Some Eneloop Questions

[Albinoni]

I'm seriously thinking of purchasing a pack of these AAA and AA batteries for my torches (Minimag LED AA) and (Led Lenser Hocus Focus 7438 AAA).

1. Whats the best charger to use for the Eneloop batt, is it best to stick to
the Eneloop charger itself

2. Does the battery need to be fully depleted before its recharged ?
3. On a full charge and only used now and again how long on average will
it last before I need to recharge?

4. Whats the reccomended time for the first charge and should that charge be the same as the 2nd 3rd, 4th etc charges?

5. Once the batts are fully charged is there some sort of protection
circuit in the charger to cut it off ?

6. On a full charge do Eneloops actually have a longer run time; i.e last
longer than that of Alkalines ?

 

[SafetyBob]

Try doing a "eneloop" search here on CPF. But first, check out my similar question about eneloops awhile back. It should give you someplace to start.

http://www.candlepowerforums.com/vb/showthread.php?t=182527

Bottom line from what I can tell is eneloop charger is OK. If you have a nice charger from the RC world (that give exceptional control and options) so much the better. The Triton2 that I have was the best investment towards batteries I have ever made. The only bad part about a RC type charger is that you will either have to charge batteries for wife/family or teach them how/what to do.

Go back about two weeks ago and start looking for the eneloop questions that popped up. There was some great knowledge that was given, but I can't find it right off hand but will look some more.

Bob E.

 

[SilverFox]

Hello Albinoni,

The battery manufacturers recommend charging NiMh cells at a rate that completes the charge in 1 - 2 hours. For the Eneloop cells, that would be a charger that charges in the 1 - 2 amp range.

The other recommended charging rate is a timed 16 hour charge at 0.1C. 0.1C for the 2000 mAh Eneloop cells would be 200 mA.

The Eneloop charger does not charge at either of these charge rates, and it is under study. While some people have been using it without problems, it does not charge within the recommended rates. It could be utilizing a different end of charge signal, but as I mentioned earlier, we really don't know what it does.

To answer your #2 question... No.

How long a cell lasts is dependent on a variety of things. You have to know the draw at the cell, and how long the light is used. With this information you can go to the NiMh Shoot Out thread and review the available capacities at your specific load. Dividing the capacity by the load will give you how long it should last.

Initially, two years ago when the Eneloop cells first came out, we found little benefit in forming the cells and the recommendation was simply to charge and use them. Now the cells have aged a little, and there seems to be some benefit from doing the standard forming charge. This is charging at 200 mA for 16 hours.

After that you are back to normal charging as explained earlier.

"Smart" chargers utilize a end of charge signal detection, then back that up with a safety timer in case the signal is missed. In addition, chargers utilize a maximum cell temperature shut off. Some chargers do this better than other chargers. You can have a look at the Charger Shoot Out thread to see some comparisons. It is not complete, but reading through it should give you some idea of what questions to ask.

Your final question is dependent on load. With low loads, Alkaline cells will last longer, but they can not be recharged. With higher loads, the Eneloop cells will last longer.

Tom