TwinTurbo420

I do not need it yet but, want to know my aftermarket choices when I need to replace my battery.
2019 C2S
From my battery label:
80Ah 800 A EN Banner 999.611.080.12

I see on Porsche parts sites that in addition to the 80Ah 999.611.080.12
They also have:
95 Ah 999-611-095-12 (more power & more weight?)
70 Ah (Didn't copy the part # since would not replace with lesser power battery)

I cannot find other specs online. Especially size. I’ve read old threads for older versions & one guy used a larger NAPA battery that weighed 58 #!
I think it was size 49 (which is H8) 92Ah, 850 CCA

https://www.napaonline.com/en/p/NBP9...dInput=battery

So, is my OEM battery size H6?
One poster said he needed AGM MTX H6 Interstate Battery

What aftermarket brands have people found in the U.S.?

I know it is best to register the new battery & I think this can be done with Autel MD808 Pro.
I know it is best to keep the 12V power supplied during the swap & I can do that with my jump starter JNC 770 per the manual.

Bob Z.

https://rennlist.com/forums/991/9605...ry-y-or-n.html

https://rennlist.com/forums/991/1041...ement-diy.html

https://rennlist.com/forums/991/1170...batteries.html

etc

TwinTurbo420

Thanks Bob!
I had read the 1st link b4 posting. Post #12 is the NAPA battery I mentioned. Post #25 mentions the Interstate MXT H6 I mentioned. Not at all a definitive answer. I looked up NAPA on my own to find the specs. From this thread it appears as if the 991 can take either a H6 or an H8 size?

2nd link, I had also read. How to replace the battery, so I skimmed it a few pages. But I did not click on the link for the Duracell until just now.
Duracell Group 49 (the big one like that NAPA one.)
The OEM battery in that post is different than my OEM. Less capacity. Probably changed from 991.1 to 991.2?
I still don’t know if my OEM Banner is Group 6,7 or 8.
I think H6 = Group 48 & H8 = Group 49. IDK what group # is the same as H7.

I now have read all 310 posts! I had read this thread about 1 year ago.

Seems like many people swap their OEM smaller batteries (H6 size?) for the H8/group size 49 larger size and it does fit in the tray. Some question as to needing to add a nut and bolt for the last hole?

3rd link is Antigravity who sells Lithium lightweight batteries.
Thanks for the links.
I think when it is time to replace, I will either get Interstate MTX-49-H8
Or Bosch 49-850BAGM.

I actually have had that exact Bosch battery from Pep Boys in another car for 2+ years & using a Solar BA9 capacitance tester. It tested SOH = 94% and I only drive it 1x/week. It is 20 years old so doesn't have all the electronics my new Porsche has.

Antigravity

H6 = Group 48

H7 Group 94R

H8 = Group 49

They ALL fit in your Car.. .you just move the mounting bracket larger or smaller to accomodate. In most Cases you will have the H7 and H8 in the 911 series and the GT3 and GT2 will have the H6 sizes. Differences are that the larger battery have more Amp Hour Capacity.

Yes we do lightweight Lithium in those sizes also... and they have WIRELESS built-in Jump Starting so you will never be stranded by a dead battery, never be locked out of your frunk and you get a much longer life span... and they wiegh about 35 pound less.

You Tube