Back up lights...

[OneBrightGator]

Let the fun begin!

Alright, so there has been a lot of talk recently about backup lights that got me thinking. From what I know, the use of disposable batteries in backup lights comes from reliability. Alkalines hold a charge over a period of time better then the rechargeables of yester-year, a rechargeable primary was an assumed risk as the cost of disposable primary batteries would be too great, and if your primary #### the brick, you had awesome, alkaline-using backups.

Fast forward. Today we have, IMO, very dependable rechargeable batteries. So... I am pondering the idea of using rechargeables in my backup lights also. If I make that decision, I am trying to decide if I want to carry them like we do currently, or run them on for the dive. Quite a few backup lights failures I have heard of happen when trying to turn them on, leakage through an o-ring, unscrewing, etc. Doing this would eliminate that risk. Also, this would force you to recharge all your batteries after a dive. There is the concern that they would shine backward at your buddy. At this point, I am leaning towards a bad charge being less of a risk then a 9-10-11 month old alkaline crapping out on me.

Please discuss. Thanks.

[aainslie]

Hmmm... just thinking about this, I'll start by saying that my strategy is to have a backup on my head permanently on during the dive. As you say this helps verify that it's working.

I also take 3 added backups - two on my harness, one in a pocket. I test each one before each dive. I'm a bit paranoid since I dive solo a lot.

With this strategy, I think rechargables on ALL BUT ONE might be OK. My suggestion. Alkaline batteries are bulletproof and last forever ( I have some working just great that have been in one light for about 8 months now!) so I think having one light with these (and replacing them more often than I do!!) would be good.

On a similar vein, I feel that LED's are a much better bet than incandescents for backpus because of their very low current drain.

[billyf]

I use Ni-MH Rechargeable in all of my lights.
Been using them for over a year and never had a problem, I just made a one hour exit on one of my backup lights.

[Wizard]

And the source of the batteries and charger is?

[OneBrightGator]

Any reputable company, a major manufacturer such as Duracell or Energizer or distributor such as batteryspace.com or batteriesplus.com.

Is there something you are eluding to?

[Cave Ranger]

I carry 1 Sartek primary 10 watt HID with a 4 hour burn time. I carry 1 halogen Salvo backup and 3 LED backups of various sizes using alkaline batteries.
If all of those fail during the same dive along with the 3 or 4 my buddies carry?........Well I guess it's just fate.
I tried the rechargable Nimh batteries for my underwater camera once and became disillusioned with how quickly they drained and how they died with no warning. For now I'll stick with Alkaline batteries. Besides, 3 backup LED's with fresh batteries and a 8-10 hour burn time each should qualify as overkill. 5 lights will likely last longer than your gas supply.
I dunno man...you can only do so much

[tomhauburn]

One option worth trying and testing is the new class of rechargeables that hold their charge over time. They have figured out how to make them not discharge over time. As with most things in life there is a negative. The ones I saw were AA and had 2000 Mah vs the newer regular ones being 2400-2600 Mah. I have not done the testing but maybe someone has and can give us their results.

Tom

[FW]

One big advantage of Ni-MH is, you can charge them before each dive, and not run the risk of the "memory" that Ni-Cds had.

FWIW, I recently "borrowed" one of the new super bright LED backup lights. It was as bright as a 10w HID. I could signal guys with 21w HIDs. You could scooter with it, if necessary.

[OneBrightGator]

Yeah, I'm not too worried about them holding a charge for long periods of time, I have learned to pop my cannister packs on their chargers a day or two ahead of time, so doing the same with backup light batts won't be a problem.

I think initially if/when I do switch over to rechargeables I'll do a few burntests to check them and still carry a set of aklalines in my SAD kit.

Come on... no one balks at this idea? Even the keeping them on all the time one? (btw, my new backups are LEDs)

[FW]

(btw, my new backups are LEDs)

I have been using LED backups for 3 years, but these new ones are BRIGHT!