miniature battieries

[kingmalik]

I know the two main battery chemistries for miniature button and coin cell batteries are Li/MnO2 and Zn/AgO. What I'm wondering is whether or not Li/MnO2 coin cells can be made even smaller. They're much cheaper to produce and have a higher voltage than the Zn/AgO batteries. Can anyone tell me the reason why they can't be made as small as the AgO button batteries?

 

[MikeHalloran]

How many millions of them are you prepared to buy?


Mike Halloran
Pembroke Pines, FL, USA

 

[kingmalik]

I'm sorry, I don't quite understand you. Is that your answer or a proposal?

 

[MikeHalloran]

That's the answer: If you are willing to buy enough product to amortize the tooling or just to pay for the tooling outright, you can get pretty much any product in any size you want.



Mike Halloran
Pembroke Pines, FL, USA

 

[kingmalik]

Thanks for your input, I really appreciate it. I still wonder though why it isn't being done. I'm sure they have the necessary tools already if they make silver oxide batteries. I know you could probably make a product as big or as small as you want by just scaling it up or down, but maybe a smaller coin lithium battery has a capacity so small that it's not lucrative to produce? That's more of what I'm wondering I guess.

 

[IRstuff]

Didn't you already answer your question? Lithium cell voltage is 3V. That means that you burn twice as much power as a silver cell for the same circuitry. Most silver cell applications only require 1.5V to run. Anything else would simply be wasting energy density.

TTFN

FAQ731-376

 

[kingmalik]

How much power that is burned by lithium cells wasn't my question exactly. You know how the diameter of lithium cells are typically 10mm or larger? My question is, if they were made smaller, say 5mm in diameter like the smallest silver cells, would they hold enough power to be useful for low drain electronics?

 

[IRstuff]

I answered that question, didn't I? Double voltage means double the power draw. If the lithium batteries aren't at least 2x more eneryg dense, you have lower battery life.

TTFN

FAQ731-376

 

[itsmoked]

IR there are applications that need two 1.5 cells in series.

I want a better answer than "It's too much voltage".

Keith Cress
kcress -

http://www.flaminsystems.com