Range Loss Over Time, What Can Be Expected, Efficiency, How to Maintain Battery Health

[Candleflame]

How long do you need to sit above 85% for the cells to balance, ballpark hours figure

This is for the Model S:

And remember the resistive bleed circuits are pretty delicate in their load. The 4 158 Ohm resistors in parallel are 39.5 Ohms with the cell Voltage about 4 Volts, that means the bleed current is about 0.1 Amp, dissipating about 0.4 Watts. The Amp-hour capacity of these packs is about 85 kWh / 370 Volts or about 230 Amp-hours. That means that it would take 2.3 hours to bleed 0.1% off of a set of paralleled cells. That's a very delicate and gentle balance that only works in a reasonable time, if the cells are almost matched to start with.


The Model 3 has way weaker bleeding circuits to give less vampire drain (i seem to remember 1/10?).
However. it depends how much imbalance there is to start with and noone here ever provides much evidence that their battery is truly out of balance.
The imbalance can be easily read out with SMT and noone here has ever shown that their battery is significantly non balanced, even when spending virtually no time above 85%.

 

[AAKEE]

How long do you need to sit above 85% for the cells to balance, ballpark hours figure?

That would depend on how much imbalance you have.
For normal imbalance, perhaps 2-3 hours is enogh as it seems.
[Edit] beaten by @Candleflame on the answer

 

[Steve446]

That would depend on how much imbalance you have.
For normal imbalance, perhaps 2-3 hours is enogh as it seems.
[Edit] beaten by @Candleflame on the answer

Sorry if this has already been answered but what is considered to be an imbalanced battery (x mV)?

 

[Candleflame]

Sorry if this has already been answered but what is considered to be an imbalanced battery (x mV)?

depends on the SOC. At low SOC its normal that the battery might have 20mV or so as not all cells get discharged equally, however, emptier cells with fill faster during charging. Full it really should be <5mv in a well balanced pack.

1mV is 0.001 Volts. To give you an idea 100% SOC is 4.2V, 90% 4.07V. So thats a difference of 0.13V for 10% SOC. So with 130mV imbalance you would lose around 10%. So even an empty battery sitting at 10-20mV imbalance isnt really anything serious...

 

[dhrivnak]

How long do you need to sit above 85% for the cells to balance, ballpark hours figure?

That has not been an easy question to anoswer. First we found out on the Roaster that balancing started at 83%. But while cells could be balanced at 83% (standard charge) as you climbed to 95% or higher, balancing would start anew. If you routinely charged to 85% then just a few hours would do it. But if the car sat in storage mode for a year or more then it could take a few days to balance.

For some reason Tesla changed the standard charge to 80% on the 3.0 packs and they would not balance unless you range charged. This did cause some issues. So every few months I made sure I ran the carge level to 90% or so and let the pack sit as I did see balancing at work.

The issue is there are two very real issues with lithium packs. One is there are always cell imbalances and you need to balance to keep the cells consistent or you will be limited to the weakest cell. You could BEGIN to see differences at 83% but the differences ere easy to see at 100%. Many people who only charge to 70% or less see a real and signficant loss in range after a year. But if they then charge to 100% for a few trips they normally see that range come back. That is balancing at work.

But charging to 100% is hard on the batteries and will also cause a loss in range. So we try to find that middle ground between the two very real problems.

 

[Bouba]

Does anyone know the difference between the the LG M48 and the LG M50 ?

 

[Steve446]

Does anyone know the difference between the the LG M48 and the LG M50 ?

See here for a top level view (en français): Batteries et autonomie à 100% des Model 3 LR / Performance - Forum et Blog Tesla
Sorry but I don't know if there's an English version of this. It mentions a constant of 137 Wh/Km for the E5CD version (M48).

 

[Sophias_dad]

I have a 2 kWh Bluetti battery pack that I use as the interface between my 700W solar panels and my car. The Bluetti lets me choose 50 Hz or 60 Hz output and the Tesla charger works with either one, so I thought I'd ask.

More deets if interested:

I currently charge from the Bluetti at 16A 120V. I start charging when the Bluetti gets near 100% charge - it allows both charge from my solar, and discharge to charge my Model 3 simultaneously. The Bluetti reaches full charge around 1:30 PM with a few hrs of good sun left. It charges my car at 1850W, and I can generally sustain ~600W input from solar throughout the charge, so the net wattage of the Bluetti throughout the charge is about -1250 W, and it is a 2kWh pack, which means with the press of one button a day (turning on the AC output of the Bluetti) I get approx 3 kWh daily right now. By the time the single charge cycle is complete, there is still some sun left, so I have to start the discharge of the Bluetti a little earlier each day. Which means I'm getting a little bit more than that 3kWh daily, as I have to start the discharge a little bit earlier each day to not let it reach 100%.

I expect towards summer I will be able to get closer to 3.5-4 kWh daily with this setup. It covers virtually all of my daily driving.

Since it is a limited setup, that is why I was curious about 50/60 Hz as I'm trying to pull as much as possible from the Bluetti, even if it is a small amount different

This really should have been a separate thread, btw.

60hz is likely imperceptibly more efficient, IMHO. Another almost equivalent question is whether the Bluetti is more efficient at >creating< 50hz or 60hz AC.

In the end, even a few percentage points difference, which is far more than imperceptible, is still nothing. Lets assume 4kwh daily, times 365, is 1460kwh per year, Multiply that by 2%, and you get 29.2kwh. At my very high local rates(0.29/kwh), that's $8 in savings. In reality, any benefits are likely 0.5% or significantly less than that, so <$2 per year.

 

[TrueTechData]

This really should have been a separate thread, btw.

60hz is likely imperceptibly more efficient, IMHO. Another almost equivalent question is whether the Bluetti is more efficient at >creating< 50hz or 60hz AC.

In the end, even a few percentage points difference, which is far more than imperceptible, is still nothing. Lets assume 4kwh daily, times 365, is 1460kwh per year, Multiply that by 2%, and you get 29.2kwh. At my very high local rates(0.29/kwh), that's $8 in savings. In reality, any benefits are likely 0.5% or significantly less than that, so <$2

I can make separate thread about it if you think people would be interested. My first thread was moved here by a mod so I just wasn't sure and decided to be safe and post here instead.

The setup isn't really about being cost effective to be honest, I won't ever make up the cost. And I know it is a small percentage and small effect, but I thought I'd ask since it is such an easy setting change. 30 kwh over a year for a setup that will last multiple years easily worth it since it takes me 20 seconds once to change the setting.

 

[Cincybearcatfa]

I've read several articles, studied graphs and watched more YouTube videos than I can recall but I'm wondering if any other M3 LR drivers can chime in on the difference in range when you drive 65 vs 85 or 90. Admittedly I have a VERY heavy foot. My previous car was a 2018 Cadillac ATS. It was 2 years old when I got it and it's average mpg was 30.1 when I started driving it. When I sold it to Vroom this week my average mpg was 23.1. When I drive, I drive. I take off fast, I stop fast and I pass pretty much everyone that I can. I drive 64 miles round trip to work everyday. From everything I've read I expect to get anywhere between 250-275 miles per charge driving like that. Can anyone who has experience driving like me share your experience? Thanks!

 

[LoudMusic]

This is going to be a good thread.

 

[Tam]

...drive 65 vs 85 or 90...

I think you can plug those speeds into the program but it may require paying a premium account so see the results of different speeds:

ABRP

ABetterRouteplanner is the world's most popular consumer EV routeplanner - both for beginner and experienced EV drivers. And of course for anyone curious about EVs.

abetterrouteplanner.com

 

[Big Earl]

I've read several articles, studied graphs and watched more YouTube videos than I can recall but I'm wondering if any other M3 LR drivers can chime in on the difference in range when you drive 65 vs 85 or 90. Admittedly I have a VERY heavy foot. My previous car was a 2018 Cadillac ATS. It was 2 years old when I got it and it's average mpg was 30.1 when I started driving it. When I sold it to Vroom this week my average mpg was 23.1. When I drive, I drive. I take off fast, I stop fast and I pass pretty much everyone that I can. I drive 64 miles round trip to work everyday. From everything I've read I expect to get anywhere between 250-275 miles per charge driving like that. Can anyone who has experience driving like me share your experience? Thanks!

More like 200 miles per charge in the summer and 150 in the winter.

 

[dfwatt]

I think you guys are missing the point. I'm well aware of the physics... my gripe is with the false advertisement. If I went to pick up the car and the sales rep told me, "Oh, by the way, that 300 miles of range you see there...that only applies if you drive 65 mph or less in a total vacuum. If you go even 75mph your range will be more like 190ish." I honestly might have walked away.

This should be told to the buyer up front. It's a misrepresentation at best, and a flat out lie at worst. In no universe its 75mph "fast", and the customer shouldn't have to do physics calculations. Obviously I know battery life depends on the driver's behavior... if you floor it at every stoplight, then I'd completely understand the decreased range, but we're talking about a very steady speed, all highway driving.

Blame the EPA'S testing methods not Tesla. My Lexus IS350 was rated at 28 miles per gallon on the highway, but wouldn't get that if you put a sail on it and threw it off a cliff. Well maybe if you went 45-55 miles an hour on the highway it would. So the discounting of range from what EPA says to a realistic Highway range and mileage is pretty similar across EVs and ICE vehicles

 

[beenmb]

Could be. Note that I said it didnt matter to the car, but I didnt say "it doesnt matter to the outlet". Most outlets are shared amongst other things. That outdoor outlet is likely shared among other devices at your home.

Outlets for car charging are supposed to be dedicated ones, but its very common for a home not to have dedicated outlets anywhere that you could normally plug in, or for those outlets to be dedicated for something else (like a dryer).

I think I would start with replacing the outlet, and making sure everything is torqued down properly on the outlet. "very warm" with electricity is a bad sign, and I would not want to trust a potential fire to "but I turned down the amps in the car to 8amps".

Yes I agree. I have been turning it down to 8A just to be safe. At 8A there is zero heat. Thank you.

 

[KenC]

I've read several articles, studied graphs and watched more YouTube videos than I can recall but I'm wondering if any other M3 LR drivers can chime in on the difference in range when you drive 65 vs 85 or 90. Admittedly I have a VERY heavy foot. My previous car was a 2018 Cadillac ATS. It was 2 years old when I got it and it's average mpg was 30.1 when I started driving it. When I sold it to Vroom this week my average mpg was 23.1. When I drive, I drive. I take off fast, I stop fast and I pass pretty much everyone that I can. I drive 64 miles round trip to work everyday. From everything I've read I expect to get anywhere between 250-275 miles per charge driving like that. Can anyone who has experience driving like me share your experience? Thanks!

Go to ABRP, abetterrouteplanner.com, and you can punch in your daily 64m commute. Change the speed, change the temp, etc. It uses real world data, so should be very accurate, as long as you give it good inputs.

 

[330volts]

The range of Model 3 SR+ is in question here. I live in SF Bay Area and past 6 months the range has dropped - 202 mikes at 90% charge and 223 mikes at 100% charge. Is this typical? The driving style is conservative - the average power consumption is around 200-250 Wh/mile.
Will appreciate if other owners can tell me what range is their car giving as it will serve as a validation. Thanks much!

 

[techzelle]

That "miles per charge" really needs to be clarified - because most likely you will not charge to 100% and definitely you won't drive to 0%.
You want the "realistic range" which is for a charge of around 90% to 25%.

Things shut down at 20%, like sentry mode, so I like to stay above that.

Any charge over 90%, if you do not drive right away and subsequently park with 90% and below, will get a pop-up message about: charging too high - may shorten your battery life, set your charge limit lower?...

I get "realistic range" of about 130 miles from 93% - 25% charge which equates to a theoretical 191 miles range for 100%-0%.
That is on Model 3 LR 19 inch wheels + boost, with sentry mode on, minimal AC / heating, no climate mode.

That is mostly short 5 -10mile drives, 80+ mph freeways, pretty aggressive acceleration.

Coincidentally, this was the same realistic range 125-130 miles, for a long freeway road trip, driving continuously, mostly cruising at 95-105mph.

Per spec, you'll get about 8-10% more range with 18" + aero vs the 19".

 

[Cincybearcatfa]

Thanks for the info. That’s exactly what I was wondering. I’m planning to drive my M3 to Englewood Florida from Cincinnati this summer. My sons are following in my wife’s VW Tiguan that goes almost 400 miles on a tank of gas. I’m guessing that we’ll have to add 2-3 hours to our trip for charging than if we were driving two ice cars.

 

[HenryT]

It's old info but still makes a lot of sense - take a look here. Tesla Range Information.