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[DonTom]

“The cars currently built are all designed for a million miles of operation. The drive unit is design, tested, and validated for 1 million miles of operation.”

Click here.


-Don- Reno, NV

[Richard230]

How in the World do you test a battery to prove that it will last a million miles, without actually driving a vehicle that far?  That reminds me of Zero claiming in their 2017 paper brochure that their battery in the S with PT will last for 455,000 miles.  I kind of doubt that any Zero has ever gone anywhere near that distance.  And forget the battery pack, will the chassis components and motor last that long?   

[Crissa]

There are testing algorithms to speed up weathering and degradation.  Charging and discharging the battery pack for n number of cycles and counting the number that die and how much damage, then applying a mathematical theorem to produce an expected failure curve.

This is standard in industrial processes.

Has anyone driven that?  Well, since they have automated systems or just putting the car up on rollers or plugging a battery into a charge/discharge cycle tester they can simulate many use cycles or miles much faster than just by 'driving'.

Heck, Waymo says among their few hundred vehicles 10 million miles, for instance.  And that's just on the road.  Waymo has been driving on the road for about as long as Tesla's model S has.

-Crissa

[DonTom]

How in the World do you test a battery to prove that it will last a million miles, without actually driving a vehicle that far?  That reminds me of Zero claiming in their 2017 paper brochure that their battery in the S with PT will last for 455,000 miles.  I kind of doubt that any Zero has ever gone anywhere near that distance.  And forget the battery pack, will the chassis components and motor last that long?   

For now, we have to consider it a vaporware battery.

-Don-  Auburn, CA

[Richard230]

How in the World do you test a battery to prove that it will last a million miles, without actually driving a vehicle that far?  That reminds me of Zero claiming in their 2017 paper brochure that their battery in the S with PT will last for 455,000 miles.  I kind of doubt that any Zero has ever gone anywhere near that distance.  And forget the battery pack, will the chassis components and motor last that long?   

For now, we have to consider it a vaporware battery.

-Don-  Auburn, CA

Sounds familiar.   

[NEW2elec]

Well I think it's just a bit of cheeky math.
The old Zero miles for life of the battery stats were just based on a 2500 charge cycles times the city range for the bikes.
So 200 miles range times 2500 is 500000 miles.
If Tesla is making a battery with 400 miles of range, maybe a 150 kWh pack and multiply that by most Li ion cells cycle life of 2500 cycles then boom you get 1 million miles.
In theory of course. 

[Crissa]

Yep.  It's just math. 

[Doug S]

Yeah, I'm sure it's based on charge cycles. Put a 1C load on it, then charge it at 1C. Takes maybe 3 hours for a full cycle, so you can do 8 cycles per day. It doesn't take all that long to verify 2500 cycles.