I know sweet FA about what I’m asking but ..
I’ve acquired one of these …

..could I convert it into a charger for an ipod/phone etc.

Probably, depends on the specs. Looks like it outputs 12v so you could connect aniPhone car charger to it.

Yes. You can buy the ‘socket’ end of a car cigarette lighter and put in place of the ‘plug’ one (or you can find them with the solar bullet plugs attached sometimes). Then buy a cigarette lighter usb charger and use it to charge anything that charges from a USB. Make sure you get one that works with Apple products as not all do.
It won’t be great, but it should trickle charge.