Rechargeable batteries?

[jiveturkey]

Is that video available online anywhere? I've seen a previous one with some fantastic cave diving footage at the end. Dream Theater provided the score I believe.

 

[RTodd]

I recently watched the DIR 3 DVD with George explaining some of the simple stuff about backplates and rigs. When he was talking about small backup lights - the kind that use C-cells etc - he said not to use rechargeable ones for such lights. As there was no further explanation given as to why I was wondering what the reason was.

Alkaline - test voltage of the battery before the dive and based on this there is a very predictable discharge (i.e. known burnttime). Rechargeables can show a full charge and then crap out a few minutes later. Primary lights and scooters use rechargeable batteries and are the most problomatic/ weakest link of any gear we carry with us.

 

[mer]

Alkaline - test voltage of the battery before the dive and based on this there is a very predictable discharge (i.e. known burnttime). Rechargeables can show a full charge and then crap out a few minutes later. Primary lights and scooters use rechargeable batteries and are the most problomatic/ weakest link of any gear we carry with us.

Which is why we all carry a 13.99 Radio Shack Special voltmeter, eh? This way you can tell how long your backups were on before your buddy noticed and know if you need to replace or not.

 

[HarryH97]

Yes....that was my first thought actually, that it might be that sort of reason. Still, rather than guessing I thought I'd ask. I'll be using my UK SL6 as primary backup from now - so I'll keep the Duracells in that.
What Jonnythan said about NiCaD and NiMH is also true. I'm considering going with rechargeable 4000 mAh "C" cells for the light cannon. They seem to be the most powerful that I can find looking around. I'll have to check what's available in Japan.

There's a 5000 mAH NiMH C cell battery from www.batteryspace.com made by powerizer - under $30 for a set of 8. OK, yes, I'm guilt of using them. I'd swap them out in overhead for alkaline, but mostly ocean, lakes out here. If one of the cells cut out, I'm banking on the other two to still give me juice until I get 2nd backup scout operational. Call me the 'S' word if you want. I can handle it!

Sincerely,
H2

 

[RTodd]

There's a 5000 mAH NiMH C cell battery from www.batteryspace.com made by powerizer - under $30 for a set of 8. OK, yes, I'm guilt of using them. I'd swap them out in overhead for alkaline, but mostly ocean, lakes out here. If one of the cells cut out, I'm banking on the other two to still give me juice until I get 2nd backup scout operational. Call me the 'S' word if you want. I can handle it!

Sincerely,
H2

It depends on the use. If you are sticking NiMH in a scout that you carry around to look into holes on an open water dive and it is effectively your "primary" light that is no big deal. However, if you are putting it in your backup light which should only be used in emergencies where alkalines will last 6 months anyway then yes that is a stroke move.