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I bought a CPO 992 a few months ago. It came with an aftermarket Anti Gravity lithium battery. I’m looking at OEM Porsche batteries since Anti Gravity says that their batteries are not compatible with 992s that were factory equipped with a Lithium ion battery. They were surprised to hear that my car was functioning fine with it, they were expecting a bunch of warning lights on the dash due to the battery management system not being present.
Here’s the question - based on the pictures, does my car look like it was factory equipped with an AGM or lithium battery? Lithium batteries have a secondary plug in the middle of the battery, and mine has that attached to one of the battery terminals instead…. Last picture is one that I found online.
Not my battery, but a picture of the additional plug I’m referencing. The ground harness also looks different.
With it being equipped with RAS and the sticker on the better strap, I’d say it came with a Lithium battery. Also, if it ain’t broke maybe don’t mess with it?
This is potentially good news for 992 owners with RAS. Would be breakthrough news if the cheaper AntiGravity Li battery could e substituted, with no ill effects. That said, bit surprised that AntiGravity, themselves, didn’t try, or know that this would work? Still a bit skeptical.
AG was surprised that the car wasn’t throwing any error lights on the dash. They also don’t think the 992 charging algorithm is suited to the AG battery or vice versa. I don’t drive the car much and have had two instances of the battery going completely flat and needing to use a jump box to get into the frunk. The handy part about the AG battery is that it has a jump start button built in, so the car fires right up once you get the frunk open. I’m going to start keeping the car on a Lithium compatible tender to see if that solves the issue.
AG was surprised that the car wasn’t throwing any error lights on the dash. They also don’t think the 992 charging algorithm is suited to the AG battery or vice versa. I don’t drive the car much and have had two instances of the battery going completely flat and needing to use a jump box to get into the frunk. The handy part about the AG battery is that it has a jump start button built in, so the car fires right up once you get the frunk open. I’m going to start keeping the car on a Lithium compatible tender to see if that solves the issue.
Well here is my official response... WOW THAT IS AWESOME! ACR89, do you mind if we reach out to you and get a few images more from you? This is very cool and great news.
I notice from the picture you provided that you actually have the Porsche "ground cable" from a NON-LITHIUM battery 992, and the reason this is so important is because the Porsche Lithium Version Batteries themselves have the Intelligent Battery Sensor (IBS) built into the battery, but on the 992s that do not have a Lithium Battery they have the IBS on the Ground Stap. This is important because the IBS is what puts out the data to the Cars ECU so it can know what the battery is doing. So we were wondering if the data would be reported any differently from the Lithium Battery's IBS, compared to a Ground Cable's IBS. But it would make sense that they would report data exactly in the same format so Porsche would not have to mess around with anything more than just putting a different Grounding Cable on the car and it would save a ton of time and money for them in production. So it appears the owner prior to you did this and it works. So the is the super cool thing.
A few months ago we bought one of those ground straps to see if we could swap out an Antigravity Battery into a 992 that came with the Porsche Lithium Battery and see if it would work. But we hadn't found a 992 owner who had the time to work with us on this. Then I got busy developing some new products and put it on the back burner. But this sort of proves our a theory we had that it should work, so we would love to talk to you a bit and get new pictures of the ground strap since it is cut-off in the images you had.
More details....
We are not worried about the 992 alogorithm, or charging profile not working with our batteries being we use the same interior Lithium cells and the same Lifepo4 battery chemistry. The thing that we thought might pose a problem was that the IBS in the Porsche Lithium would present the battery's data differently than the IBS on the Ground Strap, for example it might report the voltage in a different way or to diffferent nodes in the Linn System, and if it did , we theorized it could make the car throw flags. So we didn't want to tell people to try this and invest in a new Ground Strap and claim our Antigravity Battery will work. But your car is sort of the proof that it works.
But the cool part of this is I was reading your post and then I saw you picture you posted and noted that you have the 992 Battery Cable from a non-Lithium Batteried Car... though the image is clipped I could see it has the IBS on the Ground Cable, so that is why it is all working, and that is utterly fantastic news, and proving out that this works. Of course there are a few details I would like to know such as, did they just change out the Ground Strap, or did they also reprogram PIWIS? I assume you don't know the previous owner who did it but that is some basic info just so we have an idea of what they did. But in any event, I think this shows its as simple as changing out a ground strap. And if anybody else wants to try that we will work with you and give you a discount on the battery to try it in a few other cars to confirm everything.
Last things, I see you said you car is going dead and you don't drive much, so yes, please get a maintainer for the battery (lithium maintainer) because after our Antigravity Battery is drained to a point of dead it goes into sleep mode, but as you know with its built-in Jump Start it will start the car again easily, but it will be overdischarged when it starts the Car so you will have to drive about 2 hours to fully charge it , or simply put it on a charger over night..... BUT VERY IMPORTANT! I noticed you said "the car starts right up ONCE I GET THE FRUNK OPEN..." But the fact is you should NOT have to get the FRUNK OPEN before being able to use our "RE-START" Built-In Jump Starting. Our Batteries comes with two WIRELESS KEYFOBS, so you don't have to open the frunk first. Being you bought the Car used you may not have a Keyfobs, so reach out to me at the email (scott@antigravitybatteries.com) and we'll send you two keyfobs if you didn't get them with the car when you bought it. Also look in your glove box, the previous owner might have put one in there. That is where you want to put one so if you ever do get a dead battery you just press the keyfob and go, no need to get in the trunk.
Last edited by Antigravity; 07-03-2023 at 02:13 PM.
@Antigravity awesome, I was wondering why my ground strap looked different and why that plug was attached there versus the battery. I found this fob in my glovebox after buying the car but had no idea what it was for… is this fob for the battery? If so that’s a great feature and wish I’d known the last couple times I needed to jump start it!
feel free to PM and let me know what additional pictures you would like and I’ll be glad to provide.
Yes,that would be the fob to trigger the ReStart. You should see the indicator on the fob light up when you press the button as well as the red LED on the battery itself.
Best regards,
Last edited by Antigravity; 07-03-2023 at 02:41 PM.
Send me an email and we'll ship you and extra....
You can press the button on the keyfob and you will see the LED light ring around the button (the one located on the battery itself) will light up, that will show its working.
We will need your address to sent the Keyfob too... so make sure you include that and I will have the staff get that out.
After you evaluate everything, can you please post a final comment/report on whether you believe your AntiGravity battery will successfully work to replace the existing, OEM Porsche Li battery for the 992?
That would be fabulous if that is the case, provided it doesn’t start throwing error codes, etc.
After you evaluate everything, can you please post a final comment/report on whether you believe your AntiGravity battery will successfully work to replace the existing, OEM Porsche Li battery for the 992?
That would be fabulous if that is the case, provided it doesn’t start throwing error codes, etc.
Thx
For sure Cody, we just got a bit busy on some other things, and we just want to do one ourselves with a Customer so we can run a few additional tests, but it was hard finding a person to do this with us, we have posted a few time that we would work with someone willing to do this with us and give them a massive discount on the battery, and give them the Negative Ground Cable that we bought a few months back to do this test. It really won't require much of anything except a quick change of the Ground strap which is a 10 minutes to do, then hook up the battery and drive and see if any flags come up. The other thing we would like to do is see if it works fine in the AGM setting as well as the Lithium Settings in PIWIS. But since it probably in the lithium setting from the factory that should be a drop in and go scenario and no coding or registering the battery anyway. So it should be quite straight forward and simple and requiring no changes to the car at all.
We are in Gardena, CA about 20 minutes from LAX airport is anyone is around that area in L.A. and wants to test this with us.
The plot has thickened. I took my car to Porsche to investigate if it could have a parasitic drain, and when they looked up the build specs on my car, they found it originally came with an AGM battery, not lithium. That’s why I have that battery ground cable in my car. So since my antigravity battery will not hold a charge, I may just switch to an AGM battery versus doing another lithium.
For sure Cody, we just got a bit busy on some other things, and we just want to do one ourselves with a Customer so we can run a few additional tests, but it was hard finding a person to do this with us, we have posted a few time that we would work with someone willing to do this with us and give them a massive discount on the battery, and give them the Negative Ground Cable that we bought a few months back to do this test. It really won't require much of anything except a quick change of the Ground strap which is a 10 minutes to do, then hook up the battery and drive and see if any flags come up. The other thing we would like to do is see if it works fine in the AGM setting as well as the Lithium Settings in PIWIS. But since it probably in the lithium setting from the factory that should be a drop in and go scenario and no coding or registering the battery anyway. So it should be quite straight forward and simple and requiring no changes to the car at all.
We are in Gardena, CA about 20 minutes from LAX airport is anyone is around that area in L.A. and wants to test this with us.
Thanks, and totally understand. I have one of your products - the battery monitoring system. Great product.
The plot has thickened. I took my car to Porsche to investigate if it could have a parasitic drain, and when they looked up the build specs on my car, they found it originally came with an AGM battery, not lithium. That’s why I have that battery ground cable in my car. So since my antigravity battery will not hold a charge, I may just switch to an AGM battery versus doing another lithium.
I wonder if you can just code a car to use an AGM battery and be done with it? There option is certainly there in PIWIS:
I wonder if you can just code a car to use an AGM battery and be done with it? There option is certainly there in PIWIS:
i’ll ask Porsche when I pick up the car tomorrow. I really like the rear axle steering option and just want to make sure that it isn’t affected with AGM
07-02-2023, 08:00 AM
Battery type on early 992 with RAS
ACR89, do you mind if we reach out to you and get a few images more from you? This is very cool and great news.
