Fitting a 9 volt battery into a Polar Lights dome base?

[modelerdave]

This seems like a really dumb question, but I'm struggling with fitting a 9 volt battery into a Polar Lights dome base (1/1000 scale). I really don't want to plug this into a wall outlet if at all possible. Anyone have any pictures of how you may have done this? Thanks in advance.

 

[TazMan2000]

You can try three 3 volt coin batteries.

TazMan2000

 

[3Dsf]

A rechargeable LiPoly battery can fit into all sorts of spaces.

Li-Ion & LiPoly Batteries

If you want to take your project portable you'll need a battery pack! For beginners, we suggest alkaline batteries, such as the venerable AA or 9V cell, great for making into larger multi-battery packs, easy to find and carry plenty of charge. If you want to go rechargeable to save money and...

learn.adafruit.com

 

[modelerdave]

That's an idea! Thanks!

 

[Antsnest]

9v "PP3" sized batteries are generally a very poor power source. Generally the voltage is too high for most modern circuits built around a 3-5v requirement so you have to regulate that down which ultimately just wastes power. And they have very little capacity to start with. You are usually much better off with 3 or 4 AA cells - not that much bigger in size physically, but far greater in power capacity.

 

[star-art]

Those are good points. I was just doing some calculations for a light kit design and I saw double the capacity when using AA (but not AAA). I still prefer 9V though for a few reasons.

First, I've noticed current types are even lighter in weight than they used to be. Second, they can be a bit easier to install (all you need is a rectangular area and a pre-wired snap-on clip). For AA and AAA you often need some sort of specialized tray or battery box. This can take up more space.

My biggest reason though for choosing 9V is the fact I can trust them not to leak if they get left in a circuit for a long period of time. Often when I have a device powered by AA or AAA batteries and it doesn't get used for a while, the darned things leak. This makes a real mess that has to be cleaned up. If the damage is bad, I sometimes have to replace the metal contacts or even rebuild the battery compartment. That is not the sort of thing I'd want to deal with inside a model!

BTW, if you wire two white LEDs in series, 9V works great.