Daily charge of 86% / Weird charge % on app

[Russinating]

Moderator comment - original thread merged with 'Weird charge % on app'

Sorry guys, I'm sure this has been mentioned elsewhere but I tried a search and couldn't find it.

I noticed the daily charge threshold/line via the app is now 86% rather than 80%, with trip now being in the 86-100% range.

When did this come in and is there a reason for the change?

 

[NorfolkMustard]

It seems to drift a bit - it's your car & app rather than a global change, each car is a little different - temp etc. It may go back tomorrow / when it warms up or you drive it.

mine is currently showing 89% in the iOS app, but if I look in the Tesla API it's recording it at 90%

The difference in my case is due to temp. The Tesla api is recording my current battery level as 82, but useable as 81. That 1% is affecting the slider bar on the app and displaying how much of a 90% battery would be useable (89%)

'outside_temp' => 8.0,
'usable_battery_level' => 81,
'battery_level' => 82,
'charge_limit_soc' => 90,

Guessing yours has a temp adjustment of 4% currently.

 

[pdk42]

Tried to set charge on car tonight and noticed that when sliding the limit to max, it's not 100%. Likewise, the "Daily" band now stops at 73%, whereas it used to be 80%. Anyone know what's going on?

 

[Medved_77]

Part of your battery has been "reserved" by the cold weather.

Just set it to the % you usually would and preheat the car in the morning if it's still cold.

 

[NorfolkMustard]

The blue band gives the answer, it's adjusting for cold. battery capacity versus useable capacity

see Daily charge of 86% moderator comment - now merged

 

[pdk42]

Even more weird, although I've set the % to 73% in the app (top end of daily), charge time is predicted as much longer than I would have expected, and Teslafi is reporting limit as 90% not 73%. I suspect the app is doing some sort of adjustment, perhaps for temperature - but it's very confusing.

 

[NorfolkMustard]

What do you disagree with @DaminGJ ?

 

[NickFie]

Charging will take longer because some of the power will be used to heat the battery to proper temperature for charging.

The battery cells are little chemistry labs. They must be within appropriate temperature range to charge safely, swiftly and without damage to the cell components.

This is different from strictly mechanical pumping used to fill an ICE fuel tank.

 

[Russinating]

So is the advice to charge to the same % or the trip limit? This is prior to embarking on a journey of course.

 

[GRiLLA]

Once the battery warms up the blue segment will come back. If your journey is more than an hour or you pre condition the car then assume your range will come back. If you won't be able to complete your journey in the amount of green show, and its not far enough to warm the battery then charge.

 

[pdk42]

I'm still confused by this, so bare with me.

So the battery is at 23% or whatever and cold. I want to charge it to 80%, normally at the end of the "Daily" range. So I do that but the app says 73%. So I move the slider more and it gets almost to full before I see 80%.

Confused I move it bsck to 73% and go to bed. The car charges to 80% anyhow. I'm assuming if I had left it at the higher level (81% indicated) it would have charged to 100%.

This behaviour sounds like a bug to me. I understand that the app wants to show me a lower usable charge level when it's cold since I'll get less range. But when it charges, the first thing the BMS does is warm the battery and I get the % charge I expect. At present the app's behaviour leads to the battery being charged well past the indicated level. I contend that the app should not apply this correction when setting charge level since it gets it wrong.

 

[Mr H]

I'm still confused by this, so bare with me.

So the battery is at 23% or whatever and cold. I want to charge it to 80%, normally at the end of the "Daily" range. So I do that but the app says 73%. So I move the slider more and it gets almost to full before I see 80%.

Confused I move it bsck to 73% and go to bed. The car charges to 80% anyhow. I'm assuming if I had left it at the higher level (81% indicated) it would have charged to 100%.

This behaviour sounds like a bug to me. I understand that the app wants to show me a lower usable charge level when it's cold since I'll get less range. But when it charges, the first thing the BMS does is warm the battery and I get the % charge I expect. At present the app's behaviour leads to the battery being charged well past the indicated level. I contend that the app should not apply this correction when setting charge level since it gets it wrong.

Just set it at the normal 80% daily limit and as the battery warms whilst charging it will come back to the expected limit, ignore the 72% as that will change automatically as the battery warms up. What you’re seeing is the range available ‘now’ with a cold battery which will change as it warms.

 

[GRiLLA]

It's a bit weird when setting the limit. Just set it to the normal notch and ignore it.

 

[pdk42]

Just set it at the normal 80% daily limit and as the battery warms whilst charging it will come back to the expected limit, ignore the 72% as that will change automatically as the battery warms up. What you’re seeing is the range available ‘now’ with a cold battery which will change as it warms.

It's a bit weird when setting the limit. Just set it to the normal notch and ignore it.

Yeah, I guess that'll work - but I still contend it's a bug. Showing the usable % (after cold correction) makes perfect sense if you want to show range, but not if you want to set charge limit.