An Idea for fixed battery replacement cost - Tesla please read this

[MitchJi]

I reality, I can appreciate the costing side of things might not be quite so straight forward but I can guarantee this will convince a lot of the remaining EV skeptics that a Tesla EV is indeed a very good choice whether buying new or used - this will be vital if Tesla wants to be in the list of top sellers overall, not just EV.

You know that Tesla has 373k reservations for the M3?

By the time your M3 needs a new battery, new battery packs will be so cheap (probably under $50 per kWh) that all you need is a commitment that Tesla won't try to screw you on the price. Even if they do used battery packs from junk yards will be a very viable option.

 

[int32_t]

I hope they will be able to replace some of the batteries in the pack if they go bad before others.

My Insight battery pack had to be completely replaced after *one* cell went below tolerance, which seemed excessive.

I'm sure they did just that. They charged you a bunch to replace the whole pack, took the old one back and some technician took it apart, located the bad cell, and replaced it. Now it's a refurb pack cruising the roads in another Insight ... I'm sure it's doable yourself as long as you are willing to take a few risks and don't mind voiding any remaining warranty.

Cells that bad sure aren't common ... how many vehicles has Tesla produced? 100k? And how many cells are in each one?! Still haven't heard of any packs being replaced due to actual battery issues.

To sum up: still not the slightest bit concerned about (Tesla's) battery longevity.

 

[Jayc]

You know that Tesla has 373k reservations for the M3?

Yes and 373k will be about 0.5% of global annual car sales

 

[Booga]

I wonder if one of the future uses of the powerwall is to sell cheaper units (maybe utility grade or something) that have used cells from tesla cars. If so, then that increases the value of these later on. Maybe the model 3's pack will be designed in a way that it's more plug and play for this option 10 years into the cars life and not require lots of manual labor.

 

[Laban]

No, there have not.

After 2 1/2 years and 44K miles, my S85 charges to 256 Ideal Miles. When new it charged to 265. That is about a 3% capacity loss. It is an established fact that on average, the highest percentage annual loss is in the initial year and after that the loss is typically 1% or less per year (see the Plugin America study). That's trivial. After a decade, a Tesla will still have a very usable battery.

Just to clarify what the 3% initial, 1%/year loss actually means:

10 years: 88.77%
20 years: 80.36%
30 years: 72.75%

Actual data - 95 000km/1.64 ~= 58 000 miles:

 

[wdolson]

I wonder if one of the future uses of the powerwall is to sell cheaper units (maybe utility grade or something) that have used cells from tesla cars. If so, then that increases the value of these later on. Maybe the model 3's pack will be designed in a way that it's more plug and play for this option 10 years into the cars life and not require lots of manual labor.

Why do you think the current packs would take extra labor to repurpose? The 85/90 pack now is made up of 16X modules of 444 cells each. A stationary storage setup can (and has been) be made from a few modules taken from one of these packs. wk057 took apart some battery packs from wrecks he bought to use in his home solar system. Some others may have done the same and we haven't heard about it.

I just looked up the capacity of the power wall and it's 6.4 KWh, which is a weird number until you multiply it by 16. You get 102.4 KWh. If you multiply by 12, you get 76.8 KWh. The recent bump to 75 KWh batteries in the lower end S and X is probably using the new battery chemistry coming for the 100 and what they are using for the Powerwall.

It makes perfect sense to use the same modules for everything and just scale as needed.

As used batteries become available in quantity there probably will be some form of Powerwall with used batteries, whether from Tesla or someone else. With batteries in EVs lasting a lot longer than anyone expected, especially Teslas, it's going to be a while before these sorts of batteries are available in any quantity.

 

[eisbock]

Once upon a time long ago, I heard that lithium batteries "plateau" after a while, roughly around 70%. Is this still true? Am I thinking of another battery?

This means that you will have constant degredation to 70% or so, but then you'll have much slower degredation after that. If that's the case, 60-70% for the same number of years that it took to get to 70% should be more than adequate and will surpass the lifespans of modern ICE cars, while still providing reasonable range.

 

[Booga]

Why do you think the current packs would take extra labor to repurpose?

I actually had no clue, so thanks for the detailed response (I cut it out of the quote just for the sake of screen space).

 

[MitchJi]

I just looked up the capacity of the power wall and it's 6.4 KWh, which is a weird number until you multiply it by 16. You get 102.4 KWh. If you multiply by 12, you get 76.8 KWh. The recent bump to 75 KWh batteries in the lower end S and X is probably using the new battery chemistry coming for the 100 and what they are using for the Powerwall.

It makes perfect sense to use the same modules for everything and just scale as needed.

That's not what Tesla is doing. They are using an different chemistry for cars, which is optimized for energy density. The e TE chemistries are optimized for higher cycle rates with deeper discharges.

 

[MitchJi]

Once upon a time long ago, I heard that lithium batteries "plateau" after a while, roughly around 70%. Is this still true? Am I thinking of another battery.

Depends on the specific type of lithium battery. You question is like asking:
I heard that gas powered cars get 25 mpg. Is this still true....?

 

[eisbock]

Depends on the specific type of lithium battery. You question is like asking:
I heard that gas powered cars get 25 mpg. Is this still true....?

Oh, I'm sorry. I meant the type of lithium battery that Tesla is not using.

Because that seems to be the most relevant type of lithium battery in this discussion.

 

[lklundin]

I would have to disagree about modern ICE cars being long-lived and trouble free. Yes you can get 100k from any manufacture, but going to 200k in anything that isn't a toyota or honda requires a fair amount of maintenance including timing belts/ chains, valve adjustments, alternators, water pumps, cooling systems, catalytic convertors and exhaust systems. No way 200k from any performance / luxury brand (maybe lexus) is going to be without at least $5k maintenance on the drivetrain. God help you if serious engine or transmission occurs above 100k miles. .

From anectodal evidence I also have to disagree. My current Audi has 285k and it's doing fine, top speed is down from 275 km/h to 272 km/h, nothing but scheduled maintenance so far. I hope I can keep it running until I get my Tesla, and then keep it as a back-up (I prefer the option to be able to drive 1200km in one day, or 800km in a day towing a trailer(*)). The last I heard, the two Audi's I previously owned are also still driving, each also at 200k+.

But it is true that a well-built BEV should have a significantly longer life than a ICE. It was a pretty big deal around here when the first owner of a VW Golf passed 1 million km (in about 20 years, I think). I would expect that not to be uncommon for BEVs.

(*): When will Tesla Motors offer a tow hitch for the Model S? What if I just need to tow something to the other side of town every once in a while? With its power and weight that should be no issue at all...

 

[wdolson]

Someone makes a trailer hitch for the Model S which looks almost identical to the Model X hitch. Check out the videos by kmanauto, he has one and has towed trailers with both his Ss.