where is the "precondition my battery" button?

[steinbej]

I've been reading here that a way to save charge for driving is precondition the battery before leaving while still plugged in to wall power. But how do I do that? On my Tesla app, I see a button for "turn on climate" and a smaller icon with the defrost symbol. But nothing about "precondition the battery before departure" or anything like it.

I'm sure there's a simple answer, but I'll have follow up questions I'm sure, which is why I'm posting rather than simply searching.

-- JS

 

[Arkilia]

When you preheat the cabin using the app the battery also warms up. There is no button for it. You can see a battery symbol in the upper right corner.

 

[Arkilia]

Like this

 

[Sebat4]

I wish there was only battery heating option. Sometimes I just want to warm up the battery istead the whole cabin.

 

[pt19713]

I wish there was only battery heating option. Sometimes I just want to warm up the battery istead the whole cabin.

Put the nearest Tesla supercharger as the nav point. Ideally a dedicated 'heat battery only' would be ideal, but this is a workaround to not heat the cabin.

 

[Rocky_H]

I do see a lot of these threads where people seem to think the burden/responsibility is on them to jump through hoops and do rituals to have to do things to take care of the battery to protect it, pre-warm it, etc. That's not really true. The car will take care of that for you. You can just hop in and go. The car will take care of limiting itself if it needs to or warming itself up or whatever as you drive. You don't need to worry about it.

These things are just for your own comfort and preferences, like if you prefer getting in a warm car, or you want to pre-waste a lot of energy because you like the feel of more regen instead of having to use your brakes some during the early portion of your drive while the car warms up.

 

[kishkaru]

The car will take care of that for you. You can just hop in and go. The car will take care of limiting itself if it needs to or warming itself up or whatever as you drive. You don't need to worry about it.

That's not true. There's a definite use case for manually pre-heating the battery, and that is when about to supercharge. If the battery is cold, you get crap supercharge speeds (usually ~130 kW or less), especially on V3 250kW stations.

"Preheating for Supercharging" only happens if you're navigating directly to a supercharger. If you're navigating to a destination, and have supercharger stops along the way, it won't preheat the battery. Thus you pull in with a cold battery and have to wait a while for it to ramp up (if at all). At least that's been my experience using Navigate.

Thus having a button to tell the car to manually heat-up the battery before arriving at a supercharger would be very useful. At least for us power users, we can use our judgement based on SoC % left to judge how early to turn on the heating vs. needing the energy to drive the car to the supercharger.

 

[LoudMusic]

"Preheating for Supercharging" only happens if you're navigating directly to a supercharger. If you're navigating to a destination, and have supercharger stops along the way, it won't preheat the battery. Thus you pull in with a cold battery and have to wait a while for it to ramp up (if at all). At least that's been my experience using Navigate.

That is incorrect at least in my experience. The car preheats the battery for every supercharger stop planned by the navigation system.

 

[kishkaru]

I did a lot of traveling during the Christmas holidays using Navigate and stopping exclusively at V3 superchargers. Never once did I see "Preheating for Supercharging" on the UI. I always pulled in at 5-10% and charged to ~50-70%. The highest speed I ever got was ~180kW.

The other explaination could be that the car knew the SoC % is too low, and didn't want to waste the energy on preheating, in case I didn't make it to the supercharger. Maybe it only does preheating if the predicted arrival SoC is higher (e.g. above 15-20%)

 

[LoudMusic]

I did a lot of traveling during the Christmas holidays using Navigate and stopping exclusively at V3 superchargers. Never once did I see "Preheating for Supercharging" on the UI. I always pulled in at 5-10% and charged to ~50-70%. The highest speed I ever got was ~180kW.

The other explaination could be that the car knew the SoC % is too low, and didn't want to waste the energy on preheating, in case I didn't make it to the supercharger. Maybe it only does preheating if the predicted arrival SoC is higher (e.g. above 15-20%)

I believe that could be part of it, as I experienced that once as well. We arrived at probably 6%. The other reason might be that the battery was just warm enough already. I had several stops across Kentucky, Tennessee, and Kansas, where the car was showing outside temp in the 30s, no preheating the battery, and within seconds of plugging in at the Supercharger we were making 150+kW.

Sometimes just using the battery might warm it enough.

 

[kishkaru]

Sometimes just using the battery might warm it enough.

I was cruising at 85mph, and outside temp was ~70F. It still wasn't hot enough by just driving.
Most of the time, I was getting ~140kW and peaked at ~180kW on V3's.

 

[pt19713]

Too bad Tesla doesn't have somewhere in the charging UI to show the actual battery pack temp. It'd make a lot of these discussions much easier.

 

[LoudMusic]

Too bad Tesla doesn't have somewhere in the charging UI to show the actual battery pack temp. It'd make a lot of these discussions much easier.

The data is definitely all available but it takes 3rd party equipment. I wish Tesla allowed a lot more screen customization.

 

[Big Earl]

I did a lot of traveling during the Christmas holidays using Navigate and stopping exclusively at V3 superchargers. Never once did I see "Preheating for Supercharging" on the UI. I always pulled in at 5-10% and charged to ~50-70%. The highest speed I ever got was ~180kW.

The other explaination could be that the car knew the SoC % is too low, and didn't want to waste the energy on preheating, in case I didn't make it to the supercharger. Maybe it only does preheating if the predicted arrival SoC is higher (e.g. above 15-20%)

180 kW is pretty good. 250 will only last for a minute or two in ideal conditions on a fresh battery pack. 180 kW on an 80 kWh battery pack is nothing to complain about.

 

[kishkaru]

To be clear, I only saw 180kW once. Most of the time it was < 150kW, usually hovering at ~130kW peak.

 

[Sebat4]

To be clear, I only saw 180kW once. Most of the time it was < 150kW, usually hovering at ~130kW peak.

I have charged in the past at 250kW SC when I was the only car there and the top I ever got was ~130kW. Same max charging speed that I get at 150kW. The only nice thing about 250kW SC is charging speed not dropping when someone is charging next to you. No A and B chargers.

 

[silverstoned83]

These things are just for your own comfort and preferences, like if you prefer getting in a warm car, or you want to pre-waste a lot of energy because you like the feel of more regen instead of having to use your brakes some during the early portion of your drive while the car warms up.

The same argument about wasting energy can be made from the other perspective. You’re wasting a lot of kinetic/potential energy during the drive that could have been turned into free electricity if the battery had only been preconditioned before departing using utility power. The amount of energy it consumes to precondition is around 2-3 kWh in a 50F garage, which I think could be equal, or less perhaps, when compared to the amount of regenerative braking energy harvested after a relatively short distance.

By not spending the energy before departing, you are preventing the car from being as efficient as it could be, which I think could be more of a waste of energy.

 

[Big Earl]

The same argument about wasting energy can be made from the other perspective. You’re wasting a lot of kinetic/potential energy during the drive that could have been turned into free electricity if the battery had only been preconditioned before departing using utility power. The amount of energy it consumes to precondition is around 2-3 kWh in a 50F garage, which I think could be equal, or less perhaps, when compared to the amount of regenerative braking energy harvested after a relatively short distance.

By not spending the energy before departing, you are preventing the car from being as efficient as it could be, which I think could be more of a waste of energy.

I think you’re overestimating the amount of regenerative energy available on a short drive (unless descending from high elevation). The driver can also compensate to maximize their available regen (don’t over-accelerate, anticipate stops, etc).

In most around-town cases, preheating the battery is going to use more energy than can be recovered through additional regen (above the limited amount available when cold). There are, of course, situations where preheating makes sense, including descending a mountain, personal comfort, preparing to DC fast charge, and when it’s cold enough that no regen would be available.

 

[dsnows]

That is incorrect at least in my experience. The car preheats the battery for every supercharger stop planned by the navigation system.

my experience too.

 

[LoudMusic]

my experience too.

Yep - just experienced it yesterday. It was kind of funny - I had stopped at a location, and then needed to return home so put in the home address. It routed us to a SuC about 25 miles away and started preconditioning immediately because it was so cold outside and the car had been sitting parked on ice for about an hour and a half. I've never seen it precondition so early.

We arrived at the supercharger where only shared stalls were available so we started charging at 65kW I think? When the other car left it jumped to around 120kW before tapering off as we reach high SOC and then departed ... straight into standstill traffic.