Please explain Eneloop to me!

[benhar]

Seems that I continue to suffer from "not knowing what I don't know"...

So what's the deal with Eneloops? I had pretty much decided to buy a Quark AA2, since AA is the most common battery in my house and I have at least 8 rechargable Energizers. I like the performance of CR123s better, but I was going for convenience and battery availability.
But it seems pretty much assumed around here that Eneloops should be used. In fact, I've even seen it hinted that you shouldn't use standard AAs when in high mode. Or have I missed something? The problem is, I would have to by eneloops and a charger, nearly defeating my purpose of getting a AA flashlight over a CR123...

(Note: tried searching a little, but eneloop is a common word around here)

 

[oldpal]

Eneloops are low-self discharge NiMH rechargeable batteries made/sold by Sanyo. They keep their charge while not in use much longer than standard NiMHs. Check out the other CPF forum on batteries at http://www.candlepowerforums.com/vb/forumdisplay.php?f=9

Hugh

 

[SilentK]

They also tend to have a pretty flat discharge curve, and last much longer in things such as flashlights. They also support what we call the "guilt free lumens concept"

 

[benhar]

Didn't even see that there is a battery forum

So, it doesn't hurt anything to run the flashlights on high/turbo/etc with standard alkalines? I'll still probably get some eneloops, but that would at least let me retain the benefit of having an AA flashlight.

 

[Marduke]

It won't hurt to use alks, but the performance will suck a big one.

 

[WadeF]

You risk ruining a high end flashlight by using cheap akaline cells as they can leak. Eneloops shouldn't leak and they will provide better performance. The nice thing is if you are in a pinch and you can't charge your Eneloops you could put regular akaline AA's in there. I would just avoid storing it or keeping akaline AA's in your flashlight for any longer than needed.

I keep a Fenix TK20 in my van all year and the temp in there can range from sub freezing to well over 100F in the summer. That would be bad environment for akalines so I go with the Energizer lithium AA's as they perform well in very cold temps and shouldn't leak. This is set up as an emergency light that is used infrequently.

The Eneloops are great if you will use the light frequently so you won't be buying batteries all the time.

 

[DM51]

Moving this to the Batteries section...

 

[kramer5150]

Alkalines will leak and ruin whatever they are installed in, if left unattended. They will "work"... you just have to check them *frequently* for leaks. I have had new as well as used alkalines leak. My last one (a new cell) was sitting on my PC keyboard and leaked all over, stripped some of the paint off.

Eneloops are lower capacity than many other NiMH cells but do not suffer from self discharge. Another member PM'd me and said it has to do with the physical spacing between the anode and cathode inside the cell. Eneloops have a smaller anode/cathode plate area, but greater distance separation between the two... and thus the plates hold their electron charge much better than ~2700-3000 mah cells. The latter having a more densly packed anode/cathode construction.

I use 2450 mah energizerNiMH cells and top them off every other week. So I am not really stressing their ability to hold a charge. (pic below) Either way... Eneloop or otherwise, NIMH is far and away a better (safer) chemistry than alkaline... IMHO.

I also have eneloops but I only use those in the Wii remotes.

**edit**
Apparently I don't learn very well... you can see a Kirkland Alkaline cell (re-branded Duracell) sitting on top of my keyboard in the pic above.... LOL

 

[benhar]

That looks like the same Energizer rechargables I use, so I guess I'm OK!

 

[kramer5150]

That looks like the same Energizer rechargables I use, so I guess I'm OK!

Well.... so far mine have been OK. these cells are only 2-3 weeks old. I haven't read many complaints about the 2450 cells, so I went for it. From what I gather, the 2500 cells however are a general thumbs down (forum consensus).

 

[Marduke]

Just don't use Energizer 2500's.

 

[wapkil]

Eneloops are lower capacity but do not suffer from self discharge. Another member PM'd me and said it has to do with the physical spacing between the anode and cathode inside the cell. Eneloops have a smaller anode/cathode plate area, but greater distance separation between the two... and thus the plates hold their electron charge much better than ~2700-3000 mah cells. The latter having a more densly packed anode/cathode construction.

I use 2450 mah energizerNiMH cells and top them off every other week. So I am not really stressing their LSD characteristics. (pic below) Either way... Eneloop or otherwise, NIMH is far and away a better (safer) chemistry than alkaline... IMHO.

I'm not sure what you mean, but I think that these Energizers are regular, non-LSD NiMH cells. If they are, they don't have any "LSD characteristics", as we normally understand them.

From what I read, the main difference making Eneloops able to discharge slower than regular NiMHs is caused by changes in the cathode alloy (elimination of Co and Mn). There are other minor differences but this difference in chemistry is the most important. If the battery doesn't incorporate it, it is an non-LSD NiMH. It may self-discharge somehow slower than higher capacity cells but definitely not as slow as LSDs.

 

[travelinman]

I have read reports that the eneloop type (low self discharge) battery is also made to much higher tolerances and far higher quality control than regular NiMH cells, thus having much lower (but not zero) self discharge rates.

There are lots of cells out there that are just rebranded eneloops, such as the white Superstore brand sold here in Canada.

You don't need a different charger for them, as far as I know. I use a couple of different chargers and they work equally well with low self discharge (LSD?? not such a good acronym I guess but then I'm a child of the 50's) cells.

 

[4x4dodge]

The new Duracell pre-charged bateries are Eneloop rebrands. Same cell construction, both made in Japan, just different labels. I use these since they are much easier to find locally.

My favorite cell is the new 8X Enegizer Ultimate Lithium. Even my TK40 is very lightweight with 8 cells, plus they last forever...

 

[vali]

Sometimes an image can show you things that will otherways need a lot of words. From the capacity and peformance point o view just check the runtime graphs in the following threads:

1xAA reviews
2xAA reviews

As you can see the alkalines chamistry cant sustain the high discharge flashlights need in HIGH levels. The performance is poor and the capacity is low (capacity is different at different discharge rates). Eneloops are rated at 2000 mAh and alkalines are tipically in the range or 3000 mAh (IIRC, correct me if I am wrong).

On the other hand Ni-MH can sustain that kind of discharge and the capacity doesnt suffer compared with alkies, so you will find a 2000 rated NiMH battery have more capacity than a 3000 rated alkaline.

Ok thats great and NiMH are "thabomb", but they have some drawbacks. Regular NiMH cells lose charge across the time, faster as the cell ages. If you charge some cells and store them, when you need to use them, they will probably be discharged. LSD batteries (LSD = Low Self Discharge) can hold their charge for months (but have lower capacity), thats the reason most people recommend eneloops. Is like having an alkaline cell that can support high discharge, you can recharge and dont lose (too much) energy when stored.

The only (basic) requisites to enjoy your rechargeable cells is to have a decent charger and dont mix different capacity batteries. For decent charger I mean a "smart" charger (those who can know where the battery is full) with individual charging slots.

 

[benhar]

OK, so the bottom line is that the main differences come in to play when they are not in use, though the eneloops may offer longer and steadier performance in the light.

On a side note, I like that review on the 2xAAs. It would be nice to see an update with the Quark included! I've been curious about how well the Quarks throw compared to the TK20 and P100A2.

 

[LuxLuthor]

I don't know why people cannot do a little looking before assuming CPF is a chat room. There is an incredible amount of useful information that has already been posted about these cells that you miss by starting another topic.

 

[vali]

Bottom line is alkalines are weak and prone to leak. NiMH can sustain the drain whathever their type and LSD can be stored charged and be usefull, whereas regular NiMH will need to be charged just before their use.

Be sure you have a decent charger and you will be happy with NiMH.

 

[benhar]

I don't know why people cannot do a little looking before assuming CPF is a chat room. There is an incredible amount of useful information that has already been posted about these cells that you miss by starting another topic.

That was a little unnecessary. The thread went a little off from what I intended and became a generic answer, but my primary question was the peformance of enloops in the flashlights. Looking at the hits in that link, I didn't see that.

I may be new to these forums, but I'm not such a complete idiot that I can't search. I didn't see anything initially that answered my question, and I don't have an hour to spend looking through all the threads. This may not be a chat room, but it is a forum, where people shouldn't be afraid to post a new topic without being hammered.

 

[benhar]

Just don't use Energizer 2500's.

Got home and checked, that's what I have