Hi - quick question. Is it a best practice to precondition the battery by setting a departure time each morning before beginning my commute? Curious if heating (or cooling) the battery each day before setting off helps prevent battery degradation over several years, or if this is actually just more wear and tear on the battery and might be best avoided accept when setting out on long trips/approaching a supercharger. Thanks!
-
Want to remove ads? Register an account and login to see fewer ads, and become a Supporting Member to remove almost all ads.
Preconditioning Battery for Daily Commute - Good or Bad for Battery Long Term?
- Thread starter YNot??
- Start date
bluenycom
Member
There are 2 kinds of "precondition", the cabin and battery. When you program departure precondition, it mainly preconditions the cabin for your comfort using home power instead of the battery. You could argue that this would help prolong the battery since it's not using the battery to precondition the cabin when plugged in. It does precondition the battery if its really cold to optimize the battery. I see you live in LA so it really doesn't matter.
The other precondition for battery is in preparation for supercharging. This doesn't happen at home with level 2 charger. It mainly warms the battery up so it can handle a large amount of electricity transfer. Even if it didn't precondition for supercharging, it would just charge slowly until it warms up. It just takes longer to supercharge if not preconditioned.
The other precondition for battery is in preparation for supercharging. This doesn't happen at home with level 2 charger. It mainly warms the battery up so it can handle a large amount of electricity transfer. Even if it didn't precondition for supercharging, it would just charge slowly until it warms up. It just takes longer to supercharge if not preconditioned.
Last edited:
E90alex
Active Member
The battery gets much warmer when driving than it does when you “precondition” it. Preconditioning is mainly for cabin comfort.
Supercharging precondition is a different thing and is only triggered automatically when you navigate to a supercharger.
Long story short, don’t worry about it. You can’t really manually “precondition” the battery in any significant amount.
Supercharging precondition is a different thing and is only triggered automatically when you navigate to a supercharger.
Long story short, don’t worry about it. You can’t really manually “precondition” the battery in any significant amount.
gx9901
Active Member
I doubt the car actually heats the battery during precondition in LA very often. Here in MN I set the car to precondition every morning before I leave for work during the colder months and when it's below certain temperatures (seemingly below 40F or so) it heats the battery while heating the cabin. I have no concerns about this. I think it's better for the battery to get up to a good operating temperature BEFORE driving than doing so WHILE driving.
Helpful comments! It’s been in the 30s the last several weeks in the morning at my place in LA, so not too dissimilar from when I used to live in Minnesota! The primary advantage I’ve noticed with preconditioning for a specific departure time versus just manually heating the cabin a few minutes before I go by turning the climate control on is that the regenerative braking isn’t reduced when I precondition prior to departure. I assume this is because the battery is also warmed up.
E90alex
Active Member
That’s correct. It will do some battery heating but it’s still not fully heated to the temps it would be when driving it.
gx9901
Active Member
Interesting that you lived in Minnesota before! Yes, warming up the battery increases regen braking, although with the blended braking setting available now, it doesn't matter as much. Another benefit of having the battery warmed up while plugged in at home prior to departure is that your efficiency on that drive will be better compared to driving on a cold battery and also the max power output is higher at the same time.
No wear on the battery so you might as well use scheduled departure preconditioning if you have a fixed weekday or every day schedule. Most battery degradation is due to aging of the battery especially over the first 5 years.
You can't control whether the Tesla Model Y will warm the battery during preconditioning. The Tesla Model Y now preconditions to a lower target battery temperature. This strategy reduces the time needed to precondition the battery before driving and saves energy. The battery's efficiency is improved with some amount of battery warming. Also, the Tesla Model Y can deliver full acceleration with a warm battery although in regular driving you may not notice any loss of power if the battery is cold except perhaps when passing.
In the Tesla Model Y you used to have to choose between fully preconditioning before driving and preconditioning for a shorter (more convenient length of time) but likely having reduced regenerative braking. Now that you can enable blended friction braking to be active when regenerative braking is limited or unavailable you can drive without preconditioning and the Tesla Model Y will slow down when you let off on the accelerator pedal about the same as when regenerative braking is available.
You absolutely want to precondition for Supercharging as this is the fastest, most efficient use of the Supercharger. To precondition for Supercharging you need to set the Supercharger as the destination or next stop in the Navigation system.
Some Tesla owners believe that preconditioning while parked, plugged uses power from the grid, not from the battery. This is not the case as all power used for the HVAC compressor and to warm the battery via stator heating takes high voltage and power that can only come from the battery. The power drawn from the battery during preconditioning is replenished via grid power. Charging at Level 1,120V (maximum of 2kW) and charging at Level 2, 240V (up to 11.5kW) can't supply all of the power used during preconditioning. The Tesla Model Y HVAC compressor can draw up to 7kW and an additional 7kW is used generating heat to warm the battery using the motor stators, in total this can exceed 14kW. The only source of that much power in the Tesla Model Y is from the battery (unless Supercharging.) Even while Supercharging, the power for preconditioning comes from the battery and the Supercharger charging session replenishes the battery.
Last edited:
@jcanoe : not pre conditioning for supercharging could have an adverse effect on battery health ? I know that it’ll impact charging speed which Tesla reduces to protect the battery. But even with the charging speed throttled, could it impact the battery negatively if it’s not preconditioned ?
There is no cause for concern. The Tesla Model Y's battery management system (BMS) manages the complete charging session from beginning ramp up to peak charging rate and then tapering down. The BMS will monitor the state of the battery throughout the charging session. Even if you don't precondition your Tesla Model Y for Supercharging before beginning a Supercharger charging session the BMS may perform some battery heating during the Supercharger charging session. This ensures optimal charging. Also, the BMS can access Tesla's charging history data that includes every Supercharger charging session performed on the battery pack in your Tesla vehicle. The BMS will not expose the battery pack to excessive charging rates that would stress the battery. At extreme low temperatures Supercharging charging can take some time to begin charging while the battery is being warmed, then charge at ~20kW charging rate (a small fraction of the maximum charging rate when Supercharging) for a time while gradually ramping up the charging rate. At lower battery pack temperatures the charging rate would never approach the maximum rate.
Thanks for the confirmation.
I usually don’t pre condition my M3 when charging at a nearby supercharging in order to buy some time to do what I have to do. Else it’s just too quick for comfort.
On road trips, it’s a different story and the opposite holds true.
Similar threads
