What SOC to keep tri-motor CT at?

Crissa

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It's not a matter of cost,
I hate to well, actually, to you, but the dynamic charging losses increase as the battery approaches 100%. Not only do chargers throttle down to keep the battery cool, they have to do cell balancing, and there are always losses in a charger: These are usually most extreme near the end of the charging cycle, as the voltage in the cells approaches the voltage of the charger.

It's a very small amount, but it would count, if you were measuring from the wall against miles driven.

But on the other hand, that cell balancing is healthy for the battery pack, and doing things like power battery management, pre-heat or pre-cooling, charging the aux battery, and powering the radios (for over the air updates) from the wall are things you probably don't want to do from the traction battery.

-Crissa
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Rthardison

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Standard 80%
 

Halemarine

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Correct me if I'm wrong, but I got the impression from a battery management video that Tesla cars have a built in management system based on your average daily miles. Is that true?

Also, does it actually add that much to let it boost up that last 20% before a road trip?
I traveled in my wife's Model Y between Ft Lauderdale and Richmond Virginia for two months this winter.
Mostly charging from 10% to 80% at Tesla Super Chargers. Times ranged from 25 to 30 minutes. On the last leg of the 18 hour trip I would charge from 10% to 95% in about 50 minutes (nap time lol). Going up to 95% or 100% does extra time, roughly twenty to thirty minutes depending other factors, like temperature, other vehicles charging and speed of the charger.
Hope this gives some insight about time
 

Owner13669

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Install ABRP (a better route planner) on your phone. You can choose the cybertruck as your vehicle, and experiment. It will plan a trip for the minimum time charging. For instance from my home to Orlando Florida, never going below 20% or above 80%, would take 8 charging stops, averaging about 30 minutes each. If you spent a night in the hotel during that 25 hour drive, you would charge to 95 or 100%, and adjust the plan after that. If you adjusted to supercharging to 100%, there would be fewer stops, but much more time charging.
 

ldjessee

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My thought at this time is to keep it at 50-70% unless planned trip.

I have a reservation for the Dual Motor.
 

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These will be lithium-ion. The closer to 50% you can keep it, the further from 0% and 100%, the better.

Shallow charging and away from uneven heating is best for cycle life.

-Crissa
What is "shallow charging"?
I have a 2017 Ioniq that I just charge at home on a Level 1 (110V) regular wall adaptor (dedicated circuit of course!). But I have had periods (ie: pre-covid) where I was charging using a fast charge Level 3 on a weekly basis - sometimes two or three times/week. I have seen virtually no drop in range or performance and have over 80,000km logged so far (50,000miles). Should I expect some massive drop off in range suddenly due to my fast charge uses? Have Tesla owners had issues with range dropping significantly with overusing fast charging?
 

happy intruder

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my 2019 model 3 has a range now of 288 miles...we charge at home on a Tesla HPWC...wife charges to 90%.....should we be charging to only 80%.....also, what are the steps in balancing out the battery......I am so confused ......thanks for the help
 

Delusional

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To extend battery lifetime, it is very simple.
Keep the cells in their comfort zone at all times.

Do not stretch them in either charge or discharge direction.
High heat plays a role when fully charged.
Cold can also be a problem, but only if over-discharged.

For super-long lifetime you want to keep the batteries as "comfortable" as possible, meaning leave them as near to the middle of their capacity as possible. Never deviating outside of forty and sixty percent capacity would be ideal to extend the overall lifetime of the cells. There should be very little cell degradation if you adhere to this, even over thousands of cycles.

Recent research has proven that leaving most types of lithium cells at full charge AND in high heat can degrade them. This is when the electro-chemical reactions are in their most active state. I would say that the hotter your ambient temperature, the less likely I would be to 100% charge the cells. However, if I plan on immediately using the full-charge's capacity, I would trust the vehicle's cooling system to mitigate this factor.

Over-discharging is another way to degrade the cells. It's going to have to be an emergency of the highest degree to get me to use my vehicle below ten percent charge. Once voltage inside a cell gets too low, it can be difficult to recharge it. The proper way to recover an over discharged cell is to warm it up and a trickle charge until they are back in their comfort zone. Then they "should" be back to normal, but I don't know how Tesla handles this situation. Maybe some cells don't come back at all leading to difficulties with cell balancing after an over-discharge event?

Cold temperatures have been shown to NOT cause lifetime degradation to lithium cells, however, if your battery is very low, and then the cells get super-cold, voltage inside the cells will drop, possibly too low. If you're in a cold climate, don't park it for a week unless charge is over 20 percent.
The proper way to long-term-store lithium cells is to get them between 40 and 60 percent charge, then put them in a n airtight container and into a refrigerator. (not a freezer)

The quickest way to degrade your battery is to overcharge it. (until it catches fire) With a properly functioning charger, this should be impossible.
One of the things that make the iron chemistries safer is because once they are full, it becomes very difficult to force additional charge into the cell. They simply won't accept an overcharge.
 

EV Rob

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From all I've read, D is right. We charge my wife's Model S to 75% every night, balancing battery comfort against apocalypse readiness, as we live in earthquake and fire country.

We charge to 95% the night before infrequent long trips, never on a supercharger. Then before AM departure we add the final 5%, which prewarms the battery while minimizing duration at full charge. Anticipate doing the same with my CT3 unless its battery comes with different recommendations.

BTW - wish Elon would offer a CT 2.5 - dual motor with 500 mile battery. Don't need the speed or power of the CT3 -just the range of the CT3 and AWD of the 2.
 

Wood Wombat

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Lots of talk about battery longevity, but nothing about performance. So, to add to the conversation I have a Model 3 Performance and I notice that maximum acceleration is only achieved at over 80% SOC, with 90-100% being very savage indeed. Based on the typical voltage curves for these batteries, I would be surprised it the CT was any different.

That said, I still charge to 80% and rarely drop below 20% unless I am on a long trip, and then only for short periods outside that range.
 

Delusional

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If you are really interested in this topic, battery university dot com is where you should start.
I will quote one line of the article. "The worst situation is keeping a fully charged battery at elevated temperatures."
how_to_prolong_lithium_based_batteries-BatteryUniversity
I will quote one line of the article.
"The worst situation is keeping a fully charged battery at elevated temperatures."

Another place where I have learned a lot is candlepowerforums
Batteries and Electronics. Candlepowerforums



The following sounds like BS because I've lost the link and can't produce the evidence, but...
I think it was 2016 when I read about an "informal" study done somewhere in Northern Europe.
They ran various charge profiles and temperatures on various battery chemistries.
The one that stood out was nickel-cobalt lithium type cells that were cycled from 40% to 60%. They stopped the test at 30,000 cycles with the cells still at over 90 percent capacity.
 

Delusional

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As for WoodWombat's statements about (vehicle) performance at battery state-of-charge (SOC), well, ....duh.

Each and every cell in the battery pack is charged to "full" when it's voltage is 4.2V. ( I assume that Tesla uses this standard voltage as it's cutoff point.) As soon as you start driving, that voltage begins to drop, and it's simple math. Volts times Amps equals Acceleration. This is another advantage of moving to a larger cell format. They should be able to handle larger amperage draws,

If you wanted to, and the charger would allow it, you could charge your cells to a higher voltage than 4.2V, and get even higher performance.
 

Diehard

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i would love to have something greater than the CT1 because it gives more room in that happy zone.
for my thought process... ct3 500 miles range. so 400 is 80% , 100 is 20% which leaves 300 miles range
while ct1 300 range 80% is 240 20% is 60. so 180 range
for longer battery life

but for me that would be perfectly adequate
Also a CT3 that does 20-80 carries more dead weight than a CT1 that does 20-80, provided battery chemistry remains the same. If it improves and we can all use the 100% without penalty, It is a win for all of us regardless of the trim and win for Tesla because they don't have to put as much battery in their vehicles. Their estimated range would be more realistic too.
 

Crissa

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The following sounds like BS because I've lost the link and can't produce the evidence, but...
I think it was 2016 when I read about an "informal" study done somewhere in Northern Europe.
They ran various charge profiles and temperatures on various battery chemistries.
The one that stood out was nickel-cobalt lithium type cells that were cycled from 40% to 60%. They stopped the test at 30,000 cycles with the cells still at over 90 percent capacity.
No, I saw that one, too!

-Crissa
 
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