How I Recovered Half of my Battery's Lost Capacity

[AAKEE]

I suppose, but even though I REALLY baby my battery, I don't even go that far. I just charge to 100% the night before using my normal start time. I suppose it does get done around 4 hours before departure, but I'm not so concerned about getting the timing right. It's not like I'm traveling very often.

Leaving it at 100% is not even near as bad as people think.
In many cases 100% is compareble with 80% and in some cases even better than 80%.

”Baby the battery” should be uding very low SOC. Charge late and never more than needed until next possible charging session. As 50% is the lowest setting this would be the best possible, except setting the charge to reach sufficiebt level when staring the drive, enabling for example the possibillity yo have the car sleeping at very low SOC and only let charge to the daily needed level like 20-30% or so.

This is the regular look of calendar aging research:
NCA is the thing to look after for LR/P in US.

And this is how it might look;
NCA, 2170:

 

[Jones1]

Good Info.

 

[Candleflame]

the principle reason to go to 90% rather than 100% is just that going to 90% doubles battery life (so its completely irrelevant to charge for your monthly long trip to 100%) and because if you charge without giving the battery a rest so voltage readings can be taken there is a chance you overcharge the battery to i.e. 103% which is obviously bad.

 

[scottf200]

the principle reason to go to 90% rather than 100% is just that going to 90% doubles battery life (so its completely irrelevant to charge for your monthly long trip to 100%) and because if you charge without giving the battery a rest so voltage readings can be taken there is a chance you overcharge the battery to i.e. 103% which is obviously bad.

Re: giving the battery a rest so voltage readings can be taken

So in theory, charging to 90% during the night before a roadtrip and start charging again to ~100 a couple hours before departure is a reasonable approach.

 

[AAKEE]

the principle reason to go to 90% rather than 100% is just that going to 90% doubles battery life (so its completely irrelevant to charge for your monthly long trip to 100%) and because if you charge without giving the battery a rest so voltage readings can be taken there is a chance you overcharge the battery to i.e. 103% which is obviously bad.

Yes, smaller cycles causes less wear, the the part that ”hurts” for the battery is the top part of the cycle.

 

[AAKEE]

Re: giving the battery a rest so voltage readings can be taken

So in theory, charging to 90% during the night before a roadtrip and start charging again to ~100 a couple hours before departure is a reasonable approach.

Thats not what @Candleflame says.

He is talking about the cyclic wear that comes from the cycling of the battery. Smaller cycles cause less wear. The top part of the cycle is worse, so charging to 90% instead Of 100% increase the battery life.



Calendar aging is the other part. And this is much less at 100% then most people think. This is because there are some myths established that live their own life. Look at post #821 above: The calendar aging is not much different at 100% compared to 90%.

My car is often parked at 30-40% overnight, sometimes 5-30% also.
I would not charge to 90% and then push the last part just before the drive, in that case you could charge to 100% in the first charge. The difference in degradation will not be measurable. Charging to 90% the night before and push the last part just before the drive is not bad -But it will not save you from degradation. So, I would not recommend you not to do that. You can do it, but it will not ”help”.

On the other hand, I do not charge to more than 55% daily, and I always charge late, so the whole charging session is short before the drive if I need more then 55%.

 

[**BatteryLow**]

I checked my Teslamate logger after charging my car to 31% last night. A lot of short sleep/wake cycles. Is this when the BMS is calibrating?

And the battery lost 3% from 31% to 28%. No sentry or other apps active. All usb and the 12v socket are not in use. Usable battery level will have gone to 23% with the battery getting cold. My garage is 10 celsius. My car is a 2020 model 3 SR+
at 116k kms and 335km range at 100% from 380km range when it was new.

 

[AlanSubie4Life]

I checked my Teslamate logger after charging my car to 30% last night. A lot of short sleep/wake cycles. Is this when the BMS is calibrating?

View attachment 901590

No the car should never do this. It’s just third-party apps or possibly a phone key itself messing with the car. Misconfigured in some way. Should never be hammering the contactors like this. I’ve seen it on my car: had to disable the app (changing password required of course - uninstalling the app does not break the connection of course), since there was no fix forthcoming from the developer.

Here’s a nice typical day assuming you did not drive the car much. Car plugged in (charge limit lower than SOC though); can see a drive in the middle of the day with Sentry Mode enabled.

I probably opened the car door at 11PM.

 

[**BatteryLow**]

I changed my Tesla account password last week and just my Teslamate logger got the new password.
How can a phone key be messing with the car?

 

[AAKEE]

I changed my Tesla account password last week and just my Teslamate logger got the new password.
How can a phone key be messing with the car?

You should start with “changing the password without giving it to Teslamate”.

Teslamate is our prime suspect for this, if you do not have other things installed .

With the new password Teslamate is out of the question and the car should sleep correctly. It that work out as planned, you need to find the settings in Teslamate that causes the many wakeups and change these to stop that. When done, teslamate should be able to be logged in without causing cobstant wakeups.

 

[**BatteryLow**]

how do you check the car is sleeping correctly without Teslamate?

 

[Flybyglass]

how do you check the car is sleeping correctly without Teslamate?

One way if plugged into charger see if the charger port indicator light is illuminated or dark. Dark asleep.

 

[Dave EV]

how do you check the car is sleeping correctly without Teslamate?

Just check the SOC after 8 hours or so and see if it's moved more than a percent or two.

Or go out and periodically check to see if you can hear the cooling pumps running.

 

[**BatteryLow**]

One way if plugged into charger see if the charger port indicator light is illuminated or dark. Dark asleep.

does it then sleep while charging?

 

[M109Rider]

does it then sleep while charging?

No. It can’t sleep while charging.

How long have you owned the car?
What is your odometer reading ?
How often do you supercharge?
What state of charge to you generally keep your car at ?

 

[Flybyglass]

does it then sleep while charging?

I have observed it wakes for charge then sleeps when complete.

 

[**BatteryLow**]

No. It can’t sleep while charging.

How long have you owned the car?
What is your odometer reading ?
How often do you supercharge?
What state of charge to you generally keep your car at ?

3 years,
116k kms,
10-20 times per year on holiday trips in summer and in winter
between 30% and 80%

 

[AlanSubie4Life]

how do you check the car is sleeping correctly without Teslamate?

You can either listen to the car periodically to make sure it is sleeping (very obvious based on noise), or you can get a cheap 12V battery monitor, since you have a 12V lead acid battery. Or you can monitor SOC and look at the new energy screen tabulation (which will tell you about excessive standby drain).

I am not blaming TeslaMate or a car key specifically. All I can tell you is that behavior is not normal (you should have heard frequent clunking, and half the time when you came out to listen to the car you would have heard it making noise). You should definitely change the password and leave it changed, to start with. It is a little tough to verify the behavior change without some way to monitor, but see above strategies. But first establish whether behavior you posted above is typical, look at what the car measures for losses in that state, understand the clunking and car noises, and get a full picture of the behavior (and be sure it is consistent and not a one-time thing).

Then disable TeslaMate and see if that all changes. If not, it is something else.

 

[**BatteryLow**]

You can either listen to the car periodically to make sure it is sleeping (very obvious based on noise), or you can get a cheap 12V battery monitor, since you have a 12V lead acid battery. Or you can monitor SOC and look at the new energy screen tabulation (which will tell you about excessive standby drain).

I am not blaming TeslaMate or a car key specifically. All I can tell you is that behavior is not normal (you should have heard frequent clunking, and half the time when you came out to listen to the car you would have heard it making noise). You should definitely change the password and leave it changed, to start with. It is a little tough to verify the behavior change without some way to monitor, but see above strategies. But first establish whether behavior you posted above is typical, look at what the car measures for losses in that state, understand the clunking and car noises, and get a full picture of the behavior (and be sure it is consistent and not a one-time thing).

Then disable TeslaMate and see if that all changes. If not, it is something else.

Thanks. I will start my investigation. Also my car is parked in an underground garage and maybe the cellular connection is not always present where my car is parked for charging. I can see my car in the Tesla app and I can use the app controls for charging etc when it is parked in this underground garage. But maybe the cellular connection is not stable and that is causing the Teslamate graph showing the many online/sleep cycles

 

[Flybyglass]

Thanks. I will start my investigation. Also my car is parked in an underground garage and maybe the cellular connection is not always present where my car is parked for charging. I can see my car in the Tesla app and I can use the app controls for charging etc when it is parked in this underground garage. But maybe the cellular connection is not stable and that is causing the Teslamate graph showing the many online/sleep cycles

Using the Tesla app will wake the car. Keep it closed until needed.