Rechargable batt options for Hollis LED3 & mini3

caveeagle

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I have 5 divers in the family and we do mostly Spring/Cavern/Cave diving at this point. I was looking for a good option for cavern primary lights with push-button switches and found a good deal on some Hollis LED lights locally. I got a couple of there LED3 lights that run on 3x AA batteries and an LED Mini3 that runs on three AAA batteries.

I was hoping that I could get the spacers to put an 18650 light in them (like on my Dive Rite BX-1 backups), but that does not seem like it will work do to the body length.

In any case, Anyone want to inform me (or speculate) on the best option to put rechargeable batteries into these lights? I have heard good things about the Eneloop batteries, but was not sure if they would keep the same 1.5v/cell and suitable for an LED flashlight.

FYI:
the Hollis LED3 runs a Cree LED R5 with an output of 900mA
the Hollis Mini3 runs the same Cree LED R5 but with an output of 700mA
 

DIWdiver

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Eneloops certainly are good batteries, and they will actually hold voltage better than alkalines.

An AA battery is the same size as a 14500 lithium cell. 18650s will definitely not fit that light, as they are fatter and longer. I think you'll get a lot more runtime out of Eneloops than 14500's, unless you can figure out how to run 3 in parallel in that light.
 

caveeagle

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Eneloops certainly are good batteries, and they will actually hold voltage better than alkalines.

An AA battery is the same size as a 14500 lithium cell. 18650s will definitely not fit that light, as they are fatter and longer. I think you'll get a lot more runtime out of Eneloops than 14500's, unless you can figure out how to run 3 in parallel in that light.

Keep in mind, both these lights use 3 cells that bundle into a holder and slides into the body as if it were one large battery. So The LED3 essentially runs on a 4.5v battery pack made up from 3 AA batteries. In the case of my Dive Rite BX-1 Lights, a delrin sleeve/spacer is included that allows you to run a single 18650 battery in the place of the bundled AAA batteries.

So maybe I am now confusing the question by comparing my new Hollis lights to the other Dive Rite lights,

But it sounds like the Eneloops will get the job done.

Any thoughts on the Eneloop Pro (black) batteries? For my purposes, I like to have at least two sets of rechargeables on hand so I can swap in fresh batteries on my primary lights between dives.
 

caveeagle

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Does anyone know if I will loose brightness using the Eneloop batteries vs the alkaline batteries? I don't seem to see the voltage posted for the Eneloop or E Pro batteries But I assumed they were 1.2v like the other NmH batteries I see.

It might be ok if they hold the peak voltage longer than alkaline, but I was hoping to find a battery option that would be at least as bright as the 3xAA alkalines combo.
 

DIWdiver

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I think you'll be happier with eneloops than alkaline. Alkalines may start at 1.5V, but they rapidly drop to 1.2-1.3V under load, and continue down from there. Eneloops should hold 1.25V pretty well under moderate load.

I looked at the Pros about a year ago, and decided they weren't worth the extra money. If the price is closer now, maybe they are. I think the primary difference is capacity.
 

caveeagle

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The cost for the Eneloop Pro does not seem to bad, but they are rated for only 500 recharge cycles. For dive lights, I suspect, I would be more than happy to get the 500 cycles out of them, but my concern is keeping track of how may cycles each one has had. For cave diving, most of these batteries will be used in back-up lights and (hopefully) not used on most dives. So I would need to have a process to make sure fresh good charge before each dive trip.

Back in the early 90's, I would write dates on my alkaline batteries with a sharpie and just cycle in a fresh set every so often. These lights only got tested with a quick on/off before each dive. The 'used' batteries would just get put into the drawer for household use after several dives or a month or two of non-use.

Now with the newer rechargables, I am thinking through how to best maintain and keep up with them.
 
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