90% the new recommended SOC?

[Knightshade]

Well, they either think it is important or they are trying to reduce their liability. Telling people to plug in reduces the likelihood that someone messes up and runs out of electrons but is not necessarily the best solution for long term battery health.

.... what? That's exactly backward.

What liability, specifically, do you think attaches if an EV owner runs out of fuel by not paying attention?

Why would you think it's any more a "liability" than someone running out of gas in an ICE vehicle?

On the other hand recommending what to do to the car that's bad for its long term health could cause actual liability to the car company.

 

[Shock-On-T]

.... what? That's exactly backward.

What liability, specifically, do you think attaches if an EV owner runs out of fuel by not paying attention?

Why would you think it's any more a "liability" than someone running out of gas in an ICE vehicle?

On the other hand recommending what to do to the car that's bad for its long term health could cause actual liability to the car company.

Running the battery dead flat and leaving it that way will catastrophically damage the battery.
That is the liability Tesla avoids by recommending keeping the car plugged in.
This is the only think an owner can do to seriously damage the battery. Charging even to 100% every days is far less serious.

 

[TexasEV]

Running the battery dead flat and leaving it that way will catastrophically damage the battery.
That is the liability Tesla avoids by recommending keeping the car plugged in.
This is the only think an owner can do to seriously damage the battery. Charging even to 100% every days is far less serious.

Not since the Roadster.

 

[Knightshade]

Running the battery dead flat and leaving it that way will catastrophically damage the battery.

It's also physically impossible- so your idea continues to make no sense.

The car will shut down before you get to that point.

 

[Shock-On-T]

It's also physically impossible- so your idea continues to make no sense.

The car will shut down before you get to that point.

Unfortunately, my strident friend, the battery continues to discharge even after the BMS shuts it down.

 

[Shock-On-T]

Not since the Roadster.

The over-discharge cutoff voltage may be higher since the roadster, but that just gives more time before the battery self-discharges to a dangerously low level.
Nothing can stop batteries self-discharging.

 

[Shock-On-T]

So much hand-wringing over such a simple topic. Short version:
- best for battery is 50% SOC
- best for driver is 100% SOC
- best compromise is somewhere between those values

Good news is the differences are very small unless you get very close to 100%, so do what you like.

 

[JRP3]

The over-discharge cutoff voltage may be higher since the roadster, but that just gives more time before the battery self-discharges to a dangerously low level.
Nothing can stop batteries self-discharging.

Actually cells have almost zero self discharge, it's the BMS which draws power. If the pack gets down to a low enough state the BMS should disconnect to preserve the pack. I have bare lithium cells close to ten years old still holding a charge.

 

[Whisky]

This dispute over whether to charge routinely to 80 or 90% reminds me of Henry Kissinger’s quote that academic politics are so vicious because the stakes are so small.

The reason for the debate is because the difference in outcome is so small. If there was a big difference, it would have been obvious long before now and most everyone would agree on what’s right.

Awesome observation!

 

[derotam]

I am confused regarding shallow charging. Some people say shallow charging is good so you should plug it in whenever possible but some say you need deeper charge so not to confuse the system?

Shallow charging doesn't hurt the battery. It may confuse the system's idea of what the capacity of the battery is, but it doesn't hurt the battery.

 

[Knightshade]

The over-discharge cutoff voltage may be higher since the roadster, but that just gives more time before the battery self-discharges to a dangerously low level.
Nothing can stop batteries self-discharging.

I admire the tenacity with which you continue to be factually wrong about this.

Meanwhile back in reality your argument has become "Best for driver to hurt battery life by charging to 100% every time as it makes it slightly less likely he by accident runs the car to 0 and then let's it sit for years without plugging it back in again, because ShockOnT has no understanding of how the post-roadster BMS works or what "liability" legally means"

 

[derotam]

Actually cells have almost zero self discharge, it's the BMS which draws power. If the pack gets down to a low enough state the BMS should disconnect to preserve the pack. I have bare lithium cells close to ten years old still holding a charge.

Yeah, and I have lithium batteries that are 20 years old still holding a charge, and rechargeable lithium ion batteries that are 5 years old that are dead. Chemistry makes a difference, as does storage temperature. Li-Ion's don't like cold temps.

 

[Whisky]

I normally don’t charge daily, instead I wait to battery is around 20%, then I charge to 80%. Looks like I need to change my habits. Comments??

Daily charging is best, or at the very least, having the car plugged in daily. You can see the long string of debates between 80% and 90%, but charging daily to that range is best.

 

[Whisky]

FWIW, during the Toronto TM3 delivery event they sent a senior Tesla technician, and the recommendation from her was to always charge to 90% unless you need more for a road trip.

There's been a number of reports with depleted displayed range with TM3 owners that charge to 70% daily, though doesn't seem to happen to everyone (for whatever reason, I don't know). I was surprised that the depleted range, while temporary, is accurate for that charging state (so if it says 280miles on a full charge, you're only going to get 280 EPA rated miles from that charge).

With the exception of the above mentioned potential issue, is really doesn't seem to matter whether you charge to 50% or to 90% daily, so long as you take basic care of your battery such as plugging it in daily, and not doing daily 100% chargers, and not constantly discharging it down below 5%.

There's no reason to stress about this, just enjoy your car!

 

[JRP3]

Yeah, and I have lithium batteries that are 20 years old still holding a charge, and rechargeable lithium ion batteries that are 5 years old that are dead. Chemistry makes a difference, as does storage temperature. Li-Ion's don't like cold temps.

I was of course talking about rechargeable lithium ion cells since that is the topic at hand. For long term storage lithium ion cells do like cold temps, they don't like being charged below freezing though.

 

[Santa Claws]

I've been charging daily to 90% because P3D

And when I'm ~15 minutes away from driving, I'll open the app and move the marker to charge to 100%. That ensures me a warm battery.

 

[tga]

I’m going to throw wrench in here because its the internet haha...
The more cycles a battery experiences the shorter the battery life.

Yes, but a "cycle" is 0%->100%->0%. 70%->80%->70% is 1/10th of a cycle.

 

[tga]

A while back, Elon said 30-80 is better than 40-90 - Elon Musk on Twitter

 

[voip-ninja]

I just wanted to bump this as it's a pretty important topic and hasn't had much (any) discussion.

 

[ℬête Noire]

I can't stand that chick but the video was quite informative.

If what she's saying is correct then Tesla needs to modify the software so that 90% no longer shows "trip" in the charging screen.

It doesn't list 90% as Trip. It brackets above 90% as "Trip", below 90% is bracketed as "Daily". This is not a change from that. Normally charge to 90%, at least once/month go to 100% (whether for a trip or just to send it through it's balancing cycle). Ironically the prior advisory was to disregard the Model 3 UI.

EDIT: Personally I'll probably still leave the top end of my everyday charge at about 85%, where it won't impinge on my regen ability. Above 85%, depending on ambient temp, and you start getting dots on the left of your regen/acel bar. Roughly 260mi easily covers my usage. Reason is that I live in a relatively hot region, and the effect of heat is multiplier of any degradation due to high charge.