Rechargeable Battery Packs?

[bobandcompany]

Has anyone here made a rechargeable battery pack for their light or camera? I was wondering after seeing the price of NiMH batteries down so low. I am interested in making a battery pack for my UK C8 light and I ahve no idea about how to go about it. I have found 8 C cell 4500mAh batteries for about $40 shipped. In energizers that is about 6 dives. Would I be better off using rechargeable C cell batteries?


www.bydusa.com is where they have the batteries.

 

[Scubaroo]

Until I got my canister light, I used 8 NiMH C cells in my Shockwave (similar to your C8 light). They worked fine, and I haven't had to buy batteries since. They are also a lot more environmentally friendly than tossing out used alkaline batteries every month or so (depending how often you dive). Just make sure you recycle them in a thousand charges or so

My understanding is that NiMH batteries last longer than NiCad batteries.

I don't know if it is worth the trouble of trying to make up a battery pack, although it's somewhat straightforward to do. You would need to be sure that the batteries are in the correct configuration so that all of the contacts connect (probably a straightforward square stack of batteries, two layers of four). Load the individual batteries into the light to see if they are tightly packed, then it might be possible. Making a battery pack would require a different charger that is capable of charging the pack.

Also make sure you get the correct batteries - there are flat top batteries designed for use in battery packs, and nipple top batteries designed for loose usage in a battery compartment. They're generally not interchangeable.

Ben

 

[scorpionfish]

I have used NiCad rechargeables for my camera and my Sea & Sea strobes for over a year. I followed the advice of Norbert Wu in one of his books on U/W photography: Radio Shack batteries and charger.

However, I read somewhere that use of NiMH batteries is a potential problem at depth due to the potential for hydrogen generation. I must confess that I have not followed up and discovered what the chemistry is that would produce hydrogen from a NiMH battery, though.

At any rate, I have discovered three things in the course of using these rechargeables:

(1) They recharge slowly and, so, a couple of rechargers is nice.

(2) In exotic climes you may need to bring a voltage converter and, if you have two chargers, you will need two converters (sorry for stating the obvious).

(3) I try to keep close track of battery usage to avoid having to use the charger unnecessarily. However, if it is not being used I tend to toss in a few batteries. I am not at all certain if this truly affects ultimate battery lifetime because I have had conflicting advice.

If I get inspired, I will check into the hydrogen generation problem and get back to you.

Scorpionfish

 

[k4sdi]

scorpionfish once bubbled...

However, I read somewhere that use of NiMH batteries is a potential problem at depth due to the potential for hydrogen generation. I must confess that I have not followed up and discovered what the chemistry is that would produce hydrogen from a NiMH battery, though.

Umm, correct me if i'm wrong here (and I usually am) but if the batts are in a sealed case, are they not still at 1 atmosphere? Hopefully they would not have water in there either (which I could see causeing a problem, be it hydrogen gas or not)
Just my strange and random thoughts.....................

Mark

BTW NiMH Rocks!

 

[cpalerm]

I don't have a full answer, but here is a quote from the operating and maintenance instructions of my shockwave II:

Note: Some battery formulations can emit hydrogen gas. This gas can create an explosion potential in sealed devices if not vented or removed. Your light is equipped with a platinum catalyst that will remove this gas. When replacing batteries, visually inspect reflector assembly for broken or missing catalyst. If catalyst appears to be damaged or the light has flooded, replace the catalyst assembly before using.


What this formulation is, I do not know; but their lights come with alkaline batteries, and their rechargable sets use NiCd.

Cesar