Keeping our 12V battery properly charged?

Any small trickle charger/maintainer will have a power cord thin enough to allow closing the hood or the trunk hatch. Quite often, I've left a trickle charger/maintainer connected to the 12v battery in the trunk and just closed the hatch and locked the car if I don't plan to use the car for a while.

12v battery life can be greatly extended by disabling the SKS system using the "key" button located below the steering wheel. You'll have to use the lock/unlock buttons on the FOB while its disabled, and will have to insert the FOB into the dash slot to start the car. You can go back to normal SKS use at any time by putting the button back to its normal position.

 

You can use the jump point under the hood, or crack one of the windows enough to feed an extension cord through, then lock the vehicle.

If parking in direct sun, with no expected weather, why not crack all 4 of the windows a few inches and save your HV battery from heat soak.

Curious how many times the catalytic has been stolen.

 

in your situation, i would simply put a maintainer under the hood when parked, drop the cord through the engine bay onto the ground, and plug in an extension cord.
removal when you're going to use the car would take a minute.

this is what i do with my rarely used pickup and it's oem 17 year old 12v.

 

As long as you're not in California this is a mild inexpensive inconvenience you can even mark the car some kind of way or paint the thing down there so it looks like it's been fooled with and people will move on generally that sort of thing does work. But it sounds like you're 12 volt maybe on the way out

 

Just curious. Which solar charger did you try?
This one by Battery Tender works for many people and uses the OBD2 port for easy connection. No need to mess with battery connections.
There is an extension wire also to reach all the way back to rear window if that’s desired.