Rechargeable Batteries for Dive Lights

[dlegros]

Never had a problem with Li-Ion myself.

Currently diving with a Salvo 21W HID and Li-Ion pack.

The possibility of Hydrogen off-gassing is a recharging problem.

Dom

 

[Bill51]

Most camcorders use Li-Ion and we seal them up in housings all the time without any problems.

 

[Matt S.]

Li-ion definitely has a better self-discharge rate than NiMH. The downside is if a Li-ion battery ever goes completely dead it loses some capacity permanently. (Gadgets that are made to use these batteries are supposed to be smart enough to stop draining the battery when it hits a certain point.)

They make chargers that are designed to keep batteries topped off, so you can leave them in until you need them. Handy.

 

[havnmonkey]

Righto... gas release while recharging!

 

[MoonWrasse]

Good to hear there's no problem using rechargables with the HIDs, especially the UK
as I'm considering buying one but was worried that it wouldn't work well due to the lower voltage of the rechargable.
Been there before.

 

[CompuDude]

Good to hear there's no problem using rechargables with the HIDs, especially the UK as I'm considering buying one but was worried that it wouldn't work well due to the lower voltage of the rechargable.
Been there before.

I wouldn't use NiCad rechargeables, but NiMH rechargeables are much better.

The voltage output of alkalines drops off the rated peak shortly after first use. You only get the full voltage for the first few minutes, actually, then it drops down to a lower voltage that progressively drops. One advantage to NiMH rechargeables is the steadier voltage output. It starts off slightly lower, but stays at that level in a very stable way until the battery is nearly exhausted. You will actually get better, more consistent output from NiMH over alkalines. You'll get a longer burn time, too, as the capacity is much higher.

Really, the only downsides are the self-discharge rate (and corresponding lower shelf life between charges) and the initial cost.

 

[beezwax]

I use rechargeables in my Light Cannon, I think I got 8 C cells and a recharger for less than $60. I just checked the pricing on amazon for what I have, it is now:

Rayovac C cell 2200mAh NiMH 2-pack, $10 (x4)
Rayovac Universal Charger $18

I highly recommend this kit. The charger will work for AA, AAA, C, D, and 9volt, and it will recharge Alkaline, NiCd, and NiMH.

When you consider that you'll spend around $10 a pop for a set of disposables, it's obvious that you don't have to do too many dives before the rechargeables pay for themselves (even if you get 2-3 dives out of a set of disposables). With these numbers if you use your light on more than a dozen dives a year you're past the price break, and that's not even considering the additional savings if you use the charger for other battery sizes as well.

 

[CompuDude]

For the record, the Accupower batteries I'm using cost $15/2-pack compared to your $10/2-pack, but they are 6000mAh batteries instead of the 2200mAh Rayovacs you have.

 

[MoonWrasse]

For the record, the Accupower batteries I'm using cost $15/2-pack compared to your $10/2-pack, but they are 6000mAh batteries instead of the 2200mAh Rayovacs you have.

But what recharger are you using?

BTW, yes that's true about the falloff curve for rechargables -vs- alkies, however some devices don't tollerate the lower 1.2 voltage most rechargables deliver. Over 8 batteries that's a 2.4V difference.
On the other hand, some devices like my old Kodak camera doesn't like Alkies very much due to the curve.

Also the UK site of the HID lists NiMH or Nicad Cells, but not Lion batteries.
http://www.uwkinetics.com/products/detail.php?ProductID=5&cat=6

 

[dlegros]

If you are taking an existing light (such as a UK) and putting cells in, I would use NiMH.

LiIon primary cells need to be looked after carefully. The Salvo pack has a protection circuit built in to prevent over-charging and over-discharging.

Dom