Backup Light Batteries

[Griffo]

I hope this hasn't been done to death before, I did search but couldn't find anything.

On the GUE equipment page, it recommends using non rechargeable batteries in the backup lights. I'm wondering whether people really follow this advice however.

On the one side, I'm sure that yes, standard batteries would have a more consistent run-time. Assuming they are fresh.

On the other hand, does this mean that you throw out your batteries every time you use your backup torch? I mean, if you average 3 hours burn time, and you use it for an hour, do you then discard the 2/3 full batteries?
I would have thought that modern rechargeables that you can top up after every dive would be better? (and that's not to mention the conservation angle of all those discarded alkalines)

 

[rongoodman]

If I actually had to use a back-up light rather than just test it, I would replace the batteries before the next dive, no question. It's not like it's a common thing to have happen.

 

[Seraphimx]

I don't dive in Caves, but basic open water & finished fundies last summer.
I don't change my batteries every time, except when the backup light becomes mandatory.
Night dives. I dont cave dive, but same applies. I don't do Deco, but same applies.

A light is always good to have to signal, but if you're in an "all usable" no-deco situation. If something happens you can just thumb the dive.

 

[JamesK]

If I actually had to use a back-up light rather than just test it, I would replace the batteries before the next dive, no question. It's not like it's a common thing to have happen.

Same. However, I don't throw away the batteries. I use them for other items around the house.

 

[Dsix36]

Rechargeable batteries tend to self discharge much faster than standard alkaline batteries do. Thus is makes rechargeable batteries a bit more unreliable unless the charge is fresh prior to each and every dive. Even then the batteries are discharging while you are diving and will not be fully charged when/if you need them.

Backup lights get brand new batteries put in them every year or every time they are used (not including a quick test to verify operation).

Alkaline batteries are more reliable and if you are in need of a backup light, more than likely, you will really appreciate having one that will actually turn on and work.

 

[rlynch]

General rule of thumb is replace every 6 months or before a big dive/cave etc. i just recycle them into the household stash of batteries and install a fresh set. so far mine have only been handed off to others or turned on to verify they work before everydive. I've never needed to use them myself (knock on wood)

I also dive a Canister light as my main light.

 

[LiteHedded]

i replace them every six months or so. or after any extended use

 

[kathydee]

In caves we test the back up light battery voltage before dives. Once it falls below a certain voltage they are recycled for other purposes.

On most OW recreational dives I just check to make sure b/u lights are functional and replace batteries as needed.

If you dive with a primary light can and are not doing class drills, you rarely deploy your backup light.

 

[PfcAJ]

I test for operation pre-dive and replace every ~6 months or after extended use. They've got to be non-rechargeable. I'm pretty good about not using them for purposes other than a backup (like digging around the truck at night looking for gear), and if I do, I use the LED one. The halogen bulbs have a finite life, too.

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

 

[Scott L]

Oh, great. Now I have to buy a voltage meter?