I try to keep my cars on trickle chargers (Noco Genius 5 in my case) when not driven regularly, because regularly killing $300 AGM batteries gets expensive. Th

I try to keep my cars on trickle chargers (Noco Genius 5 in my case) when not driven regularly, because regularly killing $300 AGM batteries gets expensive. That said, I'd expect most cars should be able to manage, say, 2-3 months. It's when I exceed 4 months with some regularity that battery life starts getting sketchy. If you're driving the car every weekend, I'd expect that should be plenty. Note that fancier cars with more electronic features don't do well when only driven short distances. If you only drive 2-3 miles at a time, you might be discharging the battery faster than you're charging it.