Since my car is currently parked outside in a Northern European winter climate, and only being used for short distances, the battery is sometimes just barely able to start the car, sometimes it can’t cope at all.
So my idea was to hard-wire my (existing) battery charger and run the mains cable to the outside, so I can quickly hook it up to mains power to top up the battery. (I’ve seen a power plug on the front of some vehicles operating in colder climates, such as Sweden or Canada—not sure if that was for a battery charger or something else.)
The charger I have has a 7.5A fuse—I am aware that this is just enough for charging the battery, not to run any major consumers and certainly not to start the car, so I would obviously disconnect it prior to starting the car.
Can I use a battery charger in this manner? Or will that cause issues if the charger is connected to the battery all the time, even when the mains side is not plugged in?