I think some forum members have used 40ah lithium batteries with no issues but those are H7 so slightly smaller. The 60ah is more than enough to power all the electronics and then some. I thought about the 80ah to power a dash cam and mifi unit for an extended period of time but decided it’s unnecessary.

At this point, I think if they had a 40ah H8 I would have gone for that because I think that’s all you really need. But I wouldn’t get the 40ah H7.

 

Thanks for the insight! Good to know as I was thinking of adding my old Blackvue dash cam set up. As I will not be needing it for extended time, 60 Ah looks to be perfect.

 

[size=13px]Datriani, [/size]

Thanks very much for posting the photos of your AntiGravity installation. I am getting ready to order the H8, 60ah as I think for my purposes and for the fact that it doesn’t get too cold here 60ah should be fine. However, was wondering if any coding needs to be done in order to notify the little black box somewhere that I have a new battery? Did you just drop yours in and that was it?

George

 

The car started perfectly fine for weeks without doing anything else to the car however I did do a battery reset using my OBDII reader because I saw it was an option. I honestly have no idea if it did anything or was necessary.

 

For those who have installed the Antigravity battery, have you noticed any adverse effects on performance? For example, car feels out of balance, less traction off the line (less weight over tires), etc. My OEM is starting to fail and I’m on the fence between this ($1,000) and an OEM replacement ($150-350).

 

Keep in mind the standard f-type battery is 90Ah and OP lost a third of their battery capacity with this installation. Might not be an issue, but with all the problems we see these cars have as the batteries degrade I'd be hesitant to go backwards. @jahummer can probably weigh in on this with an actual real-world anecdote.

You're not really going to notice much, the saving is about 0.8% of the car's weight so is equivalent to about a 4hp increase in a 500hp car. There's no bad weight saving, but some diets are worth paying for while others aren't and AG batteries in my opinion fall into the latter especially in a street car.

 

I am delighted with my AG 80 Ah battery. Going on over three years now and have never had a problem or issue with it. The fact that it has a remote, emergency backup, is of some piece of mind but I have never had to use it. I bought it on a Black Friday sale, saved about $200 , so to me with the significant weight saving, five year warranty, it was very much worth it.

 

Unless you’re building a dedicated track car there’s nothing sensible about replacing the OEM spec AGM. For an equivalent capacity LiFePO you’re going to spend 7X the cost of an AGM to save half the weight.

 

The weight savings appear to be ~50lbs (60 less 10), which is quite a bit in my mind but certainly not rotating mass (wheels are on the list after having just done VAP’s rotors). My question wasn’t on the practicality of it financially, it was on the AG’s impact on the car’s balance / weight distribution. Before pulling the trigger, I’m curious if anyone has noticed any adverse effects. If someone threw a 50lb bag of rocks in my trunk, I’d feel the difference driving. If someone takes AWAY 50lbs, what’s that feel like and is it always for the better.

 

The equivalent AG battery weighs 25.5 pounds…..

And for a front engine/rear drive the 14 pound loss in weight will have minimal effect on handling.

 

Thanks for the insight. And comparing 95ah to 95ah then I believe it’s 25.5, but I’ve heard the 95ah is overkill (especially if you have auto start/stop turned off). Reading through here it appears the 60ah is adequate, which weighs just over 10lbs.

 

I’ve got their 30Ah battery fitted. Weighs about 6 pounds and lasts 15 to 20 minutes with engine off. Keep it on a Ctek lithium maintainer. No issues at the track with needing to keep it charged.

 

Good to know, thanks. Are you happy with the feel of the 6lbs vs 60? I imagine you can feel it during braking and acceleration? I can notice the difference with and without a 100lb passenger.

The only glitch for me is that I’m in Denver where it regularly drops below freezing in the winter…the car is driven at least a couple times a week in the winter so I’m thinking the battery may need to be used only in the warmer months?

 

While I certainly respect your sense of sensible my sense is that the weight saved on my non-track car is very apparent. Notwithstanding the fact that the weight is being reduced on the driver side thereby giving my car a feeling of a better balance, the AG battery does have an emergency reserve which gives me a piece of mind. Is that worth the substantial extra cost. To me, yes it is. One can buy a Timex that tells time perfectly well or a Rolex that does the same. Is the cost differential important? Not to the person who buys a Rolex.

 

Had the largest stock size AG in my car. A week later car would not move, go, etc. Nothing wrong with the battery and car had been properly reset by the dealer.

Dealer said he had had about 4 similar issues with same batteries. No clear reason. My car is a 16. I did really want the thing too....dealer gave me an Interstate they had lying around free of charge as he felt bad for me...nice dealer. That interstate is now at 4 years and no issues. I got a bad taste from that for that battery in my car. No logic...but I followed all the rules, reset, etc. It did not work.

Recent super cold weather may have been an issue with the AG battery...under 0 at night and single digits in the day....car not in a garage....


PS: ON the form factor, saying you would do a 60A H8 but not an H7 may not be valid here as I suspect AG put the same stuff inside different sized boxes to allow the units to "fit" better. 60A is 60A internally...I'd be shocked (pun intended) if they had two different 60A solutions...would not make business sense.

 

Surely that’s understood! I believed the question to be about handling differences and my response was simply indicating any lack of benefit of doing this to a stock street car as the weight savings 14 pounds with an equivalent replacement will do nothing to handing or traction. He’s since clarified he wants the smaller battery. So yes with less weight over the rear wheels on a rear drive some traction may be lost. The AWD version would be different though.

 

Lithiums don’t like cold weather and yes 50+ pounds lost in the rear is slightly noticeable.

 

JCB,

Did you notify AG about your problem? Did they replace or refund you for the new battery that was faulty?

 

I fitted an AG H5 40Ah, which I picked up half-price nearly new from BMW write off track car. The form factor is considerably smaller than the H7/H8s that resemble the stock battery for size. There was plenty reach in the earth/pos cables to reach the terminals and the added bonus was that I was able to ditch the ridiculously heavy battery tray (~2kg) for a lightweight aluminium race tray. Carried out a battery reset (iCarsoft) and the AG has performed perfectly through two seasons including couple of below freezing winters. Holds 13.2v for weeks on end, but occasionaly gets a top up from the CTEK. My stock battery came in at 26.325kg v the AG at 7.165kg. Added to the 1.625 kg saved from battery tray and fixtures, managed to remove 20.785kg from car (45.82lbs). Pound/kg, it's by far the most cost effective weight loss on my car. Can't say I've noticed the difference in traction, braking or cornering, but kickdown/pickup in mid-range is noticeably sharper without the extra bag of cement in the boot. Not had to use the inbuilt 'Restart', jump start feature, but nice to have the back up just in case.

 

Thank you, sir! This just sold me. Seems I should definitely pick up the CTEK?