I need to leave my 992.1 with lithium battery in the garage for about eight weeks this coming summer, so I’ll need to use a battery maintainer. I’ve already received some very helpful advice from this forum, but there’s one additional concern I’d like to clarify.
I live in an area where we typically experience one or two power outages each summer, usually lasting anywhere from a few minutes to a few hours, particularly after thunderstorms.
My questions are:
1. If I use the 12V cigarette lighter socket for battery maintenance (which has been recommended by mechanics at two different local dealers), are there any battery maintainer brands that will automatically restart charging after a power outage? I’ve heard that the Porsche OEM maintainer may not automatically reset. I’m not sure whether a NOCO charger connected with a cigarette lighter socket adapter would work in this scenario.
2. If I instead install pigtails directly to the battery, which battery maintainers are able to automatically reset and resume charging after a power outage?
Any insight or recommendations would be greatly appreciated.

Do a direct connection to the battery and you can have the quick connection come out by your windshield wiper hidden by the lip of the frunk.

get a ctek charger (get the correct one if you have a AGM or LiPo or get the antigravity charger. Both will save the mode and continue charging after a power outage.

the Porsche charger and others do not restore mode and you have to reset as you indicated so go with one of the ones I mentioned above.

I have a "Battery Tender" detects both agm or lithium ...pigtails are so easy to use..I pull plug right out the frunk to an AC source.

The cigarette lighter outlet is a horrible option.

99% of owners can't tell you the sequence to keep it "alive" past 30 mins.

Just direct wire to battery.

A few things...
As another said I would NOT go in via the Cig Lighter outlet.... regardless of the Mechanics recommending it... they are not understanding that in many Porsches this Cig Lighter Charging method can "time-out" and as documented on Rennlist it is hit and mis.... and with your Porsche Factory Lithium Battery you DO NOT want to mess around this because it is also reported and documented on Rennlist that many have trouble if they get over-discharged because they are not waking up from their protection mode because of a relay malfunction. So get a brand Charger you like for Lithium Batteries and connect the pigtail to the Batteries positive and a ground point like a screw of a panel near the battery or the Negative Jumping lug with a hose clamp and then you have a solid absolutely reliable connection without the risk of the time-out issue.... my point is just don't take the risk via the Cig lighter.

Now as far as Chargers.... Antigravity Batteries offer something which has features that are a bit more modern and fuctional than the typical CTEK brand Charger.... meaning the CTEK does not have a Lithium Battery BMS wake-up features, yet our Antigravity Super Charger does. The CTEK does not have a digital screen which informs you of the actual voltage and current going into the battery and the CTEK only has the dummy lights to explain where it as at where, but our Antigravity Super Charger does. The CTEK can only charge Lithium , whereas our Antigravity Batteries Super Charger charges both Lead/Acid and Lithium Batteries. Also our Antigravity Super Chargers will begin charging on the last profile that was used in the event of a Power Outage as you asked about, which I believe CTEK will also do. Both are fine Chargers, just depends on what you prefer. NOCO is also fine.... but in comparison of the Chargers, the AG Super-Charger does have more functions and abilities than the others at the same price range. Finally I would suggest you go with 10 Amp version of chargers with Modern Cars, the extra amp will charger batteries much faster and allow for BMS resetting much easier.

https://antigravitybatteries.com/products/super-chargers/sc-10/

https://www.youtube.com/watch?v=oTTlHKNi4KM