Wiki Sudden Loss Of Range With 2019.16.x Software

[mthoring]

maybe this was described in the paper or before in the thread, but I cannot recall I have seen it. So if they are not sure they are reading voltages correctly, how is it that they know reliably it is charged to 4.2v? or potentially not?
I know there was a discussion about "not-existing range" at the bottom due to errors in measaurement, but are you saying for some reasons lower voltages are not reliably measured but higher are?

Explaining Changes post-firmware 2019.16 Regarding Range Loss | wk057's SkieNET

Edit:
<removed snippets>
Short version: The BMS calculates an approximate voltage value using other sensor readings. The algorithm accounts for a (small) margin of error which means a small cap might remain in place on allowed vmax.

 

[JRP3]

Hyundai Officially Confirms Folded Anode Tab Caused For Kona EV Fires

According to Hyundai, it was indeed a folded anode tab in the batteries that caused the fires.

 

[Chaserr]

Anything over no cap is illegal without a recall exemption. And recall exemptions like GM and Hyundai are only short term until the cap can be completely removed safely. Tesla didn't derate our batteries or sell them with a cap to wiggle around.

They do now, and this is probably why.

 

[mymagiccarpet]

Explaining Changes post-firmware 2019.16 Regarding Range Loss | wk057's SkieNET

Edit:
<removed snippets>
Short version: The BMS calculates an approximate voltage value using other sensor readings. The algorithm accounts for a (small) margin of error which means a small cap might remain in place on allowed vmax.

Thanks. Yes, so that's what I'm wondering about. We are discussing how sensor measurement may not be 100% reliable at some voltage well below 4.2V. But doesn't that mean that same error could have happened at 4.2V? And if it's measuring 4.2, but it's actually higher than that, what happens?

 

[Chaserr]

if it's measuring 4.2, but it's actually higher than that, what happens?

An abundance of caution, an investigation, a whole slew of crippling battery nerfing updates...

They didn't reduce maximum battery charge to stop it from going too low.

 

[sorka]

It's been a few weeks for me since updating from my 3 year old software to current software with the MCU2 upgrade. I've lost no capacity. I've charged to 100% a few times now due to the dramatically slower supercharging rates as a way to compensate and not lose quite as much time. I'm not interested in taking care of the battery any more.

The other change was a drop in maximum battery current from 1525 amps to 1500 amps. At 1525 amps, my maximum power at 90% and a battery at 110F was 455 kw vs 415 kw under the same conditions. This represents about a 9.6% increase in power which is pretty close to the 10% increase promised on the P85D Ludicrous pre-order page.

At 1500 amps, this represents about a 7.3% increase over the 1350 amp battery.

The red/orange/yellow lines show my normal supercharging speed before the software update. The blue/green/purple lines are after.

It appears that my supercharging is quite a bit slower than the fleet chart shows for current 85 cars.

 

[Florian500]

It appears that my supercharging is quite a bit slower than the fleet chart shows for current 85 cars.

Below 50% SoC kW = 105 - SoC, "equality" at 55kW:55%, then kW = 110 - SoC like lots of other 85ers with current 2020.48.37.1

(ignore the dip, V2 stall sharing is still a mystery to some people)

 

[Droschke]

The other change was a drop in maximum battery current from 1525 amps to 1500 amps. At 1525 amps, my maximum power at 90% and a battery at 110F was 455 kw vs 415 kw under the same conditions. This represents about a 9.6% increase in power which is pretty close to the 10% increase promised on the P85D Ludicrous pre-order page.

A bit confusing to me. Your amp and kW decreased but your power has increased by 9.6%?

 

[sorka]

A bit confusing to me. Your amp and kW decreased but your power has increased by 9.6%?

No. I said the initial upgrade gave me a 9.6% increase in power. The software I'm on now dropped amps from 1525 to 1500 resulting in about a 7.3% increase in power over having 1350 amps.

 

[sorka]

Below 50% SoC kW = 105 - SoC, "equality" at 55kW:55%, then kW = 110 - SoC like lots of other 85ers with current 2020.48.37.1

I'm not seeing anything as low as a starting 85KW with 20% SOC in the fleet graphs.

 

[aerodyne]

I'm not seeing anything as low as a starting 85KW with 20% SOC in the fleet graphs.

Today, with packs temp at 102 Deg F, SoC at 27%, I saw high 90's, then settled at 89 for a while.

SoC plus power in excess of 110 untill I disconnected at 62% SoC.

 

[sorka]

Today, with packs temp at 102 Deg F, SoC at 27%, I saw high 90's, then settled at 89 for a while.

SoC plus power in excess of 110 untill I disconnected at 62% SoC.

Mine starts at 80KW at 27%. Certainly nowhere near high 80s let alone high 90s...not even for a second.

 

[sorka]

So as an experiment, I charged to 80% at the new supercharger in Merced today. I drove home and parked it at 76%. I'd normally never let it sit that high but I'm perfectly fine with letting it sit at 70% normally.

That was 3 hours ago. The pumps have been running the entire time and the system drawing 224 watts of power continuously so that will be 1 kWh every 4.5 hours or 5.3 kWh / day or 17.3 miles per day until it decides the SOC is low enough to shut off the pumps. It's not running fans, heater or AC. Its JUST running the pumps. I can't think of any reason for this unless it's some sort of protection a single cell thermal runaway where it's trying to distribute the heat from a single cell that's deciding it's going to self destruct. Battery temp is 85F currently so maybe it's based on how warm the pack is as whole rather than SOC.

My range is still unchanged and is exactly what it was when I was on the 2018 release.

 

[aerodyne]

Mine starts at 80KW at 27%. Certainly nowhere near high 80s let alone high 90s...not even for a second.

Usually the case with mine too, but pack was quite warm today at 102 deg.

Less than 3000 KwH DC charging, 39k miles.

 

[aerodyne]

So as an experiment, I charged to 80% at the new supercharger in Merced today. I drove home and parked it at 76%. I'd normally never let it sit that high but I'm perfectly fine with letting it sit at 70% normally.

That was 3 hours ago. The pumps have been running the entire time and the system drawing 224 watts of power continuously so that will be 1 kWh every 4.5 hours or 5.3 kWh / day or 17.3 miles per day until it decides the SOC is low enough to shut off the pumps. It's not running fans, heater or AC. Its JUST running the pumps. I can't think of any reason for this unless it's some sort of protection a single cell thermal runaway where it's trying to distribute the heat from a single cell that's deciding it's going to self destruct. Battery temp is 85F currently so maybe it's based on how warm the pack is as whole rather than SOC.

My range is still unchanged and is exactly what it was when I was on the 2018 release.

During similar circumstances, the pumps slow down from 100% at just under 75% SoC.

I'd be curious if in your case, they are still at 100% at less than that, and when they eventually shut off...

 

[sorka]

During similar circumstances, the pumps slow down from 100% at just under 75% SoC.

I'd be curious if in your case, they are still at 100% at less than that, and when they eventually shut off...

How can I tell the pump speed?

So at 75% it seemed to have instantly stopped but it turns out the pumps are still running but just really slowly. I had to put my ear right up to the firewall inside to hear it still. Car is now drawing about 96 watts but 70 watts of that is always being drawn even with the pumps are completely silent.

 

[aerodyne]

How can I tell the pump speed?

So at 75% it seemed to have instantly stopped but it turns out the pumps are still running but just really slowly. I had to put my ear right up to the firewall inside to hear it still. Car is now drawing about 96 watts but 70 watts of that is always being drawn even with the pumps are completely silent.

Using SMT...my guess is your battery pumps are running 23%, and power train pumps are off. They should shut off completely when the car sleeps.

The 70w might just be charging up the 12v.

My vampire drain is about equal to 50w.

 

[sorka]

Using SMT...my guess is your battery pumps are running 23%, and power train pumps are off. They should shut off completely when the car sleeps.

The 70w might just be charging up the 12v.

My vampire drain is about equal to 50w.

I already have SMT installed. Let me run out and check.

It says battery pump 1 and 2 are at 0%. I can still hear the faint whirling inside the firewall but I think it's actually coming from behind the MCU.
Earlier, above 75%, I could easily hear liquid circulating when it was louder.

 

[wk057]

What they don't tell you about the MCU2 retrofit is the higher vampire drain on pre-Q2-2015 vehicles because the battery packs don't have the standby power supply DCDC which powers the MCU's standby power and body control module directly from the HV battery. The standby supply means the main contactors can stay open (saving ~20-30W IIRC). Without it they have to stay closed, a pump has to run to cool the DCDC, etc. (Yeah, a pump has to run any time to contactors are closed to circulate coolant through the DCDC... so... yeah).

MCU2 was only originally installed in cars with this standby supply and seems to behave... oddly... in cars that don't have it. As in, it stays awake more than it should.

I figure they'll fix that eventually.

 

[aerodyne]

I already have SMT installed. Let me run out and check.

It says battery pump 1 and 2 are at 0%. I can still hear the faint whirling inside the firewall but I think it's actually coming from behind the MCU.
Earlier, above 75%, I could easily hear liquid circulating when it was louder.

Very rarely, the power train pumps will run after the pack pumps are off.

My MCU fan comes on very rarely, like when I park outside and forget to cover the car.