Tesla Model 3 buffer issues....

Kramer · 26-10-2022 8:30pm #1

This likely deserves a dedicated thread as it may also be an issue with LFP Model Ys too.

It seems like deliberately running the LFP pack cars to a low/very low SoC can reset the buffer. It's obviously not a bug, but a feature Tesla is using to protect the battery packs.

It's very questionable IMO as reducing the usable energy to 52kWhs on a new car could invalidate the WLTP figure attached to the car, when purchased.

Sure, the Tesla fans will chime in with:

it's for your own good.....it'll protect your battery
you can still use it, it's just hadden.....below zero......drive on & forget it
it's probably because it's cold.....normal...
it's probably a bug.....Elon will fix it in a future update.....

It's not a bug. It's purposely designed in to these Q3 cars. Why? Maybe the Q1/2 cars have shown excess degradation or some have been bricked due to excessive discharge/cold etc., & Tesla are on the hook for them?

Our 2x Model 3s, one from Q1, one from Q3. Both charged from a relatively low SoC (15% approx) to 100% overnight, last night.

The Q3 is not seeing much mileage yet so kept at around 50% SoC & charged to 100%, as per recommendations, periodically.

The Q1 has approx. 22k kms & started out at 62kWh gross capacity. It's now showing 59.7kWh (57kWh usable).

The Q3 now has an 8.63kWh buffer with 52kWh usable, yet still shows 430km "rated range".

If they lock away 12/15% of the capacity of the new "improved" Model Y with the 55kWh battery, owners could be left with 47/48kWh usable, in a bigger, less efficient car.

It'll be safer though (& much cheaper for Tesla to produce), so grand!

What if these buffers get locked at some point in the future?

Backwards Ted, we're going backwards!

Zurbaran · 26-10-2022 8:39pm

Don’t know how to quote between threads but I’m not worried about it sitting at zero if the buffer is so big. I don’t plan on letting it go down to zero again either if it does add the 6 or so %

reni10 · 26-10-2022 8:44pm

I tried the run it to 0% and let it sit overnight and it just sat at 0% so no difference in the buffer for me so it might work for some and not for others to increase the buffer so would be interested in what anyone else is seeing…

Zurbaran · 26-10-2022 8:47pm

https://www.boards.ie/discussion/comment/119797222#Comment_119797222

Might not work on later updates. Will post in here how I get on.

the_amazing_raisin · 26-10-2022 9:23pm

I know WLTP is a work of fiction but haven't Tesla always been taking liberties with the official range to the maximum?

I remember a quote from a while back where someone pointed out that it's basically impossible to achieve the EPA rated range on the US Teslas.

Tesla responded that the car calculates the buffers every time it starts based on ambient conditions so therefore if you can match the test conditions you can get the estimated range

Of course you can never match the test conditions, so you never get EPA range. Same goes for WLTP

So I don't think it'll have implications for WLTP because Tesla have already wriggled their way out of that argument

mc2022B2TF · 26-10-2022 10:04pm

I won't go over it again but the WLTP quoted for the mic 60kWh m3 is based off 57.5kWh usable. So the epa should be reduced accordingly if the usable is only 52kWh. I posted calculations on the main thread but the epa for a 52kWh usable is sub 400km.

Quoted range or wltp should never include having to run a battery past zero.

But the software is hardcoded with the 440km or so figure. If tesla were just transparent at least we would know but then they would be in trouble with the authorities for misrepresentation.

They sold something with a wltp rating assuming a smaller buffer but then realised the lfp did not behave as they may have expected. So they increased the buffer but as the battery pack was the same they couldn't re-do the wltp test so they just took a chance no one would really notice. It's a bkt mad.

It's plain wrong and dishonest and tesla know what they are at. Unfortunately I don't have the time nor resources to file a class action lawsuit against them 😔

Anyway my usable is now at 56kWh. Still less than the 57.5kWh that it should be but at least a lot better than the 52kWh it was until the trick of running to zero snd deep sleeping worked for me.

Jizique · 26-10-2022 10:06pm

https://www.boards.ie/discussion/2058269184/tesla-model-3-buffer-issues

Congrats, you've been musked

mc2022B2TF · 26-10-2022 10:11pm

Also worked for someone on the Facebook group from 6% the car woke up at 12%

Kramer · 26-10-2022 10:28pm

https://www.boards.ie/discussion/comment/119797172#Comment_119797172

CAUTION

If the Battery’s charge level falls to 0%, you must plug it in. If you leave it unplugged for an extended period, it may not be possible to charge or use Model 3 without jump starting or replacing the low voltage battery. Leaving Model 3 unplugged for an extended period can also result in permanent Battery damage.

Discharging the Battery to 0% may result in damage to vehicle components.

The car logs everything. Future issues may arise should you need to use the warranty.

If you allow the Battery to discharge to 0%, other components may become damaged or require replacement (for example, the low voltage battery). In these cases, you are responsible for repair and/or transporting expenses. Discharge-related expenses are not covered by the warranty or under the Roadside Assistance policy.

https://www.tesla.com/ownersmanual/model3/en_gb/GUID-7FE78D73-0A17-47C4-B21B-54F641FFAEF4.html

I reckon you could be in trouble should the low voltage battery (no longer a cheap lead acid) or even the HV battery have issues, down the line, if you regularly discharged to 0% or drove frequently beyond 0%.

I reckon the 60kWh cars were too close in range to the LR models & future Model 3s/Ys will have the smaller (cheaper) 55kWh pack so they are already sowing the seed by gradually reducing the capacity of existing cars.

All about cost reduction with Tesla. Drop the lumbar support, drop the radar, drop the parking sensors etc. Make the battery smaller & cheaper.....

Un-updated early 2022 cars could be more desirable in the coming years, still having working radar/sensors etc. & credible, usable 57kWh batteries.........or they'll all fail prematurely due to insufficient buffers 😀.

Kramer · 26-10-2022 10:31pm

Unfortunately I don't have the time nor resources to file a class action lawsuit against them

We don't have class action lawsuits here.

Small claims court...........judge, I demand Tesla pay me 5kWhs 😀

mc2022B2TF · 26-10-2022 10:39pm

https://www.boards.ie/discussion/comment/119797875#Comment_119797875

No chance the low voltage battery failing with an 8kWh buffer.

And the cars that have radar actually no longer have it since the move to tesla vision, it was effectively removed by software update.

Zurbaran · 26-10-2022 11:01pm

Also the new LFP batteries CATL are producing that are expected to be in newer teslas from December/January are more energy dense so should be better than the ones we are seeing now. The drop in size shouldn’t affect range and they will be lighter.

Not set in stone as Tesla don’t confirm these things but it is extremely likely.

Redfox25 · 26-10-2022 11:41pm

Came home recently at 10%, plugged up for a scheduled charge later that night. Few mins later car and app are saying battery was at 15%.

Made no difference to range predictions.

Kramer · 26-10-2022 11:59pm

And the cars that have radar actually no longer have it since the move to tesla vision, it was effectively removed by software update.

My Q1 '22 still has perfectly functioning front radar, no enforced auto-wipers or auto-lights when using AP (& a 57kWh battery (usable), with a stable 2.7kWh buffer 😀).

It's not acceptable for any manufacturer to alter a buffer to that extent & severely reduce usable range (to 0%), but here we are.

mc2022B2TF · 27-10-2022 12:30am

https://www.boards.ie/discussion/comment/119798235#Comment_119798235

What software version u running?

Zurbaran · 27-10-2022 12:42am

Just went out now as I need to charge for tomorrow and it went from 0 to 4%. So there was a gain but I don’t see it making much of a difference really.

Do I need to charge to full now? I ask because I do need a full charge tomorrow night for Friday where I will be doing over 300km without charging.

Zurbaran · 27-10-2022 12:50am

https://www.boards.ie/discussion/comment/119798170#Comment_119798170

Range prediction is set to the epa rating whether you have a car with the big buffer or one with a smaller one from earlier in the year.

Using the km range is terrible from my experience, the battery % is far more accurate and easier to understand.

Core6 · 27-10-2022 10:23am

I charged my Sept '22 M3 RWD to 100% last night.

When I looked at the figures on my scanmytesla this morning this is what it showed:-

Nominal Full Pack:- 60.1 kWh

Nominal Remaining:- 60.7 kWh

Energy Buffer:- 6.80 kWh

Full Pack When New:- 60.5 kWh

Usable Remaining:- 53.9 kWh

SOC:- 101% (although the screen was showing 100%)

Interestingly, the Energy Buffer value was 5.50 kWh when I looked a couple of weeks ago and 6.4 kWh two days ago.

mc2022B2TF · 27-10-2022 10:38am

https://www.boards.ie/discussion/comment/119798359#Comment_119798359

i dont think you need to fully charge - i cant remember what i did. I probably fully charged but i don't see it making a difference either way

zg3409 · 27-10-2022 8:58pm

I thought wltp was based on car range until it no longer moves, as in so low car shuts down totally, so below 0% displayed. Naturally all manufacturers try to get good numbers even if it's bad for the battery,

Other manufacturers claim 100% battery health on 5 year old cars, which if true means the extra buffer is reducing in size or else it's a simple lie. Warranty claims for battery degredation mean it's in manufacturers interests to tell users all is well, look no closer. Nissan has a great system of displaying degredation to drivers, yet dealers typically tell drivers batteries are 100%.

silver_sky · 27-10-2022 9:43pm

Original Renault Zoe 22kWh has a buffer above the advertised battery capacity. Mine is 7 years old showing 98% or about 22.8kWh available at full charge. The gross battery is almost 26kWh.

The thing with Tesla is that there is no advertised battery capacity, just range. How do you raise such an issue then?

Tesla Model 3 buffer issues....

Comments