Any value in varying charge rates on a daily/weekly basis (other than at 80%)...

[Schwachs]

I've read a bunch and understand that for best long term battery life, it's best to not charge the Tesla past 80% on a regular basis...

My question is if there's any value on charging to different %s - but under 80% - on a regular basis?

Aka, I come home and plug it in and it stops at 80 - but does it make any sense to go to 60% for a week and 70% another week etc... (If range isn't an issue...)

Thanks!

 

[JasJ]

I doubt varying does much as long as you stay below 80%.

Some good reading:
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries

Figures 6 and 7 are pretty interesting:

100% SOC has quite the impact on capacity retention over time.

I aim for 45-75% battery state most of the time.

 

[whitex]

I doubt varying does much as long as you stay below 80%.

Some good reading:
How to Prolong Lithium-based Batteries - Battery University

Figures 6 and 7 are pretty interesting:

100% SOC has quite the impact on capacity retention over time.

I aim for 45-75% battery state most of the time.

If we were to apply the above data to Tesla cars, given most people charge once a day, after 10 years (3650 cycles) best to worse is 13% of battery capacity gain. If course you are unlikely to always have the car stay between 65-75% (the best curve) every single day of the 10 years, so chances are your gain is less than the best case scenario of 13%. I suspect at 10 years there will be other aging factors involved, hence stopped worrying about this long time ago. Have been charging all cars to max daily range (90%) and haven't seen much degradation - oldest Tesla we still have is approaching 3 years old. Very occasionally we even charge to 100% for trips.

 

[TexasEV]

There is no problem charging past 80%. Just don’t charge to 100% frequently and let it sit there. Practical experience with Model S over the past 5 years shoes minimal degradation no matter what people charge to. Don’t overthink this. Just enjoy your car.

 

[Schwachs]

Ok thanks all!

 

[pinball_player]

If we were to apply the above data to Tesla cars, given most people charge once a day, after 10 years (3650 cycles) ...(snip)

Actually a cycle consists of a complete discharge to complete charge. If you add 25% to the car every day, then you use a full cycle every four days. So unless you are driving the full range of the car every day, you are not using a full cycle.

 

[whitex]

Actually a cycle consists of a complete discharge to complete charge. If you add 25% to the car every day, then you use a full cycle every four days. So unless you are driving the full range of the car every day, you are not using a full cycle.

These graph curves appear to have defined the charge cycle per curve with 75%-65% being the optimal cycle and 100%-20% being the least optimal. I assume they count the optimal cycles, but if you are right and they count and equivalent of 100 cycles, that would make the maximum benefit of 10 years of optimal charging even less (sub 8% from the chart), so even less of a reason to fuss over it.

 

[LCR1]

Actually a cycle consists of a complete discharge to complete charge. If you add 25% to the car every day, then you use a full cycle every four days. So unless you are driving the full range of the car every day, you are not using a full cycle.

Don't know about Tesla I but I remember apple saying this about their phones a few years ago, 50-100 was 1/2 of a charge 25-100 was 3/4 charge cycle, etc. And that most people would incorrectly count days, when they needed to count charge cycles. One could probably google the Dynamic Stress Test(DST) that is mentioned in the graphics and see what the criteria of that test/cycle is, I don't remember off the top of my head.

Either way, I just changed my charge limit form 90 to 75 my daily commute is 40-50 miles so it won't kill me.

 

[Black96z]

You ever get the P85 LCR1?

 

[LCR1]

You ever get the P85 LCR1?

Nope, I was out in the Gulf when it finally got fixed. They called, left no voice mail(no way to see only missed calls), then got an email saying they were releasing it. Ended up getting a CPO 70D