Cave Diving Backup Lights / Rechargeable Batteries

[tursiops]

Good question...preferably no thru hull fitting. Either magnetic or twist on/off.

Of course there is the DGX 600 TWIST Handheld Light, also available with a button. Beware of buttons on lights in pockets.
But I'd be tempted to look at the new XTAR D20. The other XTAR models perform well and are robust.

 

[JonG1]

I find that the twist on/off will switch on though under pressure unless you back off the contact, but then you risk a potential flood, if you've gone too far.

Just have to check them on way in especially if in a pocket.

 

[greeniguana]

Of course there is the DGX 600 TWIST Handheld Light, also available with a button. Beware of buttons on lights in pockets.
But I'd be tempted to look at the new XTAR D20. The other XTAR models perform well and are robust.

I've been using a DF30 for over a year, I think the brand I have is Volador. 2 18650s and a magnetic twist switch.

My 3rd light is a late 1980s model 4 AA Tekna twist on upgraded with an LED bulb. That thing is bullet proof.

 

[rjack321]

I love the CR123 light monkey 2W for my pocket. I actually put one of those on the side of my primary goodman too. (in the little LM loop holder).

I have a couple of 18650 powered lights with push buttons that are ok, but I dont totally trust them to stay off until needed. Thankfully they are small and not too pricey so I can carry a couple plus a more conventional C power LED twist light or two. Many of my systems are sumps with dry bits to hike over/through. Having multiple lights for dry caving delays is super important so I carry 3 or 4 total even if that's far more burntime and redundancy than I need for the actual diving.

 

[stretchthepenn]

To date I only use Energizer or Duracell non-rechargeable batteries in my backups.

I talked to Richard Morton at Shearwater USA a few weeks ago about batteries for the Perdix. He advised me to avoid Duracell and use Energizer Lithium because he's seen scores of ruptured Duracells but only one bad Energizer. I suspect the same advice may well apply to lights.

 

[rjack321]

I talked to Richard Morton at Shearwater USA a few weeks ago about batteries for the Perdix. He advised me to avoid Duracell and use Energizer Lithium because he's seen scores of ruptured Duracells but only one bad Energizer. I suspect the same advice may well apply to lights.

Richard keeps repeating that over and over. Nobody else has seen or reported this behavior with any alkalines although I have some many year old energizer ones that leaked in an O2 analyzer. Consider me skeptical until this phenomenon is more widely reported by more than one person.

 

[halocline]

I had a set of AAA duracells leak into one of my piranha back up lights. When I told them that the batteries had leaked, destroying the battery carrier, they asked if they were duracells, and said they had complaints about duracells leaking. So I switched to energizers, we'll see if they fare better.

 

[Doc Harry]

For years, we have been using rechargeable batteries in our primary lights, but rechargeable batteries are not reliable enough to use anywhere else? This is, and has always been, bull excrement.

Rechargeable batteries are superior to throw-away batteries in many respects. Don't believe me? Okay, then answer these questions about the brand-new throw-away batteries in your light:

What is the voltage of each battery?
How many mAh does each battery have?
Are all of the batteries in your light matched in volts and mAh?

I have had PLENTY of brand-new throw-away batteries have ZERO volts and ZERO mAh right out of the package. In fact, a week ago I bought a 16-pack of AA Energizer batteries at Lowe's and every single one those batteries was dead.

On the other hand, with a smart charger I can answer all of the questions above with each and every rechargeable battery that I own. Not only that, I also have a record of the history of each and every battery, and so I know which rechargeable batteries are still going strong and which batteries are beginning to fail and need to relegated to children's toys. Furthermore, with a smart charger I can cycle and refresh the capacity of my rechargeable batteries.

Rechargeable batteries are far superior to throw-away batteries.

 

[Capt Jim Wyatt]

For years, we have been using rechargeable batteries in our primary lights, but rechargeable batteries are not reliable enough to use anywhere else? This is, and has always been, bull excrement.

When we begin a cave dive we turn on our primary light prior to entering the cave. We continue the dive until the light fails and then deploy a backup light. If we have three lights with rechargeables we are then relying on three lights batteries that not everyone is convinced are as reliable as non-rechargeables.

I am not convinced this is a good idea, however I am not convinced that I am correct either. But I know that I would rather err on the side of caution.

 

[loosenit2]

DGX600 Burn time 18650 vs cr123a

Thought I would post this in here as well. Recently got a wild hair and tested a dgx 600 using cr123a batteries. Worked great and got a 2:43 ru time, more than twice as long as with DGX 18650 battery. A little less output but still good.