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Model 3 12v Battery issues, monitoring, Aftermarket replacement

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Umm, you don't run sentry mode when you're away from the house?
Irrelevant. You introduced this irrelevancy as a way of discrediting the notion that batteries with less internal loss offer any advantage. Stick to the original question. Stop introducing irrelevancies. See under questionable debating tactics the definition for knocking down straw men. Actually don't bother.
 
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Umm, you don't run sentry mode when you're away from the house?
I do at local short stops but when at the airport for 4-6 day business trip……NO. A one mile per hour drain over 4-6 days? In winter….with winter degradation and vampire drain…no thank you. I’d like to but the hit is too much….sometimes it would preclude me from making my almost 100 mi drive home.

Ski
 
Irrelevant. You introduced this irrelevancy as a way of discrediting the notion that batteries with less internal loss offer any advantage. Stick to the original question. Stop introducing irrelevancies. See under questionable debating tactics the definition for knocking down straw men. Actually don't bother.
And you conflated self-discharge with phantom drain.......... when the two are not related.

Repeat after me. 20wh/week is NOTHING. You lose 3 miles per year due to using a 12V lead acid battery.
 
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And you conflated self-discharge with phantom drain.......... when the two are not related.

Repeat after me. 20wh/week is NOTHING. You lose 3 miles per year due to using a 12V lead acid battery.
As someone once said your analysis is not even wrong. You forgot to include the inefficiency of charging of lead acid batteries which is many times over that of lithium ferric phosphate. There's a roughly 10-12% greater charging loss for lead acid chemistry compared to the charging loss for lithium iron phosphate. That's a differential of essentially 10 to 12% for every single wh that comes out of the 12-volt system. That's actually a lot. Way more than your wildly optimistic number.

Please come armed with facts and not optimistic suppositions and assumptions. Do your homework. Read up on the white papers comparing these different chemistries then come back with some facts. Otherwise don't bother. I guess Tesla didn't get your memo that lead acid was really better than lithium ion or at least at the differences were negligible suggesting that their recent conversion of the low voltage system to lithium iron phosphate was ill-advised. Perhaps you know something that Tesla does not. Then again that seems unlikely doesn't it? Especially since you didn't even know about the differential charging loss between the chemistry's.
 
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Glad that you put in those last two words open quotes for myself close quotes. Because the prior post made it sound as though you were talking about what was best for everybody.
Okay, but can you explain what the advantages YOU listed are so special for YOU? I am still not seeing a compelling argument for the battery and I am trying to understand it
  • "~20 lb weight loss," - How does a one half of one percent weight savings really get you? I mean, it is an advantage, but it sounds pretty superfluous
  • "better subwoofer performance due to to better Peak power output," - According to whom and what facts? Is it a relevant fact or just a gratuitous selling point?
  • "10 yr service life..." - What is the cost/savings benefit to this? As I mentioned in my previous post, I could buy three standard batteries in that time frame and still come out ahead dollars wise (okay, maybe break-even once one accounts for inflation)
  • "...significantly less Phantom drain." I think "significantly" is more hyperbole and would love to see that math on what this really is. Am I spending a couple dollars more per year to charge or several hundred?
  • "And then there is Ohmmu's phenomenal service." - What do you need service on? Either a battery is dead or alive. If I am unexpectedly hit with a dead battery, I almost always can get a replacement (whether thru Tesla, Costco a local auto-parts store, or a myriad of other sources) within an hour or two.
  • "On par with mountain pass performance." - On par for what?
 
I do for a very specific reason: due to a recent firmware update, it is the only way I can get the car to remember where my playback position is on my USB music. A REALLY stupid approach (and thankfully I don't have to pay for charging), but it is MY reason.
Really? I didn't think there could be any more reasons not to use USB audio, but here comes a new one. I gave up on USB music fairly quickly due to the many deficiencies. Fortunately, my hearing is less than ideal anyway (too many loud concerts in my younger days and too long since my younger days), so bluetooth sounds OK and my phone has ample storage.
 
Really? I didn't think there could be any more reasons not to use USB audio, but here comes a new one. I gave up on USB music fairly quickly due to the many deficiencies. Fortunately, my hearing is less than ideal anyway (too many loud concerts in my younger days and too long since my younger days), so bluetooth sounds OK and my phone has ample storage.
The only way to hear lossless music in a Tesla is via USB music. The compression of streaming and BT is terrible (to me) - I can definitely hear the difference (especially since I had installed a pretty high-end aftermarket sound system). Music quality is very important to me and it is exceptionally rare that I am not listening to anything that isn't from a USB drive (the only time music isn't listened to that way is when I update the Samsung T5 and it needs to re-index (which at 13K+ tracks, takes a while).

I know this isn't for everyone, but I also know I am not alone in this preferfence.
 
The only way to hear lossless music in a Tesla is via USB music. The compression of streaming and BT is terrible (to me) - I can definitely hear the difference (especially since I had installed a pretty high-end aftermarket sound system). Music quality is very important to me and it is exceptionally rare that I am not listening to anything that isn't from a USB drive (the only time music isn't listened to that way is when I update the Samsung T5 and it needs to re-index (which at 13K+ tracks, takes a while).

I know this isn't for everyone, but I also know I am not alone in this preferfence.
Oh, I understand... in my younger days, I didn't even have a TV, just a stereo system with all separate components: large amp, preamp, tuner, turntable. My boss at Dolby Labs had a turntable that costed about $1500 with separate tonearm, turntable, cartridge, stylus. There were some fanatics there who didn't think much of CDs when they came out.

I was complaining about Tesla's lack of USB support that makes it so difficult to use. But for me now, it's not worth going to the trouble of adapting to using it. Also, due to road noise and traffic, the noise level is fairly high, which would require a pretty loud volume to get a decent dynamic range, and I don't really think it's a good idea to play really loud music while driving. So if I want the best sound, I wait until I'm at home with a better system. And nowadays, I don't know if I can tell the difference between BT and wired music; it's not that easy to compare, though.
 
The only way to hear lossless music in a Tesla is via USB music. The compression of streaming and BT is terrible (to me) - I can definitely hear the difference (especially since I had installed a pretty high-end aftermarket sound system). Music quality is very important to me and it is exceptionally rare that I am not listening to anything that isn't from a USB drive (the only time music isn't listened to that way is when I update the Samsung T5 and it needs to re-index (which at 13K+ tracks, takes a while).

I know this isn't for everyone, but I also know I am not alone in this preferfence.
Curious what you did to the Audio system?
 
I was complaining about Tesla's lack of USB support that makes it so difficult to use.
This I cannot disagree with - it is absolutely atrocious

Also, due to road noise and traffic, the noise level is fairly high, which would require a pretty loud volume to get a decent dynamic range, and I don't really think it's a good idea to play really loud music while driving. So if I want the best sound, I wait until I'm at home with a better system. And nowadays, I don't know if I can tell the difference between BT and wired music; it's not that easy to compare, though.
My ~30 minute commute each morning and evening (mostly the latter) is my sanctuary. I let AP (and NoAP for a couple of transitions) take care of the driving so I can just enjoy my music. I know that a car is not an ideal listening environment, but with the exception of one stretch of freeway flyover, it isn't too bad. Having a very solid system to help drown out the world is my release and is quality "me" time.

I've had home systems and have good cans (headphones), but to be able to fully enjoy, I would need down time of doing nothing, and that is a luxury I don't have very often.
 
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Curious what you did to the Audio system?
It is mentioned in my signature, but I had the guys at Reus Audio install their stage 2.5 system. These guys have been around for a while and actually design and have custom-built their own amps, drivers, and x-overs. If you were local, I would invite you to meet me and take a listen: the difference is amazing. While they are Southern-California based, Clifford travels the country doing installs. They aren't for everyone (they are a bit spendy), but if you appreciate better sound, it is worth the money.
 
You can buy a group size 51R battery from any place that sells car batteries and that will fit and work on Model 3.
It has to be lead-acid (so no AGMs, etc), correct? I read that Tesla is the cheapest alternative. Is that still the case? My car is hitting at 1.5 years old. Is that still a good idea to replace every 2 years, or until we actually get the warning from the dash? Thank you.
 
It has to be lead-acid (so no AGMs, etc), correct? I read that Tesla is the cheapest alternative. Is that still the case? My car is hitting at 1.5 years old. Is that still a good idea to replace every 2 years, or until we actually get the warning from the dash? Thank you.
As someone once said if it ain't broke don't fix it. Your battery could last for 4 years.
 
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Awesome. Thank you very much. And now that we won't use the car to travel, I can definitely wait until I get the dash notification, and just buy a new battery then, and install it myself. Need to find where the heck I stored the instructions to do that. I vaguely remember having to lower the windows, power down the screen, disconnect the contactor below the rear seat, then replace the battery (then those steps in reverse), but need to check that the order is correct. Ha ha. Or that I didn't miss a step, like first disconnect the negative battery wire at some point. Thanks again.
 
It has to be lead-acid (so no AGMs, etc), correct? I read that Tesla is the cheapest alternative. Is that still the case? My car is hitting at 1.5 years old. Is that still a good idea to replace every 2 years, or until we actually get the warning from the dash? Thank you.
Funny you should ask...

This morning, I got the dreaded messages that my 12V was having issues. I tried to get a service visit from the truck to replace but the soonest appointment was Saturday. From all I have read here, I knew to get it taken care of immediately.

I drove my car to the Irvine Service Center which is 2 miles from my office (which in the city of Irvine means a 15 minute drive because of the ridiculously long signals). I would have just purchased and put in myself (somehow) but they said they could do it there and threw me some Uber credit.

I should note that I was 149 miles out of warranty (50,149 miles) but they fudged it and got it covered BUT the quote I remember (before they adjusted) was $126 and change.

I've had my car for 32 months and as mentioned, right at 50K miles. I have heard many people whose batteries failed around the same timeframe (even with fewer miles). And from what I have read from many on here, once it gives you the warning, you need to replace immediately (like, tomorrow is too late). Thankfully I live and work in an urban area with easy access to a replacement, but if I were more remote, I would consider other options.
 
It has to be lead-acid (so no AGMs, etc), correct? I read that Tesla is the cheapest alternative. Is that still the case? My car is hitting at 1.5 years old. Is that still a good idea to replace every 2 years, or until we actually get the warning from the dash? Thank you.
An AGM is a lead acid battery, with slightly different charging characteristics. For the most part, it shouldn't make a difference whether the battery is AGM or not. But an AGM battery will cost more than not. I would replace my battery with an AGM because it will have the port to connect the hose to vent any gases under the car.

The Tesla OEM battery will be the cheapest battery at $85 (slightly higher if you want then to install it for you). I would only replace the battery once I get the warning or it dies because it's easy for me to jump start my car and I can buy a replacement battery anywhere.