Dive Light Battery Explosion

[Skuba Skot]

I don't know if this is the correct place for this post, but wanted to know if anyone ever had a similar experience.

I have several dive lights, all from a package. I knew some of the lights needed new batteries. On the way to the dive site, I asked my wife to open the lights and tell me how many batteries and what types I needed to purchase. She told me then reclosed the lights. We purchased new batteries.

At the dive site, I was opening a light to replace some AA's, and when I did there was a loud explosion. I dropped the light, as it hurt my hand, and scared me. It was the 3rd of July, so divers asked me why I was popping firecrackers.

I was curious if it is due to the gel in the batteries compressing at depth, or something else. Anyone have any ideas? Has this happened to anyone else?

 

[ibj40]

My experience, and I am sure there are others here who can provide a more technical explanation, is that when water (especially salt water) leaks into a battery compartment, it begins a chemical reaction that causes pressure to build up in the compartment, and what you heard was the instantaneous release of that pressure. If you look at the batteries, you may also find one or several for which the outer coating or casing has been damaged.

This is an important lesson in making sure that the o-rings are in good condition, that they are fully seated, and that you have lubricated them so that they achieve a good seal when the compartment is closed.

Hope you weren't injured.

 

[Marek K]

What kind of light?

There's another possibility. Sounds like you were using normal, non-rechargeable batteries?

An issue when using rechargeable batteries in dive lights is that they generate hydrogen gas when operating. Some manufacturers (like Ikelite) recommend not using rechargeables apparently for that reason.

The Ikelite PCa, otherwise a great little light, seems particularly susceptible to this with its latch closure. It's been known to "explode" under lessening pressure while ascending.

Many lights also have some kind of hydrogen-absorbing material in them, even when recommending normal batteries. So that tells me this may be something that happens with all batteries to some extent.

 

[Coralcop]

It is hydrogen gas generated from batteries. In my experience it has happened with NIMH as well as NICADS. I have had it happen to me and seen it happen to others, in everything from lights to sea scooters. I believe it is associated with the batteries being damp and then a spark source, such as the light being switched on, or the scooter motor being activated. While I have never seen anyone injured by this, there is the potential for injury. The sea scooter explosion was quite a sight. Some gadgets do have a small white absorber mounted inside, and I 've never known an explosion to occur in such.

 

[Damselfish]

I had this happen when opening a PT Shockwave after a trip many years ago. (regular batteries) When I started to unscrew the light the top shot across my dining room with a bang. There was a distinct smell which I figured as likely hydrogen. I've smelled it since when opening lights sometimes but only had the one "explosion." There hadn't been a flood or even any noticeable moisture in any of these cases so if it's moisture it doesn't take much. (Yet another reason to not leave batteries in lights for plane travel.)

 

[Shasta_man]

The smoke detector battery (9V) suddenly let out a crack and inspection found one of the batteries (1 for smoke, 1 foir light) had the bottom blown out. It had been in use more than a couple months and less than 6.

 

[gcbryan]

I've had the same thing occur as Damelfish describes except that my light had flooded. It seems that most of these happen with small (AA) plastic backup type lights. Just coincidence I'm sure. These are probably just the most likely type to leak.

I saw someone with a cannister light once jump off a boat for the dive and then climb back up the ladder a minute later with smoke (and heat) from some kind of a chemical reaction. She quickly got the hot (almost on fire) cannister body away from her body.

Some batteries seem to be sealed much better than other as I've had a rechargeable li-ion completely flood on a dive, the led light kept working, and after clean up and testing the battery was able to be reused.

It's best to keep salt water away from batteries however.

 

[bcaderunr]

I might add that any time you open up a flashlight that you suspect is contaminated by salt water - DO NOT LOOK AT THE FLASHLIGHT while you are opening it. When/if the nasty liquid contents come popping out under pressure the caustic spray isn't anything you want to get into your eyes or on your face. Learned that one the hard way (without any permanent consequences).

 

[Iruka]

One thing I've done, if the light is already flooded (usually you can see rusty-looking water in it) is to open the light under water.....in a big bucket or whatever....which I think would reduce the chances of acid spraying around or other possible shrapnel. Wouldn't want to do this if the light WASN'T flooded, of course.

 

[vladimir]

There was a distinct smell which I figured as likely hydrogen. I've smelled it since when opening lights sometimes but only had the one "explosion."

H2 gas is odorless. On ignition it forms water. Maybe some chlorine gas was liberated in the formation of NaOH and HCl? Just a guess, based on a dim recollection of Intro Chem. Or something else--hydrogen combines with just about anything.