Hey,
I have a little query.
I have a small understairs cupboard that I would like to light up when the door opens. My problem is there is zero electricity or outlets in that space.
Is there a battery pack powered device I can use, or would of just be simpler to get those non smart motion activations lights?
Probably easier to go the non-smart route for that one. I don't know of any lights that are controllable that are battery powered. The problem with battery powered actuators is that they can't go to sleep because they have to wait for a command to be received to turn on. Sensors can sleep between events because they can wake themselves up when they sense something.
I don't like saying go low tech, but I'd have to agree with Ryan.
I have so many battery devices, and just today one had semi-died. It wasn't reporting door open, but was still reporting temp/etc. Had no clue, and took a while to figure out what was wrong as it was showing recent activity. Then I looked again, and it said battery "30%", which often means "battery 0%". Got a drawer full of batteries now, semi-expensive and all difference sizes. You'd likely have 2 batteries... the contact sensor and the light. So, I'd have to agree to avoid that.
Some device that uses standard batteries, and only turns on when the contact is open (cupboard door), via old fashioned wire is probably best 
So, I wanted to see if something like that was available. Sortof. Assuming your cupboard is what I'm picturing in my head, I'd look into something like this (not necessarily this one, and obviously I've never tried one nor endorsing them!).
I use something similar in most of my closets. They were not wired and I didn't want to pull wire to all of them. These lights are triggered by motion and also have a light sensor so they don't go on if there is light (it has to be pretty bright to prevent them from coming on). About seven inches long. They use four AAA batteries. Battery life is close to a year. They are mounted to a magnetic strip that has adhesive on it - this makes it a little easier to change the batteries. I got a package of four or five several years ago.
Thanks @Ryan780 @AndyM @Eric.C.Miller I thought that would be the case. I did think snout running cable to the space (or at lease getting and electrician to) bit it’s not worth the effort
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