Backup Light Batteries

[PfcAJ]

Trey said something rather colorful about folks without a multimeter

In all honesty, if you test the lights to make sure they work and replace the batteries at interval and/or after extended use, you don't need to test the voltage all the time. That probably does more for potentially causing failures than preventing them, anyway.

 

[LiteHedded]

Trey said something rather colorful about folks without a multimeter

In all honesty, if you test the lights to make sure they work and replace the batteries at interval and/or after extended use, you don't need to test the voltage all the time. That probably does more for potentially causing failures than preventing them, anyway.

are you going to share it with everyone?

 

[PfcAJ]

Lol nope!

 

[mathauck0814]

I think it's OK to use rechargeable batteries provided:

a) You replace them when they start to build a "memory" and their charge starts to decline.
b) You're diving LED lights that won't be impacted by the different voltage (my understanding is that rechargeable batteries are ~10-15% lower voltage than regular batteries which can impact the output of an incandescent bulb - I could be mistaken)
c) You're still charging the batteries (or at least verifying that they're holding their charge) between every dive, even when they haven't been deployed.

One of the other things that sort of stuck out in my mind when I took my first cave course was that if I changed all my batteries at the same time the odds of all my lights being dead simultaneously were higher. I'm not sure if there's a best practice here about a rotation (other than new batteries on every dive) and it's not something I've ever put into practice, but something I definitely noodled on for a bit.

 

[kathydee]

Once it falls below a certain voltage they are recycled for other purposes.

Kathy, what is the 'certain voltage' that you replace your batteries at?

When the voltage drops below what's printed on the batteries. For C batteries, it's 1.5v

Trey said something rather colorful about folks without a multimeter

Come on, share it

In all honesty, if you test the lights to make sure they work and replace the batteries at interval and/or after extended use, you don't need to test the voltage all the time. That probably does more for potentially causing failures than preventing them, anyway.

Just doing what I was taught.

 

[PfcAJ]

You'd be surprised how many folks have NO IDEA what the voltage of those batteries are or what the stack voltage should be.

I know what you were taught, but I still think its not worth the risk of compromising a good seal (which will render the light pretty useless). Think about it and get back to me in 6months.

As far as the George thing goes, the interested reader can find it

 

[kathydee]

You'd be surprised how many folks have NO IDEA what the voltage of those batteries are or what the stack voltage should be.

So for those folks who have no idea - "stack voltage" is just where you test the batteries together (I leave the batteries stacked up in the light). In a 3 C-Cell battery light, simply multiply 1.5v x the number of batteries. The voltage of 3 C batteries should be equal to at least 4.5 volts. If the number is lower, then one battery probably needs to be swapped out.

 

[CrispyCritter]

Do the "low self discharge" batteries (e.g. Sanyo Eneloop or Powerex Imedion) close the performance/reliability gap between NiMH and alkaline?

 

[PfcAJ]

nope.