Rechargeable Batteries for Dive Lights

[divebrasil]

Hi, does anybody use rechargeable batteries on your lights?

I got a UK Sunlight C8 that requires 8 C batteries. I am figuring it will cost a lot if I have to replace 8 C batteties after, let's say, 3 dives. So I am thinking of getting rechargeables and a charger. I am guessing they will most likely be NiMH.

Do you guys have any suggestions as far as brands or where to buy then?

Thanks

 

[divebrasil]

Another thing I not sure is if Li-Ion battery would actually be better than NiMH for dive lights, since NiMH have high discharge rate.

 

[CompuDude]

I have been using rechargeable C cells from AccuPower (6000mah) in my UK Light Canon HID.

Pick them up from: http://www.thomas-distributing.com/cbatteries.php

 

[NorthernShrinkage]

Although the rechargeables are nice and definetly more enviromentaly friendly If you sit down and do the math Disposables are the cheaper way to go . I have used Rayovac duracell and energizer rechargeable batteries . The best I have gotten out of them is 2 years use before they start going south . I generaly get 4 dives or close to 4 hrs on a set of dispoables . I figured it out a year ago and rechargeables were costing me more money basicly 8 high quality rechargeables ran me about 80 dollars plus and the charger was about the same cost a box of 48 duracells was about 25 so I swiched back.

Just my 2C

 

[rakkis]

Although the rechargeables are nice and definetly more enviromentaly friendly If you sit down and do the math

It really depends on your diving frequency. Rechargeables work out better when you're going out often.

 

[CompuDude]

Although the rechargeables are nice and definetly more enviromentaly friendly If you sit down and do the math Disposables are the cheaper way to go . I have used Rayovac duracell and energizer rechargeable batteries . The best I have gotten out of them is 2 years use before they start going south . I generaly get 4 dives or close to 4 hrs on a set of dispoables . I figured it out a year ago and rechargeables were costing me more money basicly 8 high quality rechargeables ran me about 80 dollars plus and the charger was about the same cost a box of 48 duracells was about 25 so I swiched back.

The difference is you can top off your rechargeables everytime you go out diving, and not have to wonder how much charge you have left in the seet of alkalines, and if you did one dive or two on it already, and if perhaps you would be safer to throw away a full set of batteries that was only used for 20 minutes just because you can't recall for sure.

Top them up before each dive day, and you're always starting off with a fresh set of batteries.

Also, good rechargeables hold a lot more juice than alkalines, and will give you more burn time.

You're also including the cost of the charger in your calculations, which ignores the fact that your charger can be used to charge batteries for a variety of devices for longer than the life of the batteries themselves. If you keep your rechargeables long enough, chances are you're still going to have devices that use C cells (for instance) once that first set of rechargeables is dead, and you'll then be able to amortize the cost of that charger across yet another set of batteries.

But the big thing for me is always knowing I am starting my dive with fresh batteries, instead of wondering how much time I have left on the set I left in from last time.

 

[divebrasil]

CompuDude, do you need 8 C batts? So do you charge 2 batches of 4?

The one thing about the NiMH is that they have a high discharge rate, so if you charge today, and use it a week from now, they might be half discharged.

So, now I am wondering if the Li-Ions would be better?

Not sure

Thanks

 

[CompuDude]

CompuDude, do you need 8 C batts? So do you charge 2 batches of 4?

The one thing about the NiMH is that they have a high discharge rate, so if you charge today, and use it a week from now, they might be half discharged.

So, now I am wondering if the Li-Ions would be better?

I actually decided to buy the bigger 8-cell charger, so no, I charge all 8 batteries at once. Most other people I know do two charging cycles with 4-cell chargers, however, or buy two 4-cell chargers.

Very true about the high discharge rate. But then, it's not exactly difficult to top off your batteries the night before a dive. And while the self-discharge rate is high, it's not 50% over a week. I don't think I would want to go much over a week without using them, however, else I'd want to recharge. Again, recharging is not exactly a "problem", unless you are on an extended trip in the middle of nowhere without power. And then I would want to bring in a truckload of alkalines anyway.

I don't know if Li-Ion is better or not, but I'd stick with the known quantity of the NiMH systems for now. I vaguely recall some issue with Li-Ion producing hydrogen while discharging so it needs a special absorption system to run underwater without blowing up? Could be wrong on that, but I recall reading something to that effect about rechargeables at one point when I was trying to decide between the two. May or may not have been a deciding issue however.

 

[ReefHound]

I figured it out a year ago and rechargeables were costing me more money basicly 8 high quality rechargeables ran me about 80 dollars plus and the charger was about the same cost a box of 48 duracells was about 25 so I swiched back.

Just my 2C

You can get 8 C-size rechargeable Energizers on Ebay right now for $35, $55 with charger.

On the other hand, I've found C size the most costly for rechargeables. On the more popular AA size the rechargeables are cheap and definitely the way to go.

 

[havnmonkey]

I think the Li-ion release more gas... problematic in an o-ring sealed container. Nimh rechargeables for primary light, alkaline for back up...