Yes they transfer easily. But a second option is to use one of those lithium battery jump start packs which can also be use to charge phones and feed things like dash cams. I haven't tried mine for this purpose yet but it would be easier than routing the wire under the dash.
Given that the things are dirt cheap these days, it's probably easier to get one for each vehicle and leave it permanently plumbed in.
(Note to self - must get a Round Tuit)
