New MYP Owner: Learning Curve Tips Thread

[Watts_Up]

If there's a lot of supercharger close together you can arrive a 5% and leave at 35% which makes your stops very fast like around 5 minutes.

This works only in areas with high density of Superchargers located right by a freeway exit, and driving alone, because
in general, if you have passengers, they would like to stretch their legs, and also use a restroom or eat something wen you stop.

Most generaly when driving cross country, Supercharger locations are quite sparse, and not always next to an exit.
You need also to get an higer charge, just in case there is an accident or a road construction forcing you making a detour.
Also weather conditions, in particular high wind, can increase a lot your consumption.
And driving at high speed, especially above 80-85 mph will affect your pre-estimated range.

Something you didn't mentioned is that below 20% preconditioning will not be activated, affecting you charging time otherwise.
So when preparing a trip using A Better Route Planner, I like to selected my next stop with still having about 30% of charge,
for all the above reasons. Most of the time, I take advantage of a charging stop to also eat someting, so charging time up to 70-80%
is not an issue, while my passengers also apreciate a lower number of stops.

In fact, because of the additional rest time, after a long journey trip, I feel much more relaxed
and don't feel too tired compared with a similar trip using an ICE car and making a lower and shorter number of stops.

 

[MacO512]

That is the general strategy I use but going that low for your SoC (state of charge) will accelerate the battery wear. I normally never go below 15-20% and out at about 50-60% depending on the leg.

Where did you hear minutes at 5% causes battery wear? I've heard that's a myth. Remember even 0% on the vehicle has a buffer with more power available plus a buffer in the pack that's unusable.

 

[DayTrippin]

There are a lot of sources. Battery university has a lot on how to maintain Li-ion batteries. Even recurrent auto says right on their dashboard to keep it between 30-80%. Here is a quote from my dashboard with my average charging rate since I've owned the car. Recurrent is pulling data from a lot of cars and running the numbers on it. They did the recent supercharger study linked below.

Recurrent can monitor your battery degradation for you. My M3 LR that is about 20 months old now is showing less than 1% degradation. I've almost never charge above 80% and almost never below 20%. Most of the time I kept it 50% and charge up just enough to cover my miles I plan on driving for the day. So if I think I'll use 20% of my pack, I charge up 10% above 50% to 60%, I'll then come home at about 40%.

This keeps me centered around the idea of an average SoC of 50-55%. I keep it closer to 50 in the summer since the weather is hotter and heat is the enemy of these batteries. While the car can actively cool the pack, it allows the pack to get warmer if not plugged in to save battery. Lower SoC are more tolerant of higher temps. Another reason to leave your Tesla plugged in all the time even when not charging if you can.

I plan to own my cars for a long time so degradation is important to me. Even if I didn't, no point wasting such a valuable resource and recycling these batteries isn't easy. So even if I do sell my car, there will be more life in it just by maintaining the pack, and we end up with less debris in landfills.

From my recurrent dashboard:
"How am I charging?
To minimize battery degradation, we recommend that you aim to keep your charge between 30% and 80%

51% average charge"​

A great read here on helping with degradation. Look at the DoD graph (depth of discharge). Look at figure 6 but I encourage you to read the entire page.

BU-808: How to Prolong Lithium-based Batteries

BU meta description needed...

batteryuniversity.com

Full Speed Ahead: EV Study Reveals Impacts of Fast Charging

www.recurrentauto.com

 

[MacO512]

There are a lot of sources. Battery university has a lot on how to maintain Li-ion batteries. Even recurrent auto says right on their dashboard to keep it between 30-80%. Here is a quote from my dashboard with my average charging rate since I've owned the car. Recurrent is pulling data from a lot of cars and running the numbers on it. They did the recent supercharger study linked below.

Recurrent can monitor your battery degradation for you. My M3 LR that is about 20 months old now is showing less than 1% degradation. I've almost never charge above 80% and almost never below 20%. Most of the time I kept it 50% and charge up just enough to cover my miles I plan on driving for the day. So if I think I'll use 20% of my pack, I charge up 10% above 50% to 60%, I'll then come home at about 40%.

This keeps me centered around the idea of an average SoC of 50-55%. I keep it closer to 50 in the summer since the weather is hotter and heat is the enemy of these batteries. While the car can actively cool the pack, it allows the pack to get warmer if not plugged in to save battery. Lower SoC are more tolerant of higher temps. Another reason to leave your Tesla plugged in all the time even when not charging if you can.

I plan to own my cars for a long time so degradation is important to me. Even if I didn't, no point wasting such a valuable resource and recycling these batteries isn't easy. So even if I do sell my car, there will be more life in it just by maintaining the pack, and we end up with less debris in landfills.

From my recurrent dashboard:
"How am I charging?
To minimize battery degradation, we recommend that you aim to keep your charge between 30% and 80%

51% average charge"​

A great read here on helping with degradation. Look at the DoD graph (depth of discharge). Look at figure 6 but I encourage you to read the entire page.

BU-808: How to Prolong Lithium-based Batteries

BU meta description needed...

batteryuniversity.com

Full Speed Ahead: EV Study Reveals Impacts of Fast Charging

www.recurrentauto.com

Thanks for the detailed post I'll have to read about this more.

After the last few months of research on NCA batteries I now keep my Tesla charged at 50% daily but for longer travel days set scheduled departure for whatever extra is needed to complete just before I leave.

I don't regularly go below 30%, it would just be the 5% target for literally minutes until I very quickly arrive at a supercharger, and that would be a series of stops probably only 2-5 times a year on very long road trips.

It seems like much of this research is for hundreds or thousands of continuous 80%/100% Depth of discharge cycles - I'd probably only have one of these (starting trip at 100% down to 5%) then a bunch of 5%-45% or so cycles. The 5-45% cycles are the same depth of discharge as a 30-70% cycle, but its saves significant time at the charger from riding the higher kw rate of the charging curve.

I'm not completely convinced the 5% depth of charge is any worse than 30-70%, but I do suspect if it is worse that is such a small fraction of a percent difference in degradation over 5 years that its extremely likely for me to be well worth the reduced time sitting at supercharger stops on very long trips.

I'm all for reducing degradation, especially when storing the vehicle. But once it interferes with my schedule I become very leery of accepting those possibly more theoretical tradeoffs. I might keep my Tesla for over 100k miles or longer, but I haven't kept any of my last 7 vehicles I've owned for more than 40k miles so honestly odds are any degradation will never impact me.

Much appreciate you responding with research instead of insults and opinion though!

 

[Mateo83]

Where did you hear minutes at 5% causes battery wear? I've heard that's a myth. Remember even 0% on the vehicle has a buffer with more power available plus a buffer in the pack that's unusable.

I've run it down to single digits intentionally a few times recently to rebalance the pack and got 10 miles back on mine.