Wiki Sudden Loss Of Range With 2019.16.x Software

[liamharry]

Early indications seem to imply that this new firmware has no ability to detect that previously capped cars are actually-ok and restore them back to normal. However, the new firmware does appear to be able to determine that some of the capped cars were more critically damaged than was previously estimated and those cars are being flagged with a failing battery message and being told to bring the car in for a battery swap:
Maximum battery charge level reduced

I note from the ‘failed HVBP’ thread that so far it looks around six cars have had this message come up with the suggestion they are all on 2019.40.2.3

Also suggests that they have done around 6-7 charges on the new FW before the message appears.

I’ve done my first 20% - 90% charge and wonder if it is now Russian roulette as to whether this message appears in 5-6 charge ?

Of course the flip side of the coin which would be interesting to know, is there any on here that have completed several charges on the latest firmware, who haven’t had the message and no other change in their range/charge profile?

 

[Ferrycraigs]

I could see the logic in BMS not bothering to balance until the pack is closer to full--why bother balancing at, say, 50% SoC. If balancing is a final step at higher SOC, I can see that unplugging early would short circuit that (forgive the pun)

From the very few occasions where I sat and watched, I saw BMS beginning to start balancing as soon as it started charging. ie the spread (imbalance) never got worse, only ever better. So what is the downside of stopping a charge part way through? I would have thought the balancing process would be appropriate for the SoC at any given moment. I say that as I have never seen any attempt by BMS to fully balance by, say, 80% if 80% had been selected as the charge level. If I have that wrong and it does indeed try to fully balance by the time the Charge Limit was reached, I could see that stopping it early might interrupt that balancing process, but even then I’m failing to work out how that might damage the battery. Is it not correct to say that all batteries are unbalanced, to some extent, throughout their operating life.

 

[liamharry]

It certainly did not help me - 40.2 knocked my theoretical* 100% from ~220 to ~205 rated miles.

Ahh, OK - think answered my question in part.

 

[DJRas]

Surprisingly again I had over 100kW charging today for minutes.
The cell temps were about 100F.
Display provided by Teslalogger
I arrived at the SuC with 2 miles left

 

[Battpower]

Modern BMS will shuttle charge from higher cells to lower instead of just bleeding off through resistors. Apparently they can do this throughout the SOC range instead of waiting for a higher SOC to be reached.

I doubt we can be privy to all the data we would need to fully know what's going on. Scatter graphs like those being built up by ABRP but for battery cell voltages etc would show interesting patterns.

Did I read here that newer packs do the charge shuttling but not older ones? I certainly understood for some non-tesla ev's that the very slow final 5% charge was due to cell balancing phase, but such an algorithm would presumably require charging to 100% to balance the pack.

So Tesla's recommendation to try and supercharge in a mid band range of SOC's would suggest cells do balance in that range, at least for newer tech.

But I also noted Elon apparently encouraging home charging when possible which smacked of lower charge rates giving pack more chance to cell balance.

 

[Droschke]

It certainly did not help me - 40.2 knocked my theoretical* 100% from ~220 to ~205 rated miles.

That might be considered "sudden and significant loss of range", don't you think?

 

[Battpower]

Is it not correct to say that all batteries are unbalanced, to some extent, throughout their operating life.

I would certainly agree that this would need to be the assumption of the BMS so that whatever state of imbalance it found, it would try and improve / reduce imbalance.

And if this is at least the case with newer cars, then it would support the view that repeated interruption could be problematic while occasional interruption should not cause a problem.

If some batteries have less sophisticated charge shuttling then they may be subject to an increased risk of ever increasing cell imbalance.

 

[Gixx1300R]

 

[David99]

This balancing discussion where everyone is coming up with their own theories is rather pointless.

My pack has excellent balance and I stop charging early almost every time. I use superchargers almost exclusively right now giving the battery very little time. Yet my pack is balanced just fine. It always has been and I have had vastly different charge and driving habits over the last 6 years. It never changed. Can we please stop coming up with random theories about balancing that's would favor one or the other battery treatment. The car is perfectly capable of balancing the pack in *any* condition and use case. Tesla sure upgraded the hardware and software over the years but as we can see even the oldest cars can keep a pack very well balanced after many years and well over 260k miles.

I'm so annoyed by it because Tesla told me this nonsense about balancing and how I need to follow a certain procedure for 6 months to balance my pack. It's all hogwash and distraction from this problem discussed here.

A pack that is *grossly* out of balance did not get there because the owner stopped charging or any other patterns. It's because some cells went bad for some other reason. It is not the systems limitations that caused it. Something is wrong with those cells. But again, cell balance isn't the issed for this software induced battery capping.

 

[Battpower]

Comes as no surprise. I would love to see a list of cited evidence of 'new' battery technology including BMS etc. and if there is any material difference from earlier configurations. This whole thread seems to be trying to identify if there are finite and individual failures that Tesla appears to be mishandling vs a much broader problem that Tesla is trying to address.

Not directly related, but when evaluating home energy systems 4 or 5 years ago, if you dug deep into Tesla's wty terms you would find that Tesla had a hard limit of the amount of energy passing through the powerwall. Not charge related, but none-the-less a hard performance limit that Tesla linked to warranty, presumably to limit their exposure to claims.

 

[omarsultan]

That might be considered "sudden and significant loss of range", don't you think?

I dunno, range kinda feels like this right now...

I am waiting to hit bottom. The drop after 40.2 is less than the drop after 16.x, so dropping less fast is kinda like improvement, right?

 

[Newscutter]

Could be completely unrelated... But if it isn't... There's a huge fire in Norway at the Stavanger airport that officials say was caused by a parked EV.

 

[omarsultan]

Comes as no surprise. I would love to see a list of cited evidence of 'new' battery technology including BMS etc. and if there is any material difference from earlier configurations. This whole thread seems to be trying to identify if there are finite and individual failures that Tesla appears to be mishandling vs a much broader problem that Tesla is trying to address.

Not directly related, but when evaluating home energy systems 4 or 5 years ago, if you dug deep into Tesla's wty terms you would find that Tesla had a hard limit of the amount of energy passing through the powerwall. Not charge related, but none-the-less a hard performance limit that Tesla linked to warranty, presumably to limit their exposure to claims.

I kinda wonder how many of these cool features have secret, undisclosed timers on them. We have seen it with DCFC and Ludicrous/WOT launches. I wonder if the folks using 250kW charging or that just bought the acceleration boost are in for a nasty surprise down the road.

 

[Droschke]

I dunno, range kinda feels like this right now...

View attachment 497653

I am waiting to hit bottom. The drop after 40.2 is less than the drop after 16.x, so dropping less fast is kinda like improvement, right?

Yup, as long as you don't notice it. If you have not seen it, it must not be there. Some even take it further and say even if you're' seeing it, it's still not there

 

[Droschke]

Could be completely unrelated... But if it isn't... There's a huge fire in Norway at the Stavanger airport that officials say was caused by a parked EV.

It's very relevant, actually. Thanks.

Raging fire shuts airport in Stavanger

 

[David99]

Great video and important info. The 100 packs are no different than the previous ones and get limited as well. Two things: Tesla might say now that's the only limit they will apply but we know that's very unlikely. Give it enough time and they will slow it down more.
The other thing is that the 100 pack was supposed to be able to charge at 200 kW. Looks like that is yet another one of Tesla's overpromises.

I believe the Model 3 and 100 pack are using the same cell chemistry.

 

[Battpower]

wonder if the folks using 250kW charging or that just bought the acceleration boost are in for a nasty surprise down the road.

They could well be mortgaging the family silver without knowing it. For Tesla it's just 'consumption' and statistics for their warranty exposure.

For owners who have outlying battery failure outside of the norm have problem of establishing that fact.

 

[Chaserr]

I kinda wonder how many of these cool features have secret, undisclosed timers on them. We have seen it with DCFC and Ludicrous/WOT launches. I wonder if the folks using 250kW charging or that just bought the acceleration boost are in for a nasty surprise down the road.

List of Tesla features with Confirmed hidden expirations:

Long Range upgrade

Performance upgrade

Ludicrous upgrade

"Full" Regen

Triple digit supercharging rates

"Free unlimited supercharging for the life of the car"

Multiple Window apps onscreen at once

EAP

Browser functionality

200kw charging on S/X 100

AP1 Smart Summon "Come find you anywhere on private property"

AP1 Navigate on Autopilot "Onramp to offramp"

Battery preheating / charge preheating when frozen

Mixed mode auto with manual settings for AC

 

[Battpower]

The other thing is that the 100 pack was supposed to be able to charge at 200 kW. Looks like that is yet another one of Tesla's overpromises.

You beat me to it posting that. Certainly I was already thinking that way. And as the EV population ages.......

 

[Chaserr]

It's very relevant, actually. Thanks.

Raging fire shuts airport in Stavanger

I didn't see "Tesla" in that article but other sources are saying a parked Model S started the fire. What are the Vegas odds on an upcoming 2020.2 update will have another round of batterygate infections?