Gauss Guzzler
Safety Score = 42
Does it continue charging during the reboot? Otherwise you’d lose a few minutes of charge time and defeat the whole purpose, damaging your battery for nothing.
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Did you know the 3 heats the battery (actively) constantly while DC charging at any speed or temp?
- Thread starter FalconFour
- Start date
Charge continues during reboot. However in my US car charging on CCS (adapter) the heating does not stop.
Does your Model 3 have a heat pump? I assume you used Scan My Tesla to verify neither the heat pump or stator motor windings were not actively heating the traction battery?
Regards
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Model Y 2022 AWD LR, with heat pump. I have not installed OBD yet (on order, arriving Friday). The way I checked for heater was rather "unscientific". From my ~50 DCFC at supercharger and 3rd party, I noticed when my car is actively heating the pack while charging, there will be a discrepancy between the number shown in app (also on the dispenser screen), and the number shown on the car screen.
The reason I say "heating does not stop" is because on the app/charger it says, i.e. 30kw, on the car it shows 26-28kw, before and after reboot. On a sufficiently heated pack, or AC charging under typical ambient temperature, this discrepancy is close to 0.
I will update with more data and test once I get the OBD installed. Hope you don't find my wild guesses offensive.
Latest update: got OBD and SMT installed. On a 40C battery plugging into CCS/100A public charger, “Target bat active heat” will go to 55C for a few minutes then drop down to 44C. However at that time none of the Cell Temp reached 55C. Therefore “active heating battery to ‘very high temps’ and disregarding what kind of DC input you have” is disproven.
Disclaimer: my findings are limited and preliminary. Will update when I have more chance to test.
@FalconFour This release notes make it look like it is possible that Tesla is finally resolving this issue. It would be interesting to know more details.
Maybe once it is out Bjorn can re-do his test on the ~22kW DC fast charger that showed the ridiculous heating. (That doesn't happen on 22 kW AC charging.)
Maybe once it is out Bjorn can re-do his test on the ~22kW DC fast charger that showed the ridiculous heating. (That doesn't happen on 22 kW AC charging.)
Oh my god, YES! That sounds like incredible news - the update we've only been waiting ~4 years to hear 
(Just in time for me to be interested in selling the Tesla after getting past the breaking point of such issues piling up...)
Of course, it'll be about another 3 months before it'll trickle down to those of us running FSD Beta, with the car software feature disparity... so I may never end up being able to see it. But hey... nice that it's _finally_ getting resolved. It very much sounds like that's the case, at least.
(Just in time for me to be interested in selling the Tesla after getting past the breaking point of such issues piling up...)Of course, it'll be about another 3 months before it'll trickle down to those of us running FSD Beta, with the car software feature disparity... so I may never end up being able to see it. But hey... nice that it's _finally_ getting resolved. It very much sounds like that's the case, at least.
Yeah, hopefully it is smarter about when it starts actively heating the battery on-route to to a Supercharger and also optimizes any heating based on the speed of the charger at a minimum. There's a ton of variables that they could also take into account to truly optimize this.
Not only does this improve the user experience for Tesla owners, but by reducing charging times that increases the effective capacity of Superchargers, too.
Heh--egg on the face of all the people here who vehemently denied it was a mistake or oversight and insisted that the Tesla engineers obviously knew what they were doing and had it set up that way on purpose.
Jeremy3292
Active Member
Can anyone provide a short and sweet summary of what we think is now occurring? Long thread here
I can test this when I get the update. I have a 125amp chademo that I'd love to have the 7kW back on
That or driving over to an urban supercharger (should see a clear difference) vs a v3 supercharger (should see no difference) and monitoring* logging how pre-heat and while-charging battery heating behaves with 2022.40.x - will be telling too.
Based on the vague release notes, it sounds to me like they are finally fixing this and mascarading it as a pure improvement vs a logic fix. Figures.
Based on the vague release notes, it sounds to me like they are finally fixing this and mascarading it as a pure improvement vs a logic fix. Figures.
- It was discovered (for me, shortly after the CHAdeMO adapter became compatible with the 3) that Tesla software has dumb logic for battery heating: "if the charging mode is DC, heat the battery" - target varies by battery type/chemistry but the logic is the same. End result: you waste 10-20% of charging energy on heating the battery, just to cool it right back off when DC charging is stopped (target moves back to 86f or so, and radiator dumps battery heat on the road). More waste for dual-motor cars, which heats the battery faster by consuming more of the charging energy (which is often station-limited). About 4kW for single motor, 8kW for dual motor - observed by a discrepancy between the station saying "50kW" for example, and the car saying "42kW".
- Mix of primarily "Nuh uhh you're stupid, Tesla engineers are infallible gods, lithium plating brooo" and "yeah, this is somewhat sub-optimal" responses
- ... years go by ...
- Tesla: "Hey, we're improving charging efficiency by being smarter about thermal controls based on what the station can actually deliver."
Meanwhile, I'm just over here dreading that it'll be another 3 months before I'll see it with FSD Beta. Probably.
Jeremy3292
Active Member
Interesting. Do we expect this change to be applicable only to third party DC chargers or SuC as well? Not sure how your Tesla would know you're going to a third party DC charging station...your only option is to put in a nearby SuC to preheat the battery currently.
I also wonder if this is applicable to SuC, if there is any material time savings to be had from this new logic.
not much savings when the (super)charger can put out out a lot of power as you'll get faster speeds from a hot battery. The main issue is the battery getting heated for no reason when it would be able to take the max power the charger can put out for most of the charge curve anyway.
7 pages....Long.... Thread?? Are you new here? We have threads with over 1,000 pages, would you like some links?
Hey, maybe we're one step closer to getting our USB Album Art restored, that Tesla removed back in 2020! (I'm back on the old firmware so my album art is loading.)
I loved the comments years ago when senior forum members were saying Just...Give...Me...Control...Of...The...Damn...Battery...Heater!!!
Actually, that came back with the 2021 holiday update -- just before V11 UI took our dreams of a coherent, bug-free user interface and shattered them on the floor. (hey, auto high beams will be usable soon, right? ... right?)
I was super excited to see USB album art back again. And then it started jumping over to Tidal every time the car slept/woke, and I started to forget switching to USB media, and then Dashcam stopped working completely in 2022.12, and I formatted the USB drive (and nuked the audio) to work-around that, and... I forgot to go back to USB media now that dashcam is fixed in 2022.20. Yay.
(sigh, death by a thousand papercuts)
It's not really about preconditioning (never was) - but rather, the behavior _while_ charging. While charging, if it's a DC charger, it would heat, regardless of whether it'd help. On Superchargers, it could have a little effect on 72kW urban SCs, but otherwise not really. It'll really help people (like me) that use a lot of non-Tesla DC charging...
Jeremy3292
Active Member
Was more interested in thoughts on the new software update, which @FalconFour answered for me kindly
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I come here more often to learn, than to share my silly opinions. Many people love to hear themselves talk, but I'm not one of those But when I do discover useful information about my Tesla, that's when I post.
But when I do discover useful information about my Tesla, that's when I post.Similar threads
