Battery holder

I have one of those inexpensive black plastic 6xAA battery holders. I recently discovered that if I press on it in a certain way the power cuts out, which is kind of a problem for my project. It's worse if the holder has NiMh batteries in it, since they are larger in diameter, but it happens with very type of AA battery I've tried.

I was wondering what alternatives I might try.

  • A better holder than this cheap plastic one?
  • Building a box to house the holder?
  • Making my own battery holder?
  • Soldering batteries together??
  • A better holder than this cheap plastic one?

Best option.

  • Soldering batteries together??

Don't even think about this unless you have a big heat source and you like explosions.

That's what I was afraid of. The explosions part, I mean. What happens when you overheat a lithium AA cell?

Can you recommend a particular holder? All the ones I see in searches have that same cheap slightly flexible quality to them. Weight is also an important consideration for this project but reliability is ultimately more important.

I would recommend that you mounted the cheap battery holder on a piece of aluminum plate or acrylic plate to stop it flexing.

I don't mind the tiny cost of using acrylic. But (like ceramic) it's a heavy material. Ounces matter in this project.

If it were just a matter of mounting it to one piece of rigid material that would be one thing. But the access panel to the batteries is also particularly flexible. It's kind of a piece of junk.

Wrap tape around it? Bend the springs a little so they line up better with the batteries?

Of course the real solution is "Don't press on it that way!"

It will be in an environment where it might be pressed upon lightly on occasion. Tape, being flexible itself, won't do much if anything to prevent the problem.

The springs all appear to make contact, as do the positive terminals. I'm not really sure what the exact failure is since I can't see inside of it and it doesn't fail when the access panel is removed.

I think the real solution is a rigid container for the batteries. I may just have to put it inside some other box until I can find or build a better holder.

jboyton:
Can you recommend a particular holder?

I have had good luck with two and three cell cages from...

Their six cell cages are listed here...

This holder looks like it would probably be better, although it needs a cover. This is the one that I currently have.

I went at it with a soldering iron and a metal file and now it seems stable. But I don't trust it.

Have you contacted MPD?

Contacted them? No, but I plan to order a different type of holder and see how it goes. It's also possible that the one I have is just a lemon.

Meanwhile it forced me to make my code a bit more robust in terms of recovery from power failure.

jboyton:
Contacted them?

I would (and typically do). The entire cost to you is one email; about five minutes of your time. The benefits to you are: They send a replacement. You can use their response to gauge what sort of vendor they are and whether or not you want to continue doing business with them.

Why not give it an extra advantage. Solder 6 rechargeable nicads in series and make it rechargeable. Don't even use a battery holder. I have experienced the same thing with a metal detector's batterys and I hate those cheap holders. If you want to use them use the 2 battery holders 3 of them. There is not as much stress on the holder with the 2 battery types.

Stating the obvious:

Ni-MH cells are sold with solder tags for real-world applications. You can even get 18650 cells with tabs.

That said, some zip ties in the appropriate places on the present battery holder would ensure contact without too much extra bulk.

The application involves cool temperatures (~0°C) which favors using lithium. Weight is also important and NiMh cells have an energy density less than half that of lithium AA. There's probably a better battery solution for my project but the issue here is just one of making good contact with the batteries I have.