# Lithium batteries versus NiMH



## dbsoccer (Mar 30, 2009)

Into some new territory for me so be kind. I need a brand recommendation for a AA battery for a digital camera.


----------



## LouRoy (Mar 30, 2009)

That's an easy one. Just get some Eneloops (low self-discharge NiMh). 
And welcome to CPF! :wave:


----------



## Russel (Mar 30, 2009)

dbsoccer said:


> Into some new territory for me so be kind. I need a brand recommendation for a AA battery for a digital camera.



Are you trying to decide between primary and rechargeable batteries?

[edit]If you are looking for rechargeable batteries, I'll second LouRoy's recommendation: Eneloop AA cells.[end edit]


----------



## dbsoccer (Mar 30, 2009)

Thank you for the quick response. I have 2900mAh Powerex that I tried in the camera but they seemed to drain pretty quickly. I bought some non-rechargable Lithiums that were 'for digital cameras' and they seem to be holding up. Pretty expensive when you have to buy them at Disneyland. I thought maybe a rechargable Lithium would be better than a NiMH.


----------



## 1dash1 (Mar 30, 2009)

*IMO...*
*Best all-round use: Eneloops (2000 mah)*
*Low self-discharge, retains 85% of rated capacity after 1 year.*

*Best high-capacity use: Powerex (2700 mah)*
*Moderately low self-discharge, retains 85% of rated capacity after 3 months.* 

_Comments..._

_If you don't need the extra capacity, you can't go wrong by purchasing Eneloops. If you do need the extra capacity, I'd suggest your first option would be to carry spare batteries (again, Eneloops). Remember, it was only a few years ago when most rechargeable AA's were only 1000-1400 mah, so the 2000 mah Eneloops are no slouch!_

_As for the Powerex 2700's: There have been some reports of performance degradation after two years or after a large number of recharge cycles. Personally, I haven't seen any loss of power in my 3 year-old Powerex 2700's, but they've only seen a few dozen recharge cycles. I cannot attest to what happens after 100 or 200 cycles. I'm also presently experimenting with Sanyo 2700's and they seem to be performing on par with the Powerex 2700's. Unfortunately, there is no cost savings in using the Sanyo 2700's, so I'd recommend that you stick to the Powerex brand if you are looking for high capacity cells._

EDIT: I'm not familiar with the Maha 2900 cells that you referred to. 

As to rechargeable lithiums, they run 3.7 volts nominal (4.2 volts hot off the charger). They would damage your camera or flashlight if you did a straight substitution for the alkaline, lithium e2, or NiMH AA cells.


----------



## kay188 (Mar 31, 2009)

My take on it would be that it depends how frequently you use your camera, and how MUCH it stays on. (I think I just repeated myself)

1. If you take A LOT of pictures (with or without flash), meaning your camera would be on for a LONG period of time, during the day, then get high capacity batteries.
The Duracell 2650's are almost as good as the Sanyo 2700's, according to the NiMH shoot out charts that's posted on this forum.
Then at night, you can just charge the cells and have them ready for the morning.
_
I personally use Duracell 2650's from time to time for constant on items, and they last VERY long._

2. If you don't keep your camera ON for a very long time, and turn it on only to take your pictures and then you turn it off put it away, until your next need for the camera again, then I would suggest Eneloops/Duraloops.
As your camera does not stay on for a LONG time, the batteries will retain the charge longer than standard NiMH's.
So you could probably go 2 days without a charge, of course depends on how you use your camera.

I hope you get my take on it. Haha.

So to summarize: 
Get high capacity if you have a constant ON device.
Get LSD (Eneloops), if you dont use your device as much, and you turn it off here and there.

As 1dash1 said, for a device that uses AA batteries, you cannot put Lithium Ion AA's in. The voltage is way too high, and you'll damage your device. Li-Ion is used only in select devices where it's designed for it, such as camera's with a proprietary battery.

You can use Energizer Lithium AA's however. Since they're primary batteries and they give out proper AA 1.5 volts.


----------



## Sub_Umbra (Mar 31, 2009)

FWIW NiMH cells have a longer *service* life -- asuming a good charger is used. Secondary lithium batteries begin to deteriorate *at their time of manufacture* -- whether they are in use or in a warehouse. After two years the degradation is measurable. After three years it is noticable to most. Beyond that most will have to look for replacements.

These factors are not important to many but they are absolute *deal killers* to many.


----------



## vali (Mar 31, 2009)

Im not an expert in batteries but here is some considerations:

Keep in mind that there are 2 big types of lithium batteries, primaries (non rechargeable) and rechargeable (and within this type there are several types, but I will refer them as a bulk).

Primary lithiums have simmilar voltage than alkaline cells and can be used roughly as a replacement (read the manual, the voltage is similar but a bit higher and if you use it multi-cell configurations the sum can be too much and fry the electronics). The shelf life of this type is very long (more than 10 years), have larger capacity than alkalines and support higher drain applications. Remember, normal alkalines have about 2500-3000 mAh when used at about 200 mA but about half that capacity when used at 1A (It's an estimation IIRC, the gurus can give you more accurate values). This is the reason you got a bigger "runtime" in your camera. The big drawback is price, as you already noted.

The lithium rechargeable ones are a different beast. Their voltage are way higher (3.7+ volts) and will burn your camera with almost 100% probability. You need to use specific chargers to recharge them and the number of cycles is lower than Ni-MH cells. Their life is low as stated in previous post and are expensive too. The pros are the amount of energy they can store and the higher drain they can support without capacity loss (compared with Ni-NH).

With Ni-MH you can find two types of cells too.

- "Normal" chemistry: Highest capacity between NI-MH ones. If you buy rechargeable cells you probably end buying one of these. The drawback is that they lose charge very fast when not used (this is known as "self discharge) and you need to recharge them just before use. The higher capacity, the faster the self discharge (roughly). Stay away from higher than 2500 mAh unless they are proved and tested reliable.

- LSD: The "new" Ni-MH. The capacity is a bit lower than the previous group and are a bit more expensive than "normal" ones, but they can hold it very well. About 15% loss in a year and in subsequent years they are tested to lose even less than this. You can find these as advertised as "Low self discharge", "ready to use" or "precharged". Sanyo eneloops are considered the best, but you can find some tests if you use the search. They are like having alkalines that can be recharged (with even an advantage, see below).

Both Ni-MH types are interchangeable in use (but do not mix them in a device) and have a voltage of 1.2 volts. Unless stated by the manufacturer you can use them as replacement for alkalines. Even if the alkalines stated 1.5 V this value will lower as you use them, so no worries about being less than 1.5 for the Ni-MH cells. The Ni-MH can support higher drain than alkalines with no lose of capacity and their performace is almost the same until almost depleted. If you overcharge them or discharge them too much (in multi-cell devices) you will ruin the batteries and will get short runtimes.

Digital cameras are tipically high drain devices and using akalines result in lower runtimes (again, akalines subjected to high drain use will have way lower capacity than lower drain use) than Ni-MH or Lithium primaries of lower capacty (unless the you have damaged or very old ones).

To resume:

If you want a "buy and use" way, without caring too much about cost, go for primary lithium.

If you want the best cost way, use Ni-MH and a decent charger to not damage the cells. Avoid those 15 min ones and "dumb" (timed) chargers. If you use the camera/device several times a week, get the higher capacity cells. If you use you devices from time to time but want to be ready to use, go for eneloops or similar.


----------



## lrp (Mar 31, 2009)

Great information here!!!


----------



## dbsoccer (Mar 31, 2009)

Great stuff!! My confusion was that I have one camera with a proprietary Li cell that seems to last forever. I have another camera that uses 4 AA cells. I tried a set of my 2700mAh Powerex cells (sorry for the 2900 typo) which seemed to drain very quickly. I use the Powerex in my bike headlamp very successfully. 

Recharging the day before is not an issue but if I'm in a hurry perhaps having a set of Li primaries or a set of Sanyo's Eneloops at the ready would be the way to go. If I have more time, then I can use my LaCrosse BC-900 charger to refresh as set of 2700 NiMH. 

A follow-on question: to retain cell life, we elected to turn the camera on and off over leaving it on. Is one type of cell better suited for reasons other than capacity for this type of use. Or is it recommended to leave the camera on and not cycle it. It was unclear why you'd select Eneloops over high capacity cells in one case and not the other.


----------



## Turbo Guy (Mar 31, 2009)

Eneloops and other LSD(low self discharge) AA NiMh have less capacity but they retain their charge extremely well during long periods of non use. Eneloops are also capable of delivering high discharge rates such as some digital cameras require.

Your Powerex 2700 cells should do well in your camera also but since you mentioned then work well in a light but not the camera I suspect they like mine have developed high IR (internal resistence). My 2700s are a few years old and their performance is rather dismal.I have cycled them several times but they will not hold their charge for more than a week. This is a somewhat common problem with very high capacity AA NiMH cells. The ones 2300 mAh and lower capacity usually have a longer service life.


----------



## cerbie (Mar 31, 2009)

dbsoccer said:


> Great stuff!! My confusion was that I have one camera with a proprietary Li cell that seems to last forever.


Lithium chemistries are used due to weight. For volume, the capacities are about even between NIMH and Lithium rechargeables, but Lithiums weigh much less. In many workloads, such as cameras, neither type performs better. You can get AAs anywhere, and the user has many primary and rechargeable options; LiPo saves you an ounce or two, and lets you design a more compact camera body.



> I have another camera that uses 4 AA cells. I tried a set of my 2700mAh Powerex cells (sorry for the 2900 typo) which seemed to drain very quickly. I use the Powerex in my bike headlamp very successfully.


Get a set of Eneloops and try them. You may be seeing issues with the high capacity cells aging...or you may have a hungry camera. If the Lithium primaries are getting more than about 50% better life than your NIMHs, then I'd say Turbo Guy is right, and it's those cells. Older 2200mAh and so didn't have those problems, but 2500+ got them bad, fairly often.



> Recharging the day before is not an issue but if I'm in a hurry perhaps having a set of Li primaries or a set of Sanyo's Eneloops at the ready would be the way to go. If I have more time, then I can use my LaCrosse BC-900 charger to refresh as set of 2700 NiMH.


The Eneloops can be used again and again, so economically they'd work very well. Just have a spare set ready. Also, LSD NIMHs seem to be immune to problems that crop up with high capacity cells, so are the general recommendation. I'm now using almost all LSD (Rayovac, due to retail availability when I needed them), because my other AA cells started performing like crap, eventually to the point of uselessness.



> A follow-on question: to retain cell life, we elected to turn the camera on and off over leaving it on. Is one type of cell better suited for reasons other than capacity for this type of use. Or is it recommended to leave the camera on and not cycle it. It was unclear why you'd select Eneloops over high capacity cells in one case and not the other.


When it comes to parasitic drain, or standby drain, no kind of cell will be better than another. Or, rather, all rechargeables are bad compared to primaries. I'm guessing it's more miscommunication, because I can't find where you asked about that in the thread. However, it shouldn't be an issue, unless you're leaving it on/standby for days at a time.


----------



## Sub_Umbra (Apr 1, 2009)

> Lithium chemistries are used due to weight. For volume, the capacities are about even between NIMH and Lithium rechargeables, but Lithiums weigh much less...


Are you sure? That's interesting. Can you source that?

Thanks


----------



## Benson (Apr 1, 2009)

Sub_Umbra said:


> Are you sure? That's interesting. Can you source that?
> 
> Thanks


Depends on the size. NiMH fans like to compare AA vs. 14500, which come out close to even, with Li-ion having an edge over LSD, and losing to high-capacity NiMH.

Comparing the 4/3AF to 18650, though, Li-ion wins hands-down, as 18650s are available above 2.5Ah capacity, and the highest 4/3AF I know of is 4.5Ah.

Then again, I'm not sure NiMH is as highly-developed in the 4/3AF size these days, since laptops have gone to Li-ion. Maybe the NiMH fans would point to subC or something?


----------



## csshih (Apr 1, 2009)

Sub_Umbra said:


> Are you sure? That's interesting. Can you source that?
> 
> Thanks



according to energizer's L91 Lithium AA datasheet, the lithium cells are roughly 3Ah.

the ni-mhs the op referred to are 2.7aH? pretty close (though the high self discharge might be quite a bit...)

on the other hand, rechargeable lico2 cells ahve a very very small self discharge rate... (but they can't be used in most consumer electronic, as detailed above.)

They are pretty light. I don't have a scale on me right now.


----------



## Sub_Umbra (Apr 1, 2009)

csshih said:


> according to energizer's L91 Lithium AA datasheet, the lithium cells are roughly 3Ah...


Thanks but that's apples and oranges. Crebie was referring to *Lithium rechargeables,* which have a much higher voltage than L91s, which are primary cells. 

What I'd like to see are the Ah ratings for two cells of the *same volume* with one being a NiMH and the other being a lithium rechargable.


----------



## Sub_Umbra (Apr 1, 2009)

Later that afternoon,

Well, this has been interesting. I've never thought of capacity in terms of volume before. I'm surprised at the results.

Common ratings for 14500 cells:

3.6v x 0.750Ah = 2.7Wh

3.6v x 0.900Ah = 3.24Wh

Common ratings for NiMH AA cells:

1.2v x 2.700Ah = 3.24Wh

1.2v x 2.900Ah = 3.48Wh

Eneloops:

1.2v x 2 Ah = 2.4Wh

Amazing.


----------



## cave dave (Apr 1, 2009)

Sub_Umbra said:


> What I'd like to see are the Ah ratings for two cells of the *same volume* with one being a NiMH and the other being a lithium rechargable.




Amp hour ratings would be pretty useless. 2700mah for Nimh and 750 mah for 14500's doesn't tell you much by itself.

What you would really want is Watt-hour ratings. In particular you would want WH ratings under load. But even that isn't as useful as runtime graphs of the two on the same device. 

Something like this. The energy density would be represented by the area under the curve, which is pretty similar. The edge goes to the LiIon but not by the hyped amount.


----------



## cave dave (Apr 1, 2009)

Sub_Umbra said:


> Common ratings for 14500 cells:
> 
> 3.6v x 0.750Ah = 2.7Wh
> 
> ...



The problems with these numbers is what they represent. The 2700 mAh of a Nimh is theoretically real useable capacity from the max voltage off a charger of 1.4v down to 0.9v on a low current draw. Real capacities are less.

The often quoted 750mAh of a LiIon is from 4.2v down to 0v. That would make it a one time use cell. If you stop using the LiIon at a more realistic 3.4v or so the capacity is much less. Real capacities are more like 500-600mAh for cells this size.


----------



## cerbie (Apr 1, 2009)

Sub_Umbra said:


> Are you sure? That's interesting. Can you source that?
> 
> Thanks


Not with, "Oh, here's a URL that says it," no.

Li-Ion battery shootout
NIMH battery shootout
Wikipedia list of battery sizes

I measured first by ruler/eye, so went with 14.5*50 and 17*34. Based on that, and pi as 3.14: 8252mm^3 for AA, and 7713mm^3 for CR123. Note that it's only those two. I know 18650 tends to be a good size ('naturally' good and then tons of R&D), but I couldn't find a comparison of enough cells at low current on short notice.

Note: 0.5A v. 2A is not ideal, no. But, it's more fair than 0.5A (4.1-2.5) v. 5A (1.4-0.9). Ideal, of course, would be constant wattage draw to test the batteries.

So, the CR123s I chose (good capacity, known reputable quality):
AW 750: [email protected]
Battery Station: [email protected]
Powerrizer: [email protected]

AAs (two high capacity, one I'd actually buy, if I knew when the shipments came in):
Sanyo 2700: [email protected]
Sanyo Eneloop: [email protected]
Accupower 2900: [email protected]

```
123 Wh/mm^3 @0.5A
AW 0.000268767017
BS 0.000287566446
Pz 0.000269285622
AA Wh/mm^3 @2A
Sa 0.000349854581
Ac 0.000332283083
En 0.000261512361
Average 123 then AA:
   0.000275206362
   0.000314550008 (+12.5%)
```
Note that the Eneloops approximately match the 123s.

Now, there's lack of "perfect" data (exact diameters and lengths per cell), bias in choosing the cell (I wanted to make sure Eneloops were in the mix, FI), differences due to choice of cell because of nice measurements (AA v. CR123; no 18650), rounding error (pi and diameters, mostly), etc.. *Generally, though, close enough.*


----------



## kuksul08 (Apr 1, 2009)

Great info here.

So... for a bike light that will be on for 2-3 continuous hours and usually recharged within a week of riding, the Sanyo 2700 is the best choice opposed to Eneloops?


----------



## cave dave (Apr 1, 2009)

Cerbie,

Awesome post! I love mythbusters!
:thumbsup:


----------



## Benson (Apr 2, 2009)

cave dave said:


> The problems with these numbers is what they represent. The 2700 mAh of a Nimh is theoretically real useable capacity from the max voltage off a charger of 1.4v down to 0.9v on a low current draw. Real capacities are less.


Yes, but multiplying that by 1.2V gives a decent Q&D, if _always_ high, estimate of the real capacity.



> The often quoted 750mAh of a LiIon is from 4.2v down to 0v. That would make it a one time use cell. If you stop using the LiIon at a more realistic 3.4v or so the capacity is much less. Real capacities are more like 500-600mAh for cells this size.


Not AFAIK; maybe some places are testing them this way, and that could explain the ~30% overrating of certain Chinese Li-ions, but that's not the standard, nor what reliable ratings seem to come from. AW, for example, seems to rate batteries fairly accurately (e.g.: SilverFox's Li-ion shootout, and rates his 14500s at 750mAh. There's an IEC standard for battery capacity, and it specifies the cutoff voltage for a 0.2C test at 1.0V for NiMH, and something between 2.5 and 3V for Li-ion (don't remember exactly), and manufacturers' data is usually similar.

The first 18650 datasheet I came across with google is here, and states capacity is to be tested to a voltage of 2.75V. Rated capacities with cutoffs in this region can be multiplied by the nominal voltage of 3.7V or, conservatively, 3.6V, to obtain useful results for comparison with similarly derived NiMH results; again, it will overestimate typical usable capacity in almost all applications, but it should correlate well.

Even that one result that I found a datasheet for -- 2200 mAh at 0.2C to a cutoff of 2.75V -- indicates a _minimum_ capacity of 2.2Ah * 2.75V = 6.05Wh, and in reality, the capacity is much closer to 2.2Ah * 3.7V = 8Wh. Only NiMHs with over 5 Ah ratings are even close enough competition to require examination of the actual discharge curves. And there are higher-capacity Li-ions out there -- check Lermite's tests on Ultrafire 3000mAh; they (predictably) don't make 3000 even at 0.2C, but they do pretty well (~2.8Ah) for low currents. There's also some Panasonic 2900s around, but I haven't seen the final tests on them.



cerbie said:


> Not with, "Oh, here's a URL that says it," no.
> 
> 123 battery shootout
> NIMH battery shootout
> Wikipedia list of battery sizes


Again, a comparison of Lithium primaries vs. NiMH rechargeables is apples-to-oranges, especially across dissimilar sizes. What's the point?


----------



## cerbie (Apr 2, 2009)

Benson said:


> Again, a comparison of Lithium primaries vs. NiMH rechargeables is apples-to-oranges, especially across dissimilar sizes. What's the point?


They're LIon, not primaries. I just used the wrong thread to link to at the top. Should have been this one. The CR123 cells chosen are the three at the bottom of that thread's first post. Even then, it's still apples to oranges, and will remain so. The point was to show that for arbitrary sizes, the chemistries were pretty close when it came to how much space they took up, since Sub_Umbra asked about that.


----------



## csshih (Apr 2, 2009)

Sub_Umbra said:


> Thanks but that's apples and oranges. Crebie was referring to *Lithium rechargeables,* which have a much higher voltage than L91s, which are primary cells.



whoops, sorry, read the post wrong.


----------



## oldrock (Apr 2, 2009)

I have no experience with the lithiums so won't comment on that but do have a bunch of experience with nimh AA cells. I've used most of the major brands and since I am a camera buff, I run thru a bunch of charges and can track how cells perform based on how many shots I get per fully charged set of 4 batteries. I also do alot of charges so can track number of shots per charge over time to see how cells perform when new and when used over time. 

I charge my nimh using only smart chargers that also can cycle the batteries to get maximum life out of a set of cells. Of the high mah rated batteries, sanyo 2700 cells win hands down! Nothing else I tried even comes close when used in high drain digital camera running at several frames per second burst mode. I have some sanyo cells with a few hundred charges over the span 2 years that still work pretty well. Not as many pics as fresh cells but still very servicable. None of the other cells do as well when fresh and most really die quickly ie. after maybe 100 charges they are only good for half the shots they did when new. Off the top of my head, I have tried energizer, duracell, ultracell, rayovac, and several generic ones and sanyos are the best I have found. I also have about 12 of the eneloop cells which I keep in my other cameras since they hold a charge for a long time. The eneloops are good but not nearly as many shots per charge as my sanyo 2700s. BTW, I also have some older sanyo 2500 cells that are still chugging along after 3 years. Not great performance anymore but still holding a charge which is alot more than alot of the other ebay high cap cells have done for me. 

bottom line, sanyo 2700 cells are what I use when I need max life and high discharge. Eneloop is what I use when I need long shelf life on a charge.


----------



## Sub_Umbra (Apr 4, 2009)

Thanks to everyone here. This thread has really changed the way I look at lithium secondaries -- and not for the better.

I understand that lithium secondaries have some advantages in weight, charge time and self discharge but for the most part what I've read here actually *further wrankles me* in regards to how difficult it is to find some products that still contain NiMH cells.

Paulr (I think) has complained about being unable to find a cell phone that runs on NiMH and I would like one, too, especially since the performance advantage seems pretty much non-existant. The same is true of other devices, like mp3 players. While a few NiMH powered mp3 players are out there, if one could only choose between *them* -- one would restrict the 'feature set' by quite a bit. For both phones and mp3 players I really don't care as much about weight as I do about other factors.

This thread has driven me *further yet* from lithiums for many applications.


----------



## moldyoldy (Apr 4, 2009)

Sub_Umbra said:


> Thanks to everyone here. This thread has really changed the way I look at lithium secondaries -- and not for the better.
> 
> I understand that lithium secondaries have some advantages in weight, charge time and self discharge but for the most part what I've read here actually *further wrankles me* in regards to how difficult it is to find some products that still contain NiMH cells.
> 
> ...



Sub-Umbra, I certainly concur with your change of mind! For well over a year I wandered thru a variety of Lithium-something cells in sizes from RCR123a thru 10440, 14500, and 18650 cells and the associated expense of matching chargers with cells. Even as a techie-geek, I have to acknowledge that unless you have some overriding business reason such as LEO or Fire or EMT or SAR or MIL, the fuss, bother and worry is not worth it. I would have spent far less $$ or Euro by purchasing primary cells if I really felt I needed a Lithium-based flashlight. I stopped purchasing any Lithium-xxxx lights and will gradually give away or sell whatever I have amoung my lithium-xxx cell based chargers or the 4 remaining RCR123a lights. 

Worse still, the incompatibility between so many Li-Ion cells and chargers, or the variability of the consumer-grade chargers themselves, coupled with the inherent dangers in the rechargeable Lithium energy technology as evinced by ample published cases of rapid dissasembly with considerable heat and fumes emitted, causes me to simply say - enough. If I run a 2xAA flashlight down to the point that a cell reverses, I do not need to worry about something unpleasant happening. I accept the shortened cell life if I need the light. Having a Li-Ion cell protection cut out and leave me in the dark is more than irritating!

From a design standpoint, the strong consumer preference for a super small size drove the designers of digital cameras and MP3 players to lithium-something batteries. If the design requirement is long operating time with the smallest space claim, cylindrical cells cannot match the energy density of foldable or flat Li-xxx batteries. The exceptions are becoming rare. My older daughter found a small off-brand digital camera that used 3 AAA cells. of course, the enclosed alkaline cells were unusable in about 10 minutes of use. Only Ni-MH AAA cells provide any decent run-time. That digital camera size is readily available if you are willing to accept a battery design incompatible with just about anything else.

Furthermore, as LED technology develops, the differences in lumens output between battery types are shrinking. The EagleTac P10A2 with 2 NiMh cells outputs about the same amount of light as the EagleTac P10C with a single RCR123a cell. Many tradespeople have told me that there is an optimum size for a flashlight. ie: the smaller single-cell CR123 lights are really too small for regular work. The NiteCore D10R2 has about the same light output as the NiteCore E10R2. The size difference between the D10 and E10 is close. 

Yes, I have been a flashaholic since childhood with the use of kerosene lanterns and flashlights with nearly every storm coming thru. For flashlights, I gladly made the switch from Ni-Cd to Ni-MH, but not to Lithium-something. Maybe I am getting old......  However my several laptops run quite nicely on Li-Ion cells, and, Lord willing, I will live long enough to purchase a hybrid car. Hey, maybe there is hope for me yet!


----------



## cave dave (Apr 5, 2009)

moldyoldy said:


> ... I would have spent far less $$ or Euro by purchasing primary cells if I really felt I needed a Lithium-based flashlight...



I'm with you on this one! Somehow "free lumens" didn't end up being so free after all. :shakehead

I have 6 RCR123's and two chargers (WF139 and Pila). This is a small collection compared to some, yet still represents $100+ in rechargeable investment. I could have just bought a case of SF primaries and had a lifetime supply, and my lights perform better on Li Primaries and have a nice moon mode at the end. 

Two of the six RCR's are below 80% now. I have heard that LiIon batteries are only good for about 3 yrs even unused, and even if they lasted longer CPF's like us would want to upgrade to the latest higher performing ones. Seems like ya need a new charger every 3 yrs or so too. 

The only reason now I have RCR123 lights at all is the Ra lights are so fantastic. If there was an AA Ra equivalent, I could get rid of all my RCR123 powered lights. Note: I tried the LF5XT and it fell far short of the Ra IMHO.

PS The really really big advantage of free lumens for a flasholholic is I get to use my lights alot more than I would if only used them when I really needed them. Which is what I found myself doing when paying for Li primaries. No fun in that. Its like having a sports car but never driving it because it guzzles gas.


----------



## LouRoy (Apr 5, 2009)

As someone who uses flashlights daily in my work, I would spend approximately $1200.00 per year on primary batteries. Thus, I use rechargeables almost exclusively and they save me a lot of money. I accept the risks and limits of rechargeable lithium batteries as a trade off for the reduced cost. I have successfully used them for four years without any problems so far (knock on wood). 

I agree that if you use a flashlight only occasionally, it may not make sense to use rechargeable lithiums. But I think you owe it to the planet to use rechargeable NiMH AA and AAA batteries as much as possible.


----------



## moldyoldy (Apr 5, 2009)

LouRoy said:


> As someone who uses flashlights daily in my work, I would spend approximately $1200.00 per year on primary batteries. Thus, I use rechargeables almost exclusively and they save me a lot of money. I accept the risks and limits of rechargeable lithium batteries as a trade off for the reduced cost. I have successfully used them for four years without any problems so far (knock on wood).
> 
> I agree that if you use a flashlight only occasionally, it may not make sense to use rechargeable lithiums. But I think you owe it to the planet to use rechargeable NiMH AA and AAA batteries as much as possible.



Conversion to rechargeable cells - Absolutely! Although I started out as a kid with non-rechargeables, as soon as GE marketed their Ni-CD cells I converted and never looked back. Back then a good AA Ni-CD was maximum 450mah...

FWIW, I just converted one of my fellow choir members at church to an up-to-date LED flashlight and rechargeable cells - the P10A2 and LSD AA cells (Imedion). He is very happy with the brightness and runtime even though he uses the P10A2 primarily on high output during work. He was really turned off (pun) by the fast self-discharge of the usual Ni-MH cells and the usual (dim) LED flashlights available in consumer stores. He has an interesting style of flashlight usage in his plumbing work: He slides the P10A2 up under his sleeve on the top of his wrist to illuminate his work - sort of a poor-mans head-light (Stirnlampe). He also likes that the P10A2 beam on high will illuminate the interior of a pipe all the way to the other end some 10-12ft away. The other maintenance people at my church have either Fenix or EagleTac something - everyone is happy with the available brightness and rechargeable cells are assumed!


----------

