in hot weather, the AC unit will run to keep the battery from getting too hot.

No worries, Tesla's battery management really is good.

kdeckster | 01. september 2013

The Volt doesn’t draw power to heat/cool the battery unless it’s plugged-in.

Zooomer | 01. september 2013

Anytime you are dealing with a person or a company, you merely need to look at history, ability, background to know if what they will do is any good. Elon is the gold standard. Everything he does is ahead of it's time and I don't believe GM has the ability with every brain combined to do 1/2 of what Musk can. That said, you know whatever each company does will be starkly different. GM will be near fail, Tesla will be amazing.

That being said, the volt's battery pack is ~450 pounds and gives you 35-40 miles of usable range. Tesla's battery weighs twice that but gives you 6x the range. I think that makes it pretty clear who has the better technology. Even GM's future plans for the 15 volt are pathetic compared to what Tesla released 2 years ago.

DJung | 02. september 2013

you can find stuff in the tesla blog posts. they are a little bit hidden and you have to click the red categories on the side to find them. they have information on the battery, powertrain, etc. and i would assume that some things are kept secret. and a study showed that at 100,000 miles, the battery pack for the roadster should retain 80 to 85 percent of its original capacity. Tesla says the new Model S has an improved and upgraded battery so the results for the model s should be better. this goes to show that Tesla has one of the most coddled batteries in the business (a title of one of the blog posts)

mrrjm | 02. september 2013

Thanks guys. Can't wait I get my model S.

Tâm | 03. september 2013


I know it's frustrated but battery design is one of the best kept secret of Tesla.

It's just like when you ask sales reps from Coke and Pepsi on their secret formulas. These companies has scientists galore to reverse engineer each other formulae, so they must know! But the sales reps don't or can't speak much about the formulas. That doesn't mean they don't taste good or are not addictive!

I would say that most Tesla advisors are trained on what they are supposed to say but I am not sure if they know in depth. Why don't you ask them if they remember about Ohm's law, the difference between watt and ampere...

Model S battery is well thermo-regulated to make sure it does not pose a fire hazard or to reduce the longevity of the pack.

Other companies don't have that much luck in their designs: Volt battery caught fire after a crash test, Fisker Karma caught fire repeatedly even when in parking garage, Boeing 787 Dreamliners were grounded due to battery fire...

Not a single case of fire during manufacturing or crash stages for Tesla! That spoke loudly how Tesla design has surpassed other in thermoregulation of its battery pack.

In general, the secrete is: small cells in a pack, so that if one cell fails, it's only one small portion of a pack. The pack is thermo-regulated in a closed system (just like your refrigerator compressor and radiator)

Other companies use big cells in a pack, if one fails that's a bigger portion in a pack. And it's worse in a thermo-run-away.

You can swap the entire Tesla 1,323 pound battery pack in 90 seconds and that is how well designed it is!

It is so well designed that Tesla is confident that all you can drive unlimited miles in 8 years and it will cover your 85 kWh battery pack with no question ask. No fault guarantee.

No company can do that, for unlimited miles!

Continue to ask, but it's real life: don't expect answers all the time, you might have to just look at the results and smile sometimes!

Iowa92x | 03. september 2013

Tesla drops your battery warranty if you leave it unplugged for more than 24 hours if -25 or 120 f. Other than that, don't fret it.

JZ13 | 03. september 2013

@ iowa92x - not true. Tesla changed the battery warranty several months ago so that is is a no-fault warranty. Your battery pack is now covered no matter how you use or abuse it.(except for intentional physical damage of course)

Iowa92x | 03. september 2013

That's good to hear, I checked the manual to confirm. They left the warning on battery temp, but removed the threat of warranty drop. Letting the battery sit in zero charge blows the warranty, page 25.

Tâm | 03. september 2013


The wonder of Tesla is: rules keep getting better. It's no longer user blaming. It's no one but Tesla itself takes care of the blame!!!!

Those rules that you read were obsolete. Most updated are documented by Tesla on 04/26/2013:

"Battery Warranty

The battery pack in your car is obviously very important and expensive to replace. In developing the Model S, we took great care to ensure that the battery would protect itself, always retaining a few percent of energy. If something goes wrong, it is therefore our fault, not yours.

Except in the cases of a collision, opening of the battery pack by non-Tesla personnel or intentional abuse (lighting the pack on fire with a blowtorch is not covered!), all damage is covered by warranty, including improper maintenance or unintentionally leaving the pack at a low state of charge for years on end. The battery will be replaced at no cost by a factory reconditioned unit with an energy capacity equal to or better than the original pack before the failure occurred.

The intent is to provide complete peace of mind about owning your Model S even if you never read or followed the instructions in the manual."

jat | 03. september 2013

Lithium batteries actually like it cold. However, you can't draw power quickly out of them until they warm up (which they do just by being used, due to the voltage drop across the internal resistance).

Brian H | 03. september 2013

Kind of unfair to Volt & Fisker. The Volt sat for 2 wks. unattended after a side impact crash test, and the Fiskers were drenched with salt water by Sandy. Not that Teslas wouldn't have done better in the same circumstances, but ...

Tâm | 03. september 2013

March 2012: Consumer Reports' Fisker Karma broke down due to faulty battery

Fisker Karma was in the user-blame mode in Sugarland, TX fire and "implying fraud or malicious intent were open questions. "

Editor's note: Autoweek received the following statement from the attorneys representing the Fisker Karma owner, Jeremy Gutierrez. The statement is reproduced below.

Houston, Texas, May 9, 2012 – On the afternoon of May 2, 2012, Mr. Jeremy Gutierrez's brand new Fisker Karma hybrid electric vehicle caught fire while parked in his garage, setting fire to his home while his wife, mother, and child were inside. Thanks to the fast action of Mr. Gutierrez, he was able to evacuate his family from the home moments before portions of the house were engulfed in flames, including his child's bedroom.

The Fort Bend County Fire Department immediately responded to the scene and as able to contain and extinguish the fire before total destruction of the Gutierrez's family home. The fire department recently completed their investigation and determined the origin of the fire was, in fact, Gutierrez's newly purchased Fisker Karma hybrid electric vehicle that he just took possession of two weeks earlier. Chief Investigator for the Fort Bend County Fire Marshal's Office Robert N. Baker has concluded that the fire was accidental in nature.

Since the date of this incident, Mr. Gutierrez has been fully cooperative with public safety officials, as well as insurance adjusters and the vehicle manufacturer's investigators. In fact, Mr. Gutierrez fully accommodated the precise and somewhat peculiar demands of Fisker Automotive, who sent their self-proclaimed “SWAT Team” of engineers and inspectors (that included their own forensic cause and origin investigator) to the Gutierrez home within 24 hours of the fire. They descended upon the Gutierrez home in alarming numbers and immediately demanded a 24-hour lock-down of his home, including the remains of the Fisker Karma vehicle. They also cordoned off portions of the Gutierrez home with non-transparent tarps to block the view from the public. Fisker even had access to eyewitnesses, who were interviewed by Fisker investigators and those investigators were shown video footage of the Fisker vehicle on fire before and other part of the garage. Mr. Gutierrez accommodated every request with the hope of have a full, fair and open inquiry into the cause of the Fisker vehicle fire that set his house ablaze and endangered his family.

Despite the fact public safety and law enforcement officials have determined Mr. Gutierrez's home and vehicles are not a crime scene, Fisker Automotive released a public statement on May 8, 2012 implying fraud or malicious intent were open questions. The family is stunned by this implication. The Gutierrez family has afforded every accommodation to Fisker and access to all evidence that public safety and law enforcement official examined. Fisker's statement is a grave disappointment, especially in light of the damages the family suffered and continues to suffer.

The Gutierrez family has suffered enough. They are temporarily displaced from their home, and have lost three vehicles. They value their privacy and wish to have this investigation completed immediately so they can return to their home. The law firm of Johnson, Trent, West & Taylor, L.L.P., a Houston-based law firm, has and will continue to represent the Gutierrez family during this time. Please direct all inquires on the matter to our firm; do not contact Mr. or Mrs. Gutierrez directly. Attorneys for the family, Lori Hood or Rafe Taylor, can be reached at (713) 222-2323.

jat | 03. september 2013

@Tam - I believe all the Fisker fires (aside from the ones with Sandy damage) were due to a short in a unfused cooling fan (the only fuse was the main fusible link to the battery, so it was more than enough to melt the small wire feeding the fan - I'm no EE, and I know that is a really bad idea). The CR battery problem was recalled due to assembly issues at A123, and had nothing to do with any fires. The poor customer relations are no reflection on the batteries themselves, and a disinterested observer might see parallels with the Roadster "bricking" stories a few years back.

Fisker (and their customers) already have enough problems - no need to fabricate more. Making people scared of EV batteries in general does nothing to help EVs, even those that have had no battery issues.

Captain_Zap | 03. september 2013

@Brian H

Some Teslas were immersed in brackish water in Florida. They didn't like it much but it didn't reduce the cars to charcoal.

Brian H | 04. september 2013

Yes, the TM design is far more bullet-proof. No question.

AmpedRealtor | 04. september 2013

@ mrrjm,

When plugged-in, the Model S actively cools and heats the battery as needed using shore power. If your car is plugged in when it's cold, the battery should be maintained at the proper temperature and all features (including regen) should be available the moment you drive away. However, when unplugged, the car does not actively manage the battery's temperature. This is why Tesla says that a plugged-in Model S is a happy Model S.

Pre-conditioning when plugged-in presumably uses shore power, while it will use battery power when not plugged-in. Pre-conditioning when not plugged in will also condition the battery to the proper temperature. | 04. september 2013

So, an interesting question: when you are using the charging timer (i.e. don't start charging until midnight because of ToU etc), does the Tesla still tap shore power for battery heating/cooling a) before the timer kicks off or b) after charging is complete.

Or will the Tesla only tap shore power during the window between when the charging timer kicks off and when charging is complete.


AmpedRealtor | 04. september 2013

@ omarsultan, I would speculate that shore power is used regardless. I tried a timer-based charge yesterday. While the car was waiting for 7:05pm to roll around, I had the door open and the AC running. The display showed it was drawing shore power and the green light at the charge port was blinking rapidly even though the car was not charging.

Brian H | 04. september 2013

Good test.

jat | 04. september 2013

@AmpedRealtor - that is supposedly a feature of the 5.0 release. I know in 4.5 I have definitely had it plugged in, started the AC, and it didn't draw any power from the HPWC because the battery was already full.

negarholger | 04. september 2013

I am 4.5 and it draws power from the outlet if plugged in. Come home plug in with charging set at 12:05. A little later come back forgot something open door A/C starts and car draws 2kW from the outlet. Green light blinking, close the door lock the car and after couple of seconds A/C stops and light turns to dark blue.

shop | 04. september 2013

@Amped, the car most definitely does actively manage the battery's temperature when unplugged. Why do you think it doesn't?

Brian H | 05. september 2013

AFAIK, the parked temp mgmt kicks in only in extremes (deep freeze, very high temps.) Not to optimize for start/driving.

Mathew98 | 26. november 2013

@Smith - Can you troll in the Chevy forum? Can you take your minimum wage job and troll somewhere else?

If an object impale your ICE vehicle on the road at 70+ mph, would you be able to walk out of the car unscathed? If you crash your ICE into a concrete wall at 120 mph, would you survive the myriad internal injuries from the crash?

Are you insinuating that these batteries will catch fire on its own? Statistically speaking, you're an idiot!

Jewsh | 26. november 2013


"Three Tesla battery fires later, Tesla batteries are statistically more dangerous then Chevy Volt batteries. A fact that trolls hate."

Probably best to wait for the NHSTA to conclude their investigation, particularly given that the variables are far too small to conclude anything.

Jewsh | 26. november 2013

@ Smith 1:

We've had a nobel prize winning physicist explain to us how unreliable our statistics are. I'll take his word versus yours, thanks.

PatT | 26. november 2013

I believe Elons comment about not recalling the MS due to those fires is being misinterpreted. Tesla can recall the car if they choose to but he did not see a reason to do that. In that interview he pointed out that TM had recalled some early MS for a seat belt issue. They did that voluntarily.

Actually NHSTA can not recall any car -- they can only recommend that the manufacturer do that. At the time of the interview, and even now, NHSTA has not recommended a recall.

rodhoffman | 26. november 2013

Go away Smith 1 we know who you are and being Mr. Negative is getting old. Owners - flag this guy and send him away.

Jewsh | 26. november 2013

@Smith 1:

"So a Nobel physicist indicated that he and his field are unreliable because they are based on statistics? lol In case you haven't noticed the Nobel Prize has lost its credibility and has become a joke in recent years."

That's right. When we've got you on the run, change the focus of the argument and deflect.

Reflect on what you just said, then go away.

PatT | 26. november 2013

@Smith: So what would you have TM do for when they recall the Model S? What fix do you recommend?

Skotty | 26. november 2013

The statistics speak for themselves only in saying that there is insufficient data for the statistics on this issue to be in any way meaningful.

PatT | 26. november 2013

In other words -- the statistics are meaningless. I think that is the point!

oildeathspiral | 26. november 2013

Smith 1

1. Are you currently or have you ever been long or short tsla stock or options whether directly or indirectly?

2. Have you been in contact with or plan to contact any law firm that is currently investigating or suing Tesla?

3. Are you a current or former member of NADA or any similar organization?

4. Since you're not a Tesla owner and don't appear to be an enthusiast, what is your interest in Tesla and why are you here?

AmpedRealtor | 26. november 2013

@ Smith 1 - What is your point?

Jamon | 26. november 2013

You guys need to stop engaging the troll. It won't accomplish anything.

jkn | 27. november 2013

@ PatT

Statistics with too small sample size are almost meaningless. After some years and more MS burns, statistics will become meaningful. Now with only 3 fires, stats are not reliable.

Tesla fires so far have been a PR problem, not a safety problem. Fire starts slowly, so people have time to exit and call fireman. ICE car can burn so fast that your family dies before you can stop and open doors.

@ Smith 1

You are asking for an investigation. NHSTA is investigating. Don't you trust them? Who should investigate? This forum? Me?

What cover up? What is being covered up?

David70 | 27. november 2013

Just ignore him, as already said. He's contributed nothing new or meaningful. There's never been a safety issue. At the worst, it's only damage to the car.