Ask Doctore Strobe: Rechargeable Batteries

New on “Ask Doctore Strobe”. Who is that strobe doctor you might ask? It’s my mate Gaetano D. Gargiulo, Italian-Australian underwater photographer, with a doctorate in electronics. Whenever I have an electronics question about my camera setup, I grill him. And, I thought his answers might be interesting for other underwater photographers as well! So, here we go:

Today’s Question: I use rechargeable AA batteries in my Inon z-240 strobes. How long do these rechargables usually last? I notice that the juice leaks out of them if I charge them, but not use them for a week or so. Should I store them in the fridge?

Doctore Strobe sez: The fridge is supposed to actually discharge them. I think that:

1) Maybe your batteries and your charger are not fully compatible, which brands are both?

2) Possibly the batteries are old or have been drained flat too many times. Strobes, particularly UW ones have this peculiarity, they try to squeeze you as much as possible. That is why I avoid to do 2 dives with 1 set!

Btw, Energizer and Duracell cells (rechargeable) are not working very well, in my experience. Panasonic/Sanyo, Toshiba, Aldi in this order are the ones to trust in INONs. INON circuits are pushed to the extreme and do not like >1.2V cells. To some extent this is an advantage as they can (ab)use batteries that are tired but it may turn into an expensive issue if you use powerful 1.6V rechargeable cells that instead are fantastic with Sea & Sea strobes. I think that part of the problem is around the battery compartment, INON strobes keep the gas inside and you risk a loud bang!

Question: So, no 1.6V, no 1.2V, 1.5V is ok?

Doctore Strobe sez: Yes 1.5V disposable, or 1.2 Panasonic/Sanyo or Toshiba rechargeable batteries. The Eneloop pro are just fantastic, and remember to change them every dive!

Question: So, get the right brand, and don’t drain them fully?

Doctore Strobe sez: Yes and after ~100 recharges you may consider buying spares…

I see that the Aldi batteries (as example [Aldi Australia, that is]) are very cheap ~5$ a set, they keep the firing with Eneloop pro until 70% of the dive and if I insist or abuse them (i.e. I keep the aiming light on) then when I charge them the weaker battery of the set may need > 12 hours to recover with the Sanyo charger.


Pacificklaus sez: Often success in underwater photography hinges on little things. If your strobe batteries run out halfway through the dive, no matter what amazing marine life and natural history will unfold in front of your lens, you will not get any pictures of it!


Doctore Strobe at work.