Two Reasons It's a Bad Idea for GM to use Tesla Superchargers
The Chevy Bolt is a smaller car with presumably a smaller battery. Pumping that current is not a good idea; Tesla gets away with because of battery size. Sure the Bolt could be designed to throttle back the charge, but then you lose some advantage to the quick charge.
Second issue is battery chemistry. Not all lithium batteries are created equal and they. Tesla uses NCA. The Bolt, if the whispers are to be believed, is supposed to use NCM.
From what I've read NCM degrades faster than NCA.
Essentially you have a shorter longevity with NCM and further shortening the longevity by charging it at a higher rate. Will it make a difference in terms of battery longevity, it depends on various factors, but enough of a risk that I wouldn't risk charging at that rate with that chemistry.
The Teslas all have the same battery chemistry. The 60 and the 85 have less risk, since the battery packs are larger; packs lower than that you have to taper back to get the appropriate C so you don't cause as much damage. There are conflicting statements from Tesla, but if you look at Charge rate vs degradation, the faster you charge the faster you degrade the batteries;
When you do that, you will not get the benefits of supercharging and may as well use other standards like CCS or chademo- get no benefit from the SC.
From the degradation curves it appears the number of cycles for NMC to reach 70% capacity is 20% less than that of NCA.
So that's a problem; same reason why Tesla does not retrofit the roadsters to supercharge- the BMS can handle it, but the chemistry inside can not- supercharge LCO a handful of times you'll start seeing degradation.
There's only 2 chemistries that should be recommended for fast charging NCA and lithium titanate; anything else you start getting shaky to some degree.
NCA is not perfect either, but it's one of those that can be solved by engineering and battery management controls at a cost to efficiency.
- If I was to design a pack without any weight concerns, and has fast charging, lithium titanate hands down
- If I wanted low weight without any regard to quick charging or degradation- LCO
- If I wanted quick charging and low degradation (no where near titanate's benchmark though)- NCA
- If I wanted medium degradation, low cost, moderate charge rates-NCM
If you wanted lowest cost, stable, medium weight, medium/high degradation, no fast charging- LMO or iron phosphates.