JET992

I too hook directly to battery terminal (before collection of the car I Amazon'd my Porsche dealer a ctek "connect" cable and asked them to attach it for ease of use). I have taken this approach with my previous two 991's (I attached those ones myself) and seems to work well.

neil.schneider

I just put mine on the trickle charger about an hour ago. It’s been a week sitting in my garage due to the bad weather. It looks like next week is going to be kind of crappy too.

RD16RR

In the northeast it's definitely safer to keep it fully charged.....

$49.00 for a Battery Tender at Costco -- alligator clips or pigtail - simple

DemonBarber

I use the Porsche battery tender purchased from Sun Coast online, and I wired it directly to the battery and frame with a quick disconnect. Works really well, but I will say that every once in a while it turns itself off. Not sure why, but maybe our power interrupts every now and then for a fraction of a second, or maybe it's just a product design problem. Knowing what I know now, I probably would buy the ctek lithium charger like I use on my M5.