Have you bought the Ctek yet? If not buy an optimate 4 from Amazon. It has a short lead that you can connect to the battery using an eye connector on each terminal, so it is connected all the time. On the other end is a connector that plugs into the lead from the Optimate charger, so all you have to do is unplug it from the short lead when you want to go for a drive. There is a little rubber cover to go over the end of the plug when not in use.
You have to remember to unplug it though!!!! I have forgotten a few times and dragged it out of the garage still connected. But it has just unplugged itself without doing any damage.
My 7 year old JCW
still has the original battery, it is a summer car and has been on an Optimate all its life.
The Optimate 4 does all sorts of battery checks, like stopping charging for 30 mins to make sure the battery is holding its charge ok.
It's about £50.00 But a lot cheaper than replacing the battery.