110 V charging harm?

[Sj-trekhaak]

During charging the computers in the car keep running. Because the memory in the computer has an finite lifespan, the longer the computers are online the sooner the memory gets to the end of its life.

So the faster you charge, the sooner the computers can go to sleep.

More info: Preventive eMMC replacement on MCU1

 

[user212_nr]

During charging the computers in the car keep running. Because the memory in the computer has an finite lifespan, the longer the computers are online the sooner the memory gets to the end of its life.

So the faster you charge, the sooner the computers can go to sleep.

More info: Preventive eMMC replacement on MCU1

In computer programming, we have a saying about "the evils of micro-optimization". People (ie. skilled programmers) think that computers have a "hard time" doing all the little things we ask them to do, but this is not the case. They do billions of operations per second and when you add five thousand more the effect is not measurable. The effect of "wasting time thinking about it and being proactive" about those few operations can cost thousands of dollars.

 

[vickh]

https://electrek.co/2017/05/07/tesla-limits-supercharging-speed-number-charges/

During charging the computers in the car keep running. Because the memory in the computer has an finite lifespan, the longer the computers are online the sooner the memory gets to the end of its life.

So the faster you charge, the sooner the computers can go to sleep.

More info: Preventive eMMC replacement on MCU1

that's seems counter to the plugged in Tesla is a happy tesla hypothesis? Maybe a MCU1 problem that's been resolved in the current HW?

 

[Rocky_H]

that's seems counter to the plugged in Tesla is a happy tesla hypothesis? Maybe a MCU1 problem that's been resolved in the current HW?

Being plugged in does not = actively charging.

 

[vickh]

Being plugged in does not = actively charging.

hmm the car doesn't wake up and top off ?

 

[user212_nr]

hmm the car doesn't wake up and top off ?

The individual in the linked thread is aware that SSD hard drives have limited write capacity. Approx. 1 million writes per sector (ie. the drive can be overwritten "only" 1 million times). He's got 5 years, 240 km, so he thinks (keyword thinks) his time has come, and wants to "pre-emptively" de-solder the eMMC chip and copy its contents to a new one. This will save him 3000 EUR of replacing the mcu IF it fails due to that chip.

I suppose if I were at 150k miles, that might sound reasonable. At that many miles 3k is a resonable repair, I think.

Very good thread, actually, but I wouldn't worry people about it.

 

[Rocky_H]

hmm the car doesn't wake up and top off ?

Not constantly. That is the point, that the car can sleep in a low power hibernating mode for many hours. If you have the scheduled charging turned on, that can be almost 24 hours until it hits the next scheduled time. And even if you don't have scheduled charging turned on, it does not keep all of the connections live with 240V in that whole cable running a trickle charge all the time. It will finish a charging cycle, and then shut off and go to sleep for many hours. It lets the battery go down by about 3% below your set target before it will pull itself back awake to run another charging cycle to top that off again and then go back to sleep.

 

[Rocky_H]

The individual in the linked thread is aware that SSD hard drives have limited write capacity. Approx. 1 million writes per sector (ie. the drive can be overwritten "only" 1 million times). He's got 5 years, 240 km, so he thinks (keyword thinks) his time has come, and wants to "pre-emptively" de-solder the eMMC chip and copy its contents to a new one. This will save him 3000 EUR of replacing the mcu IF it fails due to that chip.

That is taking a concept that is accurate, but having too simplistic a view of it. This person is assuming the exact same place in the flash memory is getting written on over and over and over, and so they have to swoop in like Superman to save the day and rescue it from those memory areas getting worn out and destroyed.

It doesn't account for the industry practice of "write leveling". Write leveling itself means spreading the writing of information around to different sectors in the drive, so you're not hammering on the same place all the time, killing that area faster. But beyond that, have you ever seen this happen with a USB flash drive that you have had and used for a long time? It starts out, and let's say it's a "32 GB" drive. When you plug it into the computer, of course it's binary size, so it says something like 29.3 or whatever. As you use it for a year or two or three, you may start to notice that it doesn't still say 29.3 anymore. It will start to show 29.1 and then 28.9 and then 28.5, etc. etc. The capacity continues to drift down and shrink a little bit. That is because there is internal circuitry in that USB drive that counts and keeps a log of each location and how many times it has been written to. If sectors get written too much and start failing, those get pulled out of the addressable area and marked for do not use ever again. That is why the displayed capacity gets reduced.

So these flash chips take care of preserving their own lives through these methods, and as long as there is some excess space not used, they can continue to "heal" themselves by using that spare area to move things around.

 

[geowhjr]

https://electrek.co/2017/05/07/tesla-limits-supercharging-speed-number-charges/

What I'm getting from that article is that 300 superchargers would initiate slower charging? ;

"245 total charge ups on CHAdeMO only – and he estimates that he used Superchargers on “50 to 60 occasions” on top of that"

And it also appears CHAdeMo is considered supercharging ?

 

[Rocky_H]

And it also appears CHAdeMo is considered supercharging ?

Yes, they count all brands of DC fast charging in this. The very first person who discovered this had barely used Supercharging at all, but had been using CHAdeMO a ton.

 

[doghousePVD]

Canada has a lot of 30 kw ChaDeMo. I wonder if the counter considers it the same as 150-250 kw SuperChargers, or considers the faster speed more strenuous.

 

[vickh]

Canada has a lot of 30 kw ChaDeMo. I wonder if the counter considers it the same as 150-250 kw SuperChargers, or considers the faster speed more strenuous.

But don't Tesla's SC have built battery protection mechanisms? Does frequency of charging matter more or speed/ temp?

OT for the 1st time in months The car said it was preconditioning while I was driving to a SC. Is it helpful for longevity to put it into the nav vs an unplanned top off? How about for destination chargers?

 

[Rocky_H]

Canada has a lot of 30 kw ChaDeMo. I wonder if the counter considers it the same as 150-250 kw SuperChargers, or considers the faster speed more strenuous.

Yes, the counter counts it no matter what as long as it is DC charging, regardless of any power threshold. But for sure people brought that up in the huge throttling thread, that it seems a bit hokey to have to count it when it's rather weaksauce 30-40kW.