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What should my ideal charge percentage be?

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Well, for 28amps, you are getting about what you should be getting. The real problem is you should be getting more than 28amps from the HPWC in the first place. I have a feeling it's set low or the electrician screwed up somewhere else.

NEMAs_Table.png
 
electrician cam back by, so its now at 240v, 48amp, and 34mi/hour, is this more normal?
we finally looked the RTFM, which i honestly thought was a switch or something and had to google it... LOL
i have a model s p90d, 2015.
If the circuit breaker installed is 60amps, then the car will pull 48amps from a properly configured HPWC. The code for continuous draw is 80% of max, so 80% of 60amps would be the 48amps you are seeing.
 
The US Army study is on the Roadster chemistry (LiCoO2) and the NREL study is on the Model S chemistry (NCA). Both studies have similar results, and Tesla battery management is similar for both the Roadster and Model S, so the general principles can be applied to both.

The Battery Management System tries to keep the battery above freezing and below 104F. The US Army study has three runs, one at 32F, one at 68F and one at 104F, so it's an excellent match for the BMS range and can be used to bracket what we'd expect to see in the real world.

The overall conclusion is that low temperatures and low SOC help extend battery life, and high temperatures and high SOC reduce battery life. Both in combination are especially bad. A low SOC can help protect against high temperatures and low temperatures can protect against a high SOC.

Even Elon said the batteries should last forever in Alaska. If you're in a warmer State (or have a hot summer) then lowering the SOC will help protect the battery.

Personally I don't think this is too complex for the average person, but will take some education. I think it's mostly about managing expectations for potential buyers.

When I bought my Roadster I expected the battery capacity would drop to 70-80% over 8 years. If I run at 90% Standard Charge in a warm climate that's probably true. Now that I know I can get better numbers by dropping the SOC I'm a very happy camper, especially since I don't need the full Standard range on a daily basis. So far I've seen no degradation after three years by running at 50%.
However, there is the idea that low temperatures and high SoC can induce Li plating. Anyone have thoughts on that?
 
Well, for 28amps, you are getting about what you should be getting. The real problem is you should be getting more than 28amps from the HPWC in the first place. I have a feeling it's set low or the electrician screwed up somewhere else.

NEMAs_Table.png
i only had a certain amount of current or something, kinda naive here, to address to the tesla part becuz of a/c and other electrical stuff i guess... if this seems normal, then i def feel better about it. My theory was, i sleep, then when i wake up , its charged; which now seems like is logical at 34mi/hour...
 
i only had a certain amount of current or something, kinda naive here, to address to the tesla part becuz of a/c and other electrical stuff i guess... if this seems normal, then i def feel better about it. My theory was, i sleep, then when i wake up , its charged; which now seems like is logical at 34mi/hour...
Here's what the manual says for settings.

Screen Shot 2019-07-08 at 7.06.18 PM.png
 
You guys are all overthinking this. If you don't need or want the control, set it to 90% or whatever and don't fiddle with it. We're talking about a relatively small difference over the life of the pack.

I agree. I have a 2015 Model S 70D that will be 4 years old this October. My loss maximum travel miles has decreased from 285 to 283. I keep my charge level at 200 miles for daily which is roughly 70%. I still have over 5 years of warranty life left, so I am really not worried about it. i believe I can get 12 to 15 years out of this pack. I will have another Model S by that time or whatever Tesla current model monicker is available.
 
I agree. I have a 2015 Model S 70D that will be 4 years old this October. My loss maximum travel miles has decreased from 285 to 283. I keep my charge level at 200 miles for daily which is roughly 70%. I still have over 5 years of warranty life left, so I am really not worried about it. i believe I can get 12 to 15 years out of this pack. I will have another Model S by that time or whatever Tesla current model monicker is available.

I find this hard to believe... the Model S 70D range was 240 when brand new. :cool: Tesla Model S - Wikipedia

upload_2019-7-25_16-32-30.png
 
How are you calculating your range... rated or ideal?

I am not calculating anything. When i charge the Model S to 100% the range is showing 285. You don’t want to use ideal anyway because it is not real world. Even rated is not accurate since driving habits have a lot to do with total driving range. If you drive like a wild man, your travel miles are going to decrease significantly. At least in my experience.

I have a setting for Chill and Standard. I keep my setting on Chill. Still has plenty of power, but conserves battery depletion. I also don’t run daytime running lights. I keep the AC at 72 degrees. I accelerate with an egg under my foot. I take advantage of regenerative breaking to put back energy into the battery.

Generally speaking on my Model S I have observed if I keep the speed at 65 on the interstate, during daylight hours, I only lose about 10 to 15% of total mileage that is used to power other items (a/c, main screen, dash screen, etc ..) So net driving miles at the high level is about 240 miles. I believe Tesla places a Supercharger around every 140 to 160 miles apart.
 
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Generally speaking on my Model S I have observed if I keep the speed at 65 on the interstate, during daylight hours, I only lose about 10 to 15% of total mileage that is used to power other items (a/c, main screen, dash screen, etc ..) So net driving miles at the high level is about 240 miles. I believe Tesla places a Supercharger around every 140 to 160 miles apart.
You’re not “losing” mileage to power other items, (except a little for A/C and more for heat which wouldn’t apply in Florida). You’re using more energy to propel the car at a speed faster than the EPA test cycle. If you would drive the EPA test cycle you would get the rated range. That’s what rated range means.
 
You’re not “losing” mileage to power other items, (except a little for A/C and more for heat which wouldn’t apply in Florida). You’re using more energy to propel the car at a speed faster than the EPA test cycle. If you would drive the EPA test cycle you would get the rated range. That’s what rated range means.

I understand that. I drive 65 which is the rated speed by EPA.
 
electrician cam back by, so its now at 240v, 48amp, and 34mi/hour, is this more normal?
we finally looked the RTFM, which i honestly thought was a switch or something and had to google it... LOL
i have a model s p90d, 2015.

With my Model S destination charger here is what I get:

240v at 40 amps on a 50 amp breaker.
Charging rate is 37 mph
Power rate utility co. $0.12/kWh
 
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No it’s not. The EPA test cycle is a complex pattern of multiple speeds for different amounts of time, and none of them are as high as 65 mph.

I really don’t care about all the weed dipping. I’m done with this argument trying to say what is right or wrong. I just know what happens with my Model S. I am sure you know what happens with your Tesla. Have a good day.