Rechargeable batteries and temperature

[Lightning Fish]

Hello:

I use a UK C8 light. It is not the rechargeable version with the higher watt light. I have switched from alkaline batteries to rechargeable NiMH batteries.

On my first dive with the NiMH batteries, after 20 minutes the light went out. Water temp was 50 F (10 C). During the safety stop, where the temperature is a little warmer, the light came back on. I am guessing that the loss of light was due to poor battery performance at low temperature.

Any suggestions on how to compensate for low water temperature? Or is this the problem? One idea I had, but haven't tried yet, was insulating the light with a neoprene sleeve.

Cheers,
Bill.

 

[diver_paula]

hmmmm... temp doesn't seem to affect my UKC4 or Light cannon, both with rechargeable NiMHs, like that.

 

[Lightning Fish]

hmmmm... temp doesn't seem to affect my UKC4 or Light cannon, both with rechargeable NiMHs, like that.

Yes, I would have expected them to work. Datasheets from Energizer's website show an operating temperature range of -20C to +50C at a discharge rate of 0.25 A. The discharge rate for my application is 1.35 A with a temperature of 10C. So I e-mailed Energizer to find out what the operating temperature range is for my application, if it is different.

Cheers,
Bill.

 

[diver_paula]

Hello again Bill.

There have been several threads regarding the UK lights and batteries. Duracell works better with UK lights than Energizers do. They tops of the Duracell batteries make better contact with the UK mechanisms.

One thread that explains.... http://www.scubaboard.com/t27228.html

Perhaps the answer is as simple as that?
Paula

 

[Lightning Fish]

Hello again Bill.

There have been several threads regarding the UK lights and batteries. Duracell works better with UK lights than Energizers do. They tops of the Duracell batteries make better contact with the UK mechanisms.

One thread that explains.... http://www.scubaboard.com/t27228.html

Perhaps the answer is as simple as that?
Paula

The batteries are supposed to be a standard size but, they are not. Imagine the chaos if everything was done to the same "standard" that the battery manufacturers follow.

I put a piece of carboard in the bottom of the light to make up for the smaller Energizer batteries. It works. (The C8 is also spring loaded but that didn't help). When the light quit the brightness faded away. If it was the size of the battery, and the cardboard wasn't reliable, then I think the light would have blinked off, and not faded away.

Cheers,
Bill.