The official reason was to simplify the assembly lines by taking out one of the battery configurations. But there was another technical observation to share in the 2018 EVs: The three 75 kWh Teslas had ranges that were close to the Chevy Bolt but worse energy consumption, kWh/100 mi. Elimination of these three models further separates the Tesla vs everyone else with a wider performance gap. It doesn't hurt that the 100 kWh pack models have a higher profit and the Model S/X lines are going to two shifts. This also lets Tesla do some assembly line tuning. Bob Wilson
I don't believe the elimination of the Tesla MS/MX 75 kWh battery pack had anything to do with competition with the Bolt EV. The latter isn't even remotely in the same class as the Model S or Model X. I think the elimination of all but the largest MS/MX battery pack size was in preparation for more important changes to come with those models. At the very least, Tesla is going to offer a new, larger battery pack size. That's pretty obvious, and follows the clear pattern in the past when eliminating one battery pack size happened shortly before or after introducing a new larger size. But beyond that, my working hypothesis -- based on nothing but pure speculation, I admit -- is that Tesla is getting ready to switch the MS and/or the MX over to the cheaper 2170 cells made at Gigafactory 1. Furthermore, I speculate that this will be part of a major refresh for the MS and possibly also the MX. Tesla made a lot of cost-saving innovations in the Model 3, such as a shorter wiring harness, which it's going to want to introduce into the MS and MX sooner or later. Perhaps it's too soon for that to happen... and perhaps it's not. If I'm right about this, then we'll see a refreshed MS -- if not also a refreshed MX -- within a couple of months.
Makes sense, except that Elon said in the last analyst call that the S and X aren't moving to 2170 cells. Also, he recently stated that they don't do major refreshes, but rather improve cars on a weekly or so basis.
Yes, I noticed that. Not being an investor myself, I'm unsure what the rules are on what can or can't be said during investor conference calls. My hypothesis is that Elon said that only as part of an ongoing attempt to avoid the Osborne Effect; not tipping Tesla's hand regarding a major refresh. Tesla will want to announce that right before it happens, and not before. But of course, I could be wrong, and you offer some evidence that I might well be. Certainly my hypothesis violates Occam's Razor; it's not the simplest explanation that fits the facts that we have. The simplest explanation would indeed be that Tesla has indefinitely put off switching the MS/MX packs over to 2170 cells. But I don't believe it's reasonable to assume that will remain the case for years; I would guess it will happen sometime this year, even if it happens later than I'm suggesting. *Shrug* Perhaps that's just a difference in semantics. I would call the change in the Model S's front end, from the older "nosecone" style to the new one, a major refresh. Perhaps Elon would not. Certainly it's entirely possible that Tesla will switch the MS/MX battery packs over to using 2170 cells without other major changes at the same time. I'd think it would make more sense to do any major changes all at once, rather than in steps, but then I don't work at Tesla, so I could be wrong there.
I don't think there's a big enough improvement in energy density in the new cells to warrant the change. The Model 3 can take advantage of them because its pack is newly engineered and not structural like the ones in the S and X, so on the pack level it has great energy density. One the cell level, it's not that big (though it probably has advantages besides just a bit better energy density)
No, it's the difference in cost that will be the major motive for Tesla to make the switch. The cost per kWh is significantly cheaper for 2170 cells than for 18650 cells. I'm unsure that there is actually any improvement in energy density (ED) between Panasonic's current 18650 cells, and the new 2170 cells. I've seen very passionate arguments both ways on the Tesla Motors Club forum, and I certainly don't think I have an informed opinion on the issue. Tesla claimed a 30-35% improvement in ED for the 2170 cells, but I think that was mostly hype, and I think that was just a comparison to the ED of the 18650 cells Tesla was using when the Model S was designed... not a comparison to the ED of Panasonic's current 18650 cells. I'm surprised that Tesla has left that amount of money "on the table" for so long, and I suspect it's only because Panasonic hasn't ramped up cell production as fast as Tesla hoped they would. But Tesla's production more or less plateaued during Q4 2018, so Panasonic got somewhat of a breather; perhaps enough to start producing enough cells for the MS/MX packs too? Or perhaps not. It's a pretty well established fact that that 2170 cells are cheaper (per kWh) than 18650 cells, but otherwise this is all just speculation.
At nearly two hours, Jack Rickard is somewhat loquacious (i.e., never ask him where the bathroom is if you've really got to go!) Regardless, he does a fairly deep dive into the technology and I've wasted more time on other things than watching: 46:03 - where he goes into the specs and economics Bob Wilson
