Panasonic 18650B has long been available

Panasonic 18650B has long been available

I believe Tesla uses 18650A which is about 10% less in capacity and has already known this "new" product.

Will Tesla beef up battery packs? Any insiders' news?

Whity Whiteman | 26 novembre 2012

I remember an article 6 months ago about the new generation of panasonics 18650.
This article describes an increase of 57%. So, this accus are there. The article mentioned, that this cells go in production late 2012.
What I imagine/wish, is a 750KM-range with this new gen of cells.

Timo | 26 novembre 2012

There should be silicon-based over 4Ah battery coming from Panasonic rather soon. It's heavier than 3.1Ah one (even relatively), but it takes quite a lot less space for same capacity. AFAIK it should have been in production this year, I have no clue why it has been delayed (maybe capacity drops too fast?).

blackscraper | 26 novembre 2012

Silicon based lithium-ion battery has lower voltage, so it is not increasing capacity proportionate to mah number. I was hoping Tesla, as a pioneer, would adopt this new battery ASAP, although such action would harm sales of existing products.

Timo | 26 novembre 2012

Generally speaking, yes, but not for that particular battery. It was something like 3.5V which is only 0.1V less than NCR-18650A.

hfiennes | 26 novembre 2012

Pretty sure there's a long qualification process that Tesla perform before they switch cell chemistry; likely 12+ months of testing are needed - electrical, safety, long-term performance, temperature, etc.

One of the things that takes a long time with battery testing is cycle life; li-ion cells tend to swell as the cycle count increases and amount of swell is usually pretty important in the mechanical support design, plus you want to know exactly how capacity will be affected by *your* typical charge and discharge profile. Unless you use unrealistic load and charge profiles, you really can't short-cut this process - you need to put the hours in... many, many thousands of them.

Any information you get from this process may result in a design change to the cell... which is then a total reset of your testing cycle. It's one of the few things that more money can't help with, unless you can buy a time machine.

Vawlkus | 27 novembre 2012

Tesla has this far only been using proven batteries, not experimental ones. They can't afford a battery recall like Fisker had.

Timo | 27 novembre 2012

Neither does Fisker. It's actually surprising that it is still alive (somewhat).

blackscraper | 27 novembre 2012

I don't believe Panasonic has released an "under-test" product, Vawlkus. I'd rather think Tesla won't adopt this 3.4AH battery for one or both of the 2 reasons:

1. The battery has yet to prove itself on Model S
2. Harm to sales of existing products.

Let's hope Tesla would not bury too deep in the money issue by postponing technology advances.

Tiebreaker | 27 novembre 2012

I don't think #2 is the reason, Tesla doesn't sell batteries. The battery pack is sealed, you won't know what is inside. If you are referring to the whole pack, in terms of increased total capacity, then #1 is the most likely reason: they cannot just change the batteries, but the whole battery management system needs to be adjusted: charging, discharging, temperature management, control software...

blackscraper | 28 novembre 2012

TieBreaker, I am in high-tech industry too. Most of time, comercialise products is not that difficult. It's true TM does not make and sell battery, but TM sells products integrated with single battery which is a product of another company. Actually, the most valuable technology TM sells is the battery management system. So in the case when new battery comes into market, TM has the financial reason NOT to integrate/develop it with their manage system since TM has existing products which sells well and Panasonic has not yet phased out 18650A. Remeber, in this market, TM has monopoly though.
If I were TM, I'd rather develop "new" vehicle than use new battery

ManuVince | 28 novembre 2012

Hum, Tesla only buy the individual cells to Panasonic not the whole battery, and I think you underestimate the amount of engineering that went into the way those cells are arranged and wired together in the battery, that's actually one of Tesla most protected secret. Changing the weight, power density, power output of the cells would have a major impact on their design, and would indeed need extensive testing.

blackscraper | 28 novembre 2012

What I am worrying is, Tesla is not even looking into replace 18650A with 18650B or other more advanced products. TM just does not want to do it as TM does not have any valid competitor in this area. That is my concern...

From what TM is doing right now, TM is more focused on making more money and proving itself to Wall Street than making better products. Whatever it is trying to roll out in the next few years are more of a product based on existing platform than an "innovation" like it used to do.

Volker.Berlin | 28 novembre 2012

blackscraper, what is your allegation based on? I agree that it's a problem if Tesla really doesn't look into using new cells. However, based on their track record, their stated mission, and their attitude so far, I'm not worried. Just because we don't see them working on it, it doesn't mean they aren't working on it... Call me naive, if you like!

blackscraper | 28 novembre 2012

Well, everybody holds his/her own belief. While I won't call you naive, I will call myself pessimistic, pessimistic about cooperations or namely, the All-Mighty Dollar. I have seen so many startups, while full of ambitions when really small, became money makers soon after they gobble up a piece in the market. And the only thing that matters, is how to make more money. I sincerely wish I am wrong. I really hope Telsa is not and will not be one of them. Take a look at Google, this Mountain View based star company continues its enthusiasm in technology. I have seen the same thing in TM when it was still working on Roadster, but do I see it right now? NO!

What is my allegation based on? When a company releases its own technology like squeezing the last drop of toothpaste out of a tube, like most Japan companies are doing right now, it has finished its own standing point as an "inventor". This is what I sense from TM these days. maybe I am wrong, correct me if you can and I really hope I can be corrected and convinced.

Nexxus | 28 novembre 2012

+1 VB

Coming from an engineering background I'm sure EM has his best electrical engr's on this and as one of Panasonics largest customers (IMO) I'm sure they've delivered any new batteries they've come up with to TM for testing to see how they can be used in future models (Model S 2.0, Model X, GenIII, etc...).

As an electro-mechanical engineer I can attest to the time and effort it takes to get Li-Ion batteries tested and certified for use. I work for a rocket manufacturer in their engineering department and we have to constantly test the Li-Ion battery packs we use for flight to support the avionics section of our rockets. Any new footprint for the battery (e.g. - larger/smaller, higher voltage/density, lighter/heavier, etc...) has to be qualified to some pretty high standards. While maybe not as high as space flight standards, I'm sure TM needs the batteries they receive to be tested to some high level otherwise they woulddn't warrant them for 8 years.

Technology doesn't stop with one product/platform. I'm sure they're on to developing the next gen battery packs for the future.


Tiebreaker | 28 novembre 2012

@vb +1

@wdazew +1. Confirms what I said above. I am an EE, and Although I don't work on hardware, that is exactly my knowledge of the process.

mrspaghetti | 28 novembre 2012


Whatever it is trying to roll out in the next few years are more of a product based on existing platform than an "innovation" like it used to do.

Talk about not giving people a break. Tesla is still rolling out its breakthrough product (maybe 1000 delivered so far) and you're already accusing them of slacking? Damn, glad you're not my boss or my parent...

Tiebreaker | 28 novembre 2012

@blackscraper - Google is a really bad example. It has become one of the biggest money grabbing machines. See their new privacy policy: they will use everything they know about you to make money. They will use every tech to get to know more about you, from every device you use. Yes, they have an enthusiasm for new technology, as long as it translates to $$$$.

blackscraper | 28 novembre 2012

I have got what you guys said from other professionals. Maybe I am too pessimistic as what TM will become and again I reiterate, I hope I am wrong. and Let's hope I am wrong. We will see in another year or so.

mrspaghetti | 28 novembre 2012


Without the incentive of $$$$, few innovations would occur. If Google management were not interested in making money, the company would not have advanced technology as it has. Making money and doing good are not mutually exclusive.

I'd be interested to hear if you're aware of anyone who has been harmed by the collection of information by Google. Conversely, I wonder how many cumulative millions (billions? More?) of hours have been saved by people all around the world by the advancements in search (and other) technologies such data collection has enabled.

DouglasR | 28 novembre 2012

This reminds me of the scene from "Portlandia" where the guy is riding around on his bicycle yelling, "Whole Foods is corporate!"

Brian H | 28 novembre 2012

IIRC, Elon has projected/promised much more advanced batteries for GenIII, which suggests TM already has some new tech/chemistry in qualification. And, as he also has said, the GenIII is where the real action will be; if TM could have gone straight to that product, it would have. But it takes about 3 rounds of iteration before the tech is solid (and of course you have to hit the ground running with a high volume product, otherwise the economies of scale don't apply, and costs kill you.)

Tiebreaker | 28 novembre 2012

@mrspaghetti: of course you need $$$$ for innovation. I am a free-marketeer. Just Google is not exactly the shining example of a benevolent giant doling out technology goodies to the masses, as opposed to Tesla Motors.

Tiebreaker | 28 novembre 2012

p.s. (hit submit too soon)
I am typing this in a Google Chrome browser, even the iPhone, after using Google search, with a Google gmail email, found it on Google maps, etc etc... all good. I didn't say anybody was harmed by Google. Just that Google's enthusiasm for technology is $$$$ driven. So is Tesla's. Anyway, it irks me the insistence that TM is not using the battery just to sock us all, and not seeing any other reason.

mrspaghetti | 28 novembre 2012


I wouldn't invest in any company that "doled out" anything. You say you're a free-marketeer but your comments make me think your definition of that doesn't match mine.

Tiebreaker | 28 novembre 2012

@mrspaghetti: I think you are reading it wrong. However, we can agree to disagree.

mrspaghetti | 28 novembre 2012


Works for me. And I think we probably do agree that neither Tesla nor Google is perfect, but regardless I'm a fan of both.

Tiebreaker | 28 novembre 2012

@mrspaghet: I agree that here we do agree. :-)

See this:

mrspaghetti | 28 novembre 2012


Love it!

lph | 28 novembre 2012

If Tesla did up date their battery pack with every small incremental increase in cell capacity, I would pull out of investing in them. But I think that they are smarter than that, and so far Elon seems to me to be really smart in this area. This is partly because they are up against ICE vehicle makers from all over the world, and Tesla needs to use the resources they have to maximum benefit. Remember that the general public is not on board with electric cars yet.

IMO the smart thing is to upgrade the battery pack when the cells have obtained say a 30%-50% or so in energy and preferably power as well. As Brian H indicated the appropriate time would seem to be when Gen III cars come along. This way the same platform can be updated and mass produced for all the cars in the product line thereby obtaining maximum cost savings using economies of scale. Also this can be used as a further marketing tool to wow the public.

Further if the battery packs were updated every few months it would not bode well for Tesla selling the cars since many would cotton on and wait for the next issue because it is such a large capital outlay for most.

IMO it is not possible for Tesla to survive without using smart marketing and development techniques.This is not about greed but rather about survival. What use would Tesla be if it went out of business because of poor business sense?

Brian H | 28 novembre 2012

Tiebreaker | November 28, 2012 new
Just that [XYZ]'s enthusiasm for technology is $$$$ driven. So is Tesla's.

As Elon has observed, as have many others, starting a new auto company is a really, really hard and low probability way to get rich. It is barely weeks past a near-death experience. It is prepared to license its tech and patents to anyone (non-exclusively), and wishes Toyota and MB would hurry up and replicate its approach.

In the big picture, I see nothing to substantiate your generalization.

Anyway, it irks me the insistence that TM is not using the battery just to sock us all, and not seeing any other reason.

I'm not sure what this says. Unintended double negative in there? Who is "not seeing"? The others? You?

As for Google, I avoid its services and trackers etc. as much as possible. That includes search engine, browser, and products, and I use Ghostery to block its trackers (like 'Google Analytics') wherever that doesn't disable a site I need/want to watch, etc. And NoScript similarly.

pvenkate | 28 novembre 2012

Question: Where can I find the exact verbiage for Tesla's battery warranty? In particular, I want to know up to how much battery degradation is covered? I have not seen any mention of that except 8 year/100K miles of normal use. I am also interested in the life expectancy of their battery pack past the 8 year warranty period.

Timo | 28 novembre 2012

@blackscraper, I think you are missing the point a bit.

Tesla whole product relies of it being the best into business, for that reason alone it would be stupid for them not to use advances into battery techs. They have to. They would die without that immediately after one of the big ones makes a serious effort in pure BEV section.

But they also have to offer their product to customers with cheap enough price tag, so as long as new battery costs them more to produce same quality product they will not use it. This is business, not charity, so making money is only way for it to work.

Volker.Berlin | 29 novembre 2012

Well, everybody holds his/her own belief. While I won't call you naive, I will call myself pessimistic [...] (blackscraper)

Fair enough. I guess I only really take issue with the way you stated your opinion as if it were fact. Seems to be a pet peeve of mine...

What I am worrying is, Tesla is not even looking into replace 18650A with 18650B or other more advanced products. (blackscraper)

Volker.Berlin | 29 novembre 2012

Where can I find the exact verbiage for Tesla's battery warranty? In particular, I want to know up to how much battery degradation is covered? I have not seen any mention of that except 8 year/100K miles of normal use. I am also interested in the life expectancy of their battery pack past the 8 year warranty period. (pvenkate)

That's in fact a very interesting question (that doesn't actually belong in this thread but warrants its own IMO). Up to now, Tesla has been careful not to offer any hard numbers. Their entire language in this regard is watteweich (what's that in English?), i.e., leaves a lot of room for interpretation. The intention is clear, but how a legitimate warranty issue is determined, is not (at least not to me).

There is this number of 70% nominal capacity that keeps popping up. Thus, if within 8 years your battery loses more than 30% of capacity, I'd expect that's definitely a warranty issue. It was also mentioned that in reality for an average battery pack, they expect twice the life time, i.e., no more than 30% capacity loss in 16 years. The truth is probably somewhere in between.

Vawlkus | 29 novembre 2012

I think the word you want is "vague".

I also think that it's deliberate because there are a plethora of factors to consider in regards to battery degradation. I mean if you drive to empty and recharge every day your battery will degrade faster than some else's if they're just driving 50 miles a day and topping up at night. Too many variables and not enough history to go by yet IMHO.

Volker.Berlin | 29 novembre 2012

Of course it's deliberately vague, and understandably so. At the same time I think it is similarly understandable that a "vague warranty" does little to appease the cautious customer.

Vawlkus | 29 novembre 2012

"Fortune favors the bold"....... up until their battery dies :D

johnchamplinhall1 | 29 novembre 2012

Some comments on this thread from and old lithium battery guy (and the holder Tesla reservation #3937). The Panasonic 18650b does not incorporate a lithium silicon electrode. It appears to be a better packaging job of the cells with perhaps some tweaks to the nickel based positive electrode. This cell has been under development for at least three years and presumably Panasonic and Tesla have been evaluating it. It sounds like an evolutionary rather than revolutionary product and Tesla could very likely implement it as part of a continuous product improvement program. By the way its specific energy is only 5% greater than the 3100 mAh so don’t expect a 750 km car.
Panasonic does have a 4000 mAh lithium silicon cell under development. This cell as announced in 2010 comes with a 3.4 vs. 3.6 average voltage and a 54g vs. 44g mass. The bottom line is that its energy density is 800 Wh/l vs. 620 Wh/l so use of this cell would potentially lead to a 110 kWh battery weighing 70 kg more.
While the potential for greater range is clearly tempting lithium silicon is not an evolutionary change. The life of the current Panasonic nickel based 18650 cell is almost certainly limited by the positive electrode. This may not be the case with lithium silicon. As a young man my first battery patent taught the first method for stabilizing the lithium silicon electrode. Much work has been carried out since but the status is very proprietary to the battery developers (Panasonic, Sony, etc) and OEM customers (Tesla).
Finally Panasonic isn’t the only game in town. Interested parties are directed to the Silicon Valley startup Evnia which has reported a 400 Wh/kg lithium ion cells with a 500 cycle life.

Brian H | 29 novembre 2012

"wetteweich" would be soft, fuzzy. Less polite: squishy, or mushy.

BTW, the 8yr. battery life at 8% improvement per year would improve it by >90%. Whether that incorporates any of the laboratory "breakthrough" techs is the really interesting question.

RDoc | 29 novembre 2012

8% per year for 8 years is 85% improvement (1.08 ^ 8 = 1.851) so for the same price an 85 kwh battery becomes 157 kwh, or an 85 kwh battery costs %54 of the current price.

nickjhowe | 29 novembre 2012

And/or TM's margins go up. Cost ≠ Price

Brian H | 29 novembre 2012

UR rite, of course. Roughly, it takes 9 yrs at 8% to double, by "the rule of 72"; rate x periods =~ 72 for 1 doubling. So 72/8 = 9. ;)

If the improvement rate improved to 12%, then it would only take 6 yrs: 72/12 = 6. And so on.