No, Corsart, I have a Genius charger - a model G1100, and as it says on the box, it's "a wicked smart charger!" I can leave it connected for days without any worry of overcharging. The thing is, I would start out with a fully charged battery, take a quick trip to the store, and the next day find that the car has gone into the "save battery" mode again, which made me think that the battery had lost its charge overnight. Now I'm starting to wonder if the "save battery" mode is triggered not by the condition of the battery, but by the ambient temperature. It's starting to get a little warmer where I live and yesterday, at about +5C (41F), the welcoming lights greeted me as I walked up to the car, indicating that all was OK. I wonder if, when the temperature drops below a certain mark, maybe zero C (32F), the car goes into the "save battery" mode regardless of how much charge the battery has. I dunno. I'm going to take Marc's advice and buy a battery tester. Yet another tool that I'll use maybe once a year, but I live by the mantra "There is no such thing as too many tools!"Not all trickle chargers are the same, you need one with the right amps. There's a correlation between amps and time to full recharge, and if you have a trickle with less than 5 amp output chances are you're not getting enough juice in it, the Corsair has an 800 CCA battery to power up and run all that electrical stuff. You need at least 5 amps, and 10 would be fine especially if you drive infrequently and it gets very cold between drives.
I sound like an advert here, but this is the minimum you want: https://www.amazon.com/NOCO-GENIUS5-Fully-Automatic-Temperature-Compensation/dp/B07W8KJH44/ref=sr_1_5?crid=17K4W0GXY1T5M&dchild=1&keywords=trickle+charger&qid=1614810817&sprefix=trickle,aps,189&sr=8-5