Are BEVs Taking Risks to Show Longer Range?

Tesla mortgages?

After you repay the loan - your car's range goes back up ... another business opportunity? ha
Their web configure / features page shows the prices just went up. $6,500 to upgrade to the full use/ 75kWh's. Makes sense. Other prices look like they jumped a couple thousand too. Snooze you loose.

battery capacity-buffer learning curve; often we think of heat generated most significantly at the top end. But deep/regular discharging takes its toll as well. The early Honda hybrid traction pack failures come to mind.
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Adding to what @Zythryn said on the topic, Tesla did this at the Model S's introduction for the few people that had ordered the 40kWh model. A software limited 60kWh pack was cheaper when factoring the costs of making the 40kWh for so few people. A big cost was that a different physical sized pack cost required separate EPA fuel efficiency testing. Telsa likely thinks this new Model S60's sales will similarly be small enough that paying those costs wouldn't be productive.

 

i'd guess crash testing different weighted packs would be a pretty penny too

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what's the cost difference in pack size to tesla?

 

It's speculative - but with gm's $150/kWh price for their volt, one can do a rough number crunch as a high for tesla. The gigafactory means no middleman, & no destination/ shipping.
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even at a hundred bucks, you're talking $1,500. per car?

 

At $100 per kWh $1,500 would only get you a 10kWh pack .... & it'd maybe need a 1kwh buffer at empty & 1kWh at full charge. The remaining 8kWh usable portion might get you 24-25 miles down the road. ymmv. Many folks would want to spend another $7K to $10K to diminish their concerns about range anxiety.
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sorry, i was talking about the difference between the tesla 60 and 75 kWh, if they made separate packs.

 

Interesting angle! In addition we not only have the falling cost difference - other good battery dynamics are coming to market as well. Lighter chemistries ... more energy dense / robust chemistries that get impacted less & less by heat & deep cycling. All that - & being 'made in the USA'.

actually, even as battery chemistries continue to improve Tesla is experiencing its ½ decade anniversary. So, with ONLY so few years to rack up miles here's some good degradation news from a company that's notorious for putting on the miles;
At 200,000 Miles, This Tesla Model S Experienced Only 6% Battery Degradation
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Tesla charges $10k over the S75D for the S90D*. The Gigafactory's goal is to get battery costs under $200/kWh. That implies the current cost for 15kWh is at least $3000, but likely more. Which might not include the structure(casing, cooling, etc) cost for the assembled pack. Tesla's cost for R&D and regulatory testing can be assigned to a portion of the price they charged.

Before writing that out, I should have looked at the S60 to S75 price; it's $6500. An actual 60kWh pack would be priced $3500 more then. Which is probably a fair guess at how Tesla charges for that R&D and regulatory stuff.

*On introduction, wasn't the price difference between pack sizes $20k?

As to the OP, a short sighted company could overstress their batteries for better figures. I don't see public and regulation demand for plug ins going away, and if doing so results in quickly lossed capacity or dead packs, that car company's name will be mud for plug ins, and they'll lose customers. See Honda and hybrids.

 

It actually is not in total contradiction to what we know about batteries.
I did not say there was NO degradation, just none the drivers noticed, which is very consistent with battery research.
When you don't allow a battery to reach the top or bottom 16% SOC and it has active cooling, the degradation is very very slow.
I expect you could eventually see degradation at some point, but most Volt batteries will likely last the life of the vehicle.

GM was overly conservative with the battery packs. Using a little more now that they have hundreds of millions of electric miles under their belts, should not be an issue.

 

Yep - & tesla - as of last April has driven over 2 billion miles ... although a handfull of cars have had questionable modules replaced (detected via ota monitoring - not even known to the driver) - the 8yr/infinite pack-motor warranty hasn't been a financial liability to the company. With still more improvements to come.

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One of the things I admire about the Tesla architecture are the parallel-series strings. There are going to be a non-zero number of defective cells and the Tesla system assumes they will happen ... and in effect bypasses them. This allows the car to continue its journey instead of being towed to the shop. At first it looks a little complex until you realize what it does for reliability. However, without a range extender engine of some type, not my style.

Bob Wilson

 

Amen to that. After 40+ miles of detours last night, the ICE had to come on to get me that last mile home.

 

Still ... think about it - how far they've come. In a measly ½decade we've gone from mass produced ev's & phev's with 70ish miles & 30ish miles respectively - to 300ish miles & 50ish miles respectively. Charge infrastructure continues to move forward as well. Would it be too far-fetched to presume 315 EV miles will be the ubiquitous minimum in the next ½-decade? Who knows - pouring engine blocks may diminish more quickly that folks can fathom.

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It's still not know for certain just how much of the Bolt EV battery is used but here is the recently release warranty info (8yr/100k) on it:

"Like all batteries, the amount of energy that the high voltage “propulsion” battery can store will decrease with time and miles driven. Depending on use, the battery may degrade as little as 10% to as much as 40% of capacity over the warranty period. If there are questions pertaining to battery capacity, a dealer service technician could determine if the vehicle is within parameters."

Page 322: https://my.chevrolet.com/content/dam/gmownercenter/gmna/dynamic/manuals/2017/Chevrolet/BOLT%20EV/Owner's%20Manual.pdf

 

Yikes! ... that'd mean for example - 1½yrs after purchase, as long as your car still travels ~ 135 miles of its original 238 range you're still not able to make a warranty claim, because you may have suffered only a 39% capacity loss. Doesn't sound like gm's trying to create much confidence in their product.

Tesla opened up their patents - kinda makes one wonder why gm didn't read up & do some reverse engineering.
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40% over 8/100 would be very disappointing. it's kind of a disclaimer, and probably would require extreme conditions. but still. does the volt have similar?

 

Keep in mind that GM is tied to their dealer network.