Surfingjeff

lithium battery is not a secret the best cells are Korean and Japanese Samsung or Panasonic several others ones . If you just break open the battery cover should be able to tell the key is the battery management system . You can find battery rebuilder can take any battery and repair it not worth taking to Porsche to get ripped off. The key is the ecu Circuit needs to be retained . I’ve bebuilt several e vehicles from scratch . 12 volt should be an easy one to repair .

Westikane

Lithium-ion batteries are where it's at for me. Recently, I decided to invest in an LFP battery pack from PKnergy for my outdoor adventures. Let me tell you, it's been a game-changer in terms of reliability and durability. Last camping trip, it powered my gear flawlessly for days on end. If you're in the market for a dependable power source, definitely give them a look!

Antigravity

IF you guys change the Ground Cable, you can use and aftermarket Battery either AGM or Antigravity Lithium. Porsche's Lithium Battery has its IBS (intelligent battery sensor) in the Porsche Lithium Battery itself, BUT for the AGM equipped Cars they have the IBS on the Ground Cable itself. So if you change out that Ground Cable then it still reports what it should to the ECU but it just you plug the connector into the Ground Strap rather than the Lithium Battery itself. Hope that makes sense. Screw driver it pointing to the part that you plug into when you change out the Ground Cable.

jlegelis

@Antigravity is that plug and play? Any PIWIS coding necessary?

CJDCREW

don’t have my car so maybe it would be more clear with it in hand, but I’m not following this post. I’m US market so despite getting a T will receive an AGM by all accounts, thus negating a good chunk of my weight savings in my car so I am planning to swap my AGM for your lithium immediately. Could you clarify what is needed in that case? I had thought from prior info that it was just remove AGM and insert antigravity lithium.

siberian

And how much weight are you thinking of saving vs. cost of LiFePO4??? As mentioned a gazillion times, the main issue with these batteries resides in the BMS; which is of course present in both AGM and lithium ones.

So though many folks have gone from lithium to AGM for FUD reasons (given underlying BMS issues), you must be the first one going the other way for reasons of "weight"? Thanks for clarifying...

siberian

CJDCREW

Approx 32 pounds difference between AGM and the porsche lithium per Porsche, right? I recall some debate on this in the past, perhaps it’s less? I’m presuming that the weight difference is about the same for the antigravity lithium vs Porsche. I’ve had great results with antigravity products generally and seems like it’s pretty cheap for the weight saved, if correct. Certainly a better ratio than the $3800 for @3 lbs reduction in my carbon fiber roof (which I know is a pretty dumb vanity choice!). I think I am in a rennlist minority (though not alone, as I’ve had convos on this topic offline) in being disappointed that Porsche advertised a group of features for weight reduction on the T and then pulled one that represented a very large component of the advertised weight reduction. I am aware of the frustration and problems people have had with the porsche lithium failing and the cost to replace and that Porsche has now stopped sending them to the US, probably lucky I won’t be getting that in truth but still annoyed at the weight difference. I don’t yet understand whether an AGM equipped car can easily swap in an antigravity lithium, which was the reason for my prior post. I had thought, from prior discussions and questions to antigravity, that a swap required nothing other than the new battery. If that is not the case it would possibly change my thinking. I do realize that it’s not unsprung weight and I’m not a good enough driver to tell the difference on a track let alone a public road and all the other points, I just like to do little things to my cars to make them mine and make them exactly what I want. This one I want to bend toward light with a few caveats (I had to have rear seats to please wife and wanted sofas because I’ve got a challenging back). I’m already pretty skinny so I’m not going on a diet! I’m happy to be educated and to have my mind changed, that’s one reason I love forums like this, but that has been my thinking.

siberian

As was mentioned, you need a new ground cable as well as the battery. HOWEVER, the underlying issues with the LiFePO4 is the BMS and that carries over to the AGM as well. OTOH the life expectancy of the lithium battery is supposed to be 10 years which is double the AGM.

Lastly and again I spent a lot of time researching this but there are issues with the ConBox as well (use the search tool) that may also point to latent issues. Best bet is to (when not driving it) place the car on a tender. Irrational, idiotic but there you have it. As to weight saving, I'm not tracking the car so I don't care.

siberian

CJDCREW

Thanks for this, as I have lurked around you always have good knowledge to share. I actually have tried to read on this topic, and had a dialogue with Antigravity as well. Your findings, and what I was understanding from the antigravity previous post, were divergent from the offline convo I had with them, so I grew confused. As I had mentioned, I do care about weight but understand many do not. Frankly, if I had known I would be getting AGM, I would not have specced RAS since it seems to require a larger AGM than would other wise be needed, increasing the weight difference. I AM very interested in the potential longer life of lithium also, Texas heat tends to chew up AGM batteries in my experience. However none of this would be worth a giant headache with programming or swapping parts/electronics and I do not want to mess with a tender. Had been hoping the Antigravity has figured out a magic bullet.

siberian

If you don't drive your car daily, I would seriously consider a CTEK tender. Battery drain from myriad of sources (especially PVTS) makes this a no brainer compared to the cost and pain of having a dead battery. Consider also disabling *** by running in SPORT Mode, yep, heat and cold will chew up batteries.

FWIW back in the day if you specced RAS you were forced to accept LiFePO4. Given the issues with it (again mostly centered on BMS and ConBox for selected years and software rev) they're now offering higher output AGMs.

siberian

CJDCREW

Disabling *** will be among the first things I do, I despise that innovation more than I do fire ants. I was aware of the change related to RAS and that drove the AGM switch with higher power and more weight, I mistakenly thought the issue was the battery manufacture vs the software and whatnot. Was hoping antigravity were superior and would be a good plan.

siberian

Though I have tried I've not yet managed to defeat *** permanently as was the case in 2020 and prior models where a button on the console permanently disabled it. Sport Mode is the only way AFAIK.

I'm not passing judgement on Antigravity and their batteries but simply stating that the issues run deeper and beyond their control.

GL

siberian

CJDCREW

*** - I’m planning to tune it so I think that will work to permanently get rid of it.

Understood on battery, I appreciate the knowledge share. Gracias!

Mike818

So I got my T and it came with the AGM.

I've been driving it around in normal mode during the break in to try and get first hand impressions of what I think about the start/stop system. I've been using a CC/CV power supply to recharge the battery after my drives, and It's pretty wild how depleted the battery gets just from normal driving. The way this car behaves with it's charging / battery strategy is not like any of my older vehicles. It seems like the strategy is to run down the battery and leave it in a depleted state.

So just based on that, I think it's probably beneficial to put the car on a tender even if you drive it daily. Even w/o Start stop it still doesn't seem to keep the battery topped up. At least not from my drives.

Larson E. Rapp

It will when you start switching to Sport mode full-time (which you should).