Solar trickle charger

[crv_user]

Is it a good idea to have a Solar trickle charger connected to the battery all the time ? I have a 97 CRV with still the original battery. It shows no sign of any defect. I am working evening shift so I do a lot of short trips in the evening with the light on. Some one told me that I can use a solar trickle charger to keep my battery charged all the time during the day while the car is sitting n the drive way.
The solar charger is plugged into the 12V accessory outlet which need the key to be in accessory position. I don't want to leave the key in the car while it is sitting in the drive way all day long. But I think I can do some modification to have the 12V outlet connected to the battery all the tme. But I want to know if it is a good idea to have the trickle charger connected to the battery all the time before I make any modification. Any comment ?
If there is no concern on making the 12V accessary outlet life all the time, what will be the easiest modification ? Perhaps just bypass the key switch ?