I did a search for battery operated table lamps and found this:

SITE 1

SITE 2

As many are indoor/outdoor make sure the one you like is battery operated and not solar powered.

It is not expensive to have an outlet installed so I would check that out first. But with LEDs you have some nice looking battery powered wall sconce for sure.

https://laurelberninteriors.com/2017/02/08/solution-table-lamp-cords/

Someone asked a similar question recently, looking for a battery pack to power an existing floor lamp (I think...). I was able to find some appropriate equipment searching for "AC battery power supply."

https://thewirecutter.com/reviews/the-best-portable-ac-power-supply-so-far/

Reminds me of that one apartment I had where one bedroom had power in two places: one ganged with a light switch 3' off the floor and between the room entrance and closet door (pretty much useless) and the other was behind the cast iron radiator.

I second looking into whether an outlet can be added easily, as it will benefit you in the long term and any potential buyers that are savvy enough to look for such things. We recently had one added to our master bedroom to power one of the nightstands. All that was required was a hole in the ceiling, a hole high up on the wall and the cutout for the outlet itself. If you have an unfinished basement or crawlspace below it could be even simpler. Cost was around $200.

Call your electrician and have an outlet added. It's not a big deal and worth the expense , which is little.

We offer a selection of rechargeable designer lamps at Modern Lantern.