Questions from Lithium-ion noob - should I replace my Eneloops?

[tychoseven]

Currently all my lights run on AAA or AA batteries. I have Eneloops and a Maha C9000 for charging them. I'm thinking of getting into Lithium-ion rechargeable because it'll expand the types of lights I can get. I'm wondering if I will get better runtimes if I were to replace my Eneloops with 14500s in lights that support them? It looks to me like most 14500s are 3x the voltage, but 1/3 the capacity of a AA Eneloop....not sure what that means for runtimes.

Ideally I'd like to get only one charger for all my L-I needs. I'd like to use 10440, 14500, 16340, and 18650 batteries. Will the Pila IBC work with all those? 10400 and 16340 are not mentioned as being supported sizes. Is there a good charger that will do them all?

 

[mvyrmnd]

It's fairly dependent on the driver in each light, but the Li-Ion will provide more watt-hours than NiMH, meaning longer runtimes.

Eneloop-1.2V and 2000mAh = 2.4Wh

Li-Ion 14500 - 3.7v and 900mAh = 3.33Wh.

 

[Norm]

It's fairly dependent on the driver in each light, but the Li-Ion will provide more watt-hours than NiMH, meaning longer runtimes.

Eneloop-1.2V and 2000mAh = 2.4Wh

Li-Ion 14500 - 3.7v and 900mAh = 3.33Wh.

Not too many 14500's will make 900mAh though Simon, cheap Chinese cells may only be half of that figure.

Norm

 

[mvyrmnd]

Not too many 14500's will make 900mAh though Simon, cheap Chinese cells may only be half of that figure.

Norm

Well, the OP should buy good ones then :poke:

Buy AW 14500's. They'll actually give the value on the sticker, and they won't explode and maim your dog.

 

[hellokitty[hk]]

IMO at this size NiMH is simply better and more simple.

 

[sassaquin]

Ideally I'd like to get only one charger for all my L-I needs. I'd like to use 10440, 14500, 16340, and 18650 batteries. Will the Pila IBC work with all those? 10400 and 16340 are not mentioned as being supported sizes. Is there a good charger that will do them all?

Before you get into rechargable lithium-ion batteries, educate yourself on the special care they require and how dangerous they can be if not handled properly. Research information here and also at batteryuniversity.com before buying anything.

I don't own a Pila, but have read it is the best 18650 charger and can charge different sizes with spacers and/or adapters.
Check out Cottonpickers World Smallest Li-ion Charger being sold on The Marketplace. They are hand built in the UK and will charge just about every size li-ion. Cottonpickers is a pleasure to do business with and offers excellent customer service. I own several versions of his chargers and they all have worked flawlessly.

 

[snakyjake]

Safety is my main concern with Li-Ion. Explosions can be caused by under charging, over charging, or running multiple cells of unmatched voltage. I'm mostly concerned about running the batteries down until the protection cutoff, hoping the circuit doesn't fail.

I caution you about reading any li-ion deemed "safe chemistry", as that word hasn't really been defined in the context of flashlights.

I don't think you get much of an advantage with li-ion with today's flashlights, and I'm on the fence if they are worth the explosion risk.

Jake

 

[TEEJ]

The "explosion risk" is, statistically, pretty much limited to cheap junk batteries and chargers, and to a lack of proper handling/maintenance, such as not matching multi-celled applications.

If you get good cells, and charge them properly...you can get more potential power and run time than on primaries or Ni-MH, etc.

If you'd buy chinese knock-offs and so forth, sure, you're asking for trouble/to be a statistic.

Personally, the only batteries I've ever had that were a problem were alklines...never with any of the others.

 

[degarb]

2000 milliamps is not for me. I been buying eneloop pro and sanyo 2700s. I got some free/cheap eneloops from Biglots, recently, I admit, with a smart close out charger.So, the true number comparison should be:1.2 volt x 2700 milliamp Sanyo NIMH = 3.24 wh for NIMH v 3.33 WH for a liionSo, volumically, not much diff. between nNIMH and LiIon on smaller cells like 14500 or 123. Not sure about weight, or how energy density goes up with bigger cells like the 18650. Maybe the protedction takes up too much space on smaller cells.Also, I am waiting for expected better chemistry over next year for better capacities. Maybe.

 

[tychoseven]

Thanks everybody. I've definitely been doing research into into the proper handling and charging of Li-Ion rechargeables. After all the recommendations here I won't bother with anything but AW protected cells and a quality charger.

I'll be getting some Eneloop Pros in the near future for my Zebralight; perhaps that will provide me with the extra runtime I'm after.

So far there aren't any lights that I must have that I can't power on Eneloops; if that changes then I'll get some Li-Ions. But it sounds like they aren't a replacement for NiMH, but a supplement/different animal.

 

[Joe Talmadge]

Yes, for me, not a replacement for NiMH. For me, I have a huge number of Eneloops, and besides flashlights, I power everything in the house that can take AAA or AA with them -- all my remote controls, clocks, etc. With Li Ions, I basically have as many batteries as I have flashlights that I carry often that use them. I don't want my Li Ions to get lost in a drawer and sit for years, I don't want me Li Ions to get put in a flashlight that gets forgotten. Eneloop is great for everything, and buy a bunch of extra to keep charged and used whenever. For me, Li Ion is great for special applications, and I am more careful about inventory control, making sure batteries never sit around long at full charge, etc.

 

[RBWNY]

Thanks everybody. I've definitely been doing research into into the proper handling and charging of Li-Ion rechargeables. After all the recommendations here I won't bother with anything but AW protected cells and a quality charger.

So far there aren't any lights that I must have that I can't power on Eneloops; if that changes then I'll get some Li-Ions. But it sounds like they aren't a replacement for NiMH, but a supplement/different animal.

As far as leaping into Li-ion goes. Unless your AA lights can handle the extra volts, and for safety purposes, as long as they're only used in single-cell applications, and unless the light gives you a boost in brightness w/a 14500, you'd probably be better to wait until you have some 18650 lights. With a 14500, you'll be charging them quite frequently, and again, in MOST cases, if there IS a difference in lumens, it may not be that noticeable. When you DO go in that direction, I'd suggest either the Pila, or the 4sevens Single Bay Charger. Pila requires extra spacers for 16340... 4sevens doesn't.

 

[fyrstormer]

The dangers of lithium-ion batteries are real, but so are the dangers of driving a car full of explosive gasoline. Li-Ion technology has advanced far enough that the necessary safety measures are integrated into all but the cheapest designs. Good chargers limit the charging current and terminate at the right voltage, and good batteries have low-voltage-cutoff circuits that can be used as a primary cutoff mechanism without any risk of damage. I've "bottomed-out" my AW Li-Ion cells on a regular basis for years and never once had a cell refuse to recharge, to say nothing of exploding.

Personally I think the 123 form factor is better for Li-Ion batteries. The extra 2mm of width is not significant in real-world use, the 16mm shorter length is definitely more convenient unless you have bear-paw hands, and the different shape means you won't mix up your batteries. (you only have to put a pair of 14500s into a 2xAA light one time to learn that lesson, but your kids might have to break more than one light before they understand, though.) Also, the 123 form factor is available in a single-use cell, whereas the 14500 form factor isn't. (yes, there are AA batteries, but they have a third the voltage of a fully-charged RCR123.)

 

[HKJ]

The advantage to 14500 size is the slightly larger capacity*, you can also get lights that can work with a single cell of either alkaline, NiMH or LiIon.
My favorite LiIon battery is the 18650.

*I have just been testing one that hold 800mAh at 1A and 780mAh at 2A.

 

[Wrend]

http://www.candlepowerforums.com/vb/showthread.php?333381-3-AA-in-series-vs-3-14500-in-parallel

This thread has some relevant information in it, and my general point of view.