LEAST corrosive battery chemistry???

[Sub_Umbra]

The subject only refers to rechargeable chemistries for
AA, AAA, C and D cells.

Okay. All cells will leak under the right (or wrong) circumstances.

Will they all do the same amount of damage to a given light if they
happen to leak?

Will one chemistry do less damage if a cell leaks?

Will one chemistry do the same amount of damage faster or slower
than another type if there is a leaker?

Another way to put it: What is the safest rechargeable chemistry to
use in your favorite light(s)?

Any input will be appreciated.

 

[IsaacHayes]

Well, we can take SLA off of the list that's for sure. I'm not sure if there is SLA in the form of aa/c/d etc though. I'm not sure what the pH of the checmicals in NiCAD/NiMH are, but NiMH has less toxic heavy metals but of course that still doesn't answer your question. I'm thinking that they are neutral perhaps???? Not sure... Interesteing...

 

[Nubo]

AGM batteries are lead-acid but quite leak-resistant. The electrolyte is totally absorbed in thin sheets of material. No corrosive gases are generated. I recall reading of demonstration where someone fired a bullet through one and it just kept on working with no spilled electrolyte.

The original spec for the Miata was an AGM battery, which was remarkably small and well-suited to its placement in the enclosed space of the trunk. That battery lasted me 7 years. There are also smaller ones made for other uses, such as alarm systems, etc. I used 6-volt versions in bicycle lights. Both the car battery and my smaller ones were made by Panasonic. The 6v, 4.5 AH version was within the realm of flashlight size; there are smaller ones also.

http://panasonic.com/industrial/battery/oem/chem/seal/index.html


Their drawback is weight. Even though they are lighter than conventional SLAs due to reduced volume of electrolyte, they're still fairly heavy compared to other rechargeables.

 

[Zelandeth]

I tend to think in terms of everyday battery types that NiCd are proably about the least corrosive - NiMH I have no experience with though. Never had any trouble with damage done by the few leaky NiCd's I've encountered though.

 

[IsaacHayes]

I saw a leaky NiCAD today in a motorola walkie talkie. It had blue/white crystals corroded looking all over one contact.

So It's got something caustic in it.

 

[Sub_Umbra]

[ QUOTE ]
IsaacHayes said:
I saw a leaky NiCAD today in a motorola walkie talkie. It had blue/white crystals corroded looking all over one contact.

So It's got something caustic in it.

[/ QUOTE ]

I've read on other threads that NiCad 'juice' is very corrosive stuff, but blessedly, I have no experience with leaky NiCads.

Has anyone out there had a NiMH leak in a light?

How corrosive was the mess?

 

[mrme]

Is someone up for an experiment?
All you would need are some expendible batteries, some metal pieces (preferably spring steel, copper and plated copper), a hack saw and a digital camera.

I wish someone had asked this a few months ago before I started grad school and I had the time to do this kind of stuff.