New to 'non-standard' rechargeable world & need advice

I'm about to buy my first light that takes anything other than standard sized cells (AA, C, D, CR123) and I'm looking for some reassurance.

The light is a Romisen RC T5 and although it can take 123s, I want to run it on 18650s. So to go with it I'm going to order AW 18650s (I understand AW is regarded as the best quality) and an Ultrafire WF 139 2-bay charger. There is a cheaper charger at the supplier but I'm looking for quality, but also I want to future-proof and this one can charge "14500, 17500, 17670, 18500, 18650 batteries. Will also charge RCR123 cells with suitable spacers." Trouble is, I have no idea what these numbered cell types equate to. My tag line lists my current lights, could someone tell me which of my lights can use which cells? Which ones need extension tubes and which could be used as they are? How do I work out what size of "suitable spacers" are suitable?

I think you will find that member mdocod has the encyclopaedic knowledge here regarding compatibility between cells and lights. Do a bit of searching and you will turn up lots of info.

However, the key facts are that the cell numbers relate to their dimensions in millimetres. An 18650 for instance is 18 mm diameter and 65 mm long. The 0 indicates a cylindrical cell.

The numerical designation is usually reserved for lithium ion cells, and such cells usually have a nominal voltage of 3.7 V. (A bit higher when charged and a bit lower when discharged.) There are special cases but that is typical.

So for compatibility with lights you have to match physical size and also voltage. In many cases the voltage is incompatible with what the light expects and you have to change out the bulb or the LED driver board. Some LED lights have more flexibility about input voltage and those are easier to use lithium ion cells with.

Before I dig into your list of lights, I'm going to point out that in order to go rechargeable on all of them, you will pretty much have to have 3 different rechargeable chemistries and 3 different chargers to get the best results in all areas. I'll list the 3 chemistries you will want to look into having to run everything, then go into what goes where to the best of my ability.

1. 1.2V NIMH rechargable cells: In various common sizes (AA, C, D etc), these you are probably already familiar with so I won't say too much more on this subject. Investment in a good multibay smart charger like a MAHA 808 is highly recommended if you are going to accumulate a number of NIMH cells for various devices. I also highly recomend owning nothing but Low-Self-Discharge cells, like eneloops in AA, and LSD Accupower cells in C and D sizes.

2. 3.7V Lithium Cobalt Oxide (LiCoO2): This is what we are talking about most of the time when we say lithium ion. This is what AWs li-ion cells are, and is what the WF-139 will charge. Make sure you get a WF-139 with the spacers for charging RCR123s, all other sizes you have listed will fit without the need for spacers. As a side note, a RCR123, is equivalent to a 16340 size cell. If you can afford it, I would suggest a Pila IBC charger. It is a more robust charger with better quality charging characteristics. The WF-139 will overcharge cells if you leave them on the charger. AWs protected cells are the best value IMO.

3. 3.0V Lithium Iron Phosphate: The chemistry of these cells is almost always indicated in the description or name as "LiFeP04" . These are a semi-new breed of cell. They have substancially lower overall power density than the li-ion described in "2" above, but they have some distinct advantages: they are closer to the operating voltage of CR123 primary cells, so can often act as direct replacements for CR123 primaries in devices that don't tolerate the higher voltage of LiCoO2 cells. they are "safe" chemistry cells, they can be abused, overcharged, over-discharged, overheated, punctured, smashed, etc, without much risk of flame or explosion. There are some LiCoO2 cells out there with voltage reducing diodes built in to have an output closer to 3.0V like the LiFeP04 and CR123 primary cells, but the problem there, is the protection/voltage regulation all adds components that can fail. The simplicity of the LiFeP04 cell, even though it has less capacity, is often worth the tradeoff for it's reliability. I suggest a kit like this for simplicity sake: http://www.batteryjunction.com/2rc375reliba.html add extra cells to the order if needed.
.....However, for flashlights, or configurations that can tolerate the higher voltage of LiCoO2 cells, I still recommend high quality protected 3.7V cells...

Gladius: 2 3.0V LiFeP04 RCR123 cells is a good solution. I have read of people using pairs of 3.7V cells in these, but I don't think it is good for the light, someone correct me if I am wrong here.

SF E1e+KL1: I think you can run a 3.7V RCR123 here, however, it will overdrive it to the tune of, well, a lot brighter than stock, as I understand it, when the input voltage rises above the Vf of the the configuration, it just goes into direct drive. Get confirmation on this before attempting as I am not 100% sure on this. I am pretty much 100% sure you can use a 3.0V LiFeP04 RCR123 in this configuration to maintain close to stock operation, but with shorter runtime.

SF E2e+KL4: I think the most common method here is to use a single 3.7V 17670 size LiCoO2 cell, someone correct me if I am wrong.
(on a side note, I believe you could put the KL4 on the E1E and run a 3.7V RCR123 in the E1E for a more compact, albeit shorter running little pocket rocket)

SF G3: A Pair of 17500 size 3.7V cells for the P90, or any lamp up to and including the LumensFactory EO-9. Do not run the P91 on 17500s as it is above the maximum safe discharge rate.

G2L: A pair of 3.7V RCR123 will work fine if you want flat regulated output at it's maximum possible output with reduced runtime. A single 3.7V 17670 will also work well, but will have tapering off output but very extended runtime compared with the 2 RCR123s.

9P+LED+FM34+Z49: assuming by "LED" here you mean the surefire LED drop-in, in which case, a pair of 3.7V 17500s is a perfect replacement.

Fenix L2T: 2 AA size 1.2V NIMH

P1DCE: 3.0V LiFeP04 RCR123 cell.

P2DCE: 3.0V LiFeP04 RCR123 cell.

P3DCE: 2 3.7V RCR123s.

L2DCE: 2 1.2V NIMH AAs.

P2D R100: 3.0V LiFeP04 RCR123 cell.

P3D R100: 2 3.7V RCR123s.

T1 SMO: Pretty sure it's compatible with 2 3.7V RCR123s.

Mini-Mag AA+TerraLux 5WLED: Assuming NIMH AAs here?

Mag 2D+TerraLux 5WLED: probably NIMH Ds

6D 'Skull Basher: NIMH Ds I'm thinkin..

LumaPower M3 Transformer + turbo head: You can run it on 1x NIMH AA, 2x NIMH AA, 1 3.7V 14500 or 1x 3.7V RCR123.

Gerber Sonic: NIMH AAA

I vote to make this a sticky! :twothumbs

3. 3.0V Lithium Iron Phosphate: The chemistry of these cells is almost always indicated in the description or name as "LiFeP04" . These are a semi-new breed of cell. They have substancially lower overall power density than the li-ion described in "2" above

Click to expand...

LiFePO4 has lower energy density, not power density. LiFePO4 actually has much higher power density, for example many are able to dishcarge 15C, or 15 times the nominal current safely, where the Cobalt type is gnerally limited to 2C, or double the max rated capacity (eg, a 2.2Ah lithium cobalt cell would be limited to no more than 4.4 amps).

Another LiIon chemistsry out there is LiMnO2. A common brand name here is "Emoli". These are conveniently also 3.7V, yet higher power density and inherently safe, like LiFeP04. Their energy density is less than LiCoO2, but more than LiFeP04.

2xTrinity
I've misspoken. knew it felt wrong coming "off the fingers" last night. Thanks.

Actually, within the confines of the batteries being discussed, an 18650 LiCoO2 has better power density than any RCR123 sized LiFeP04 I have seen. So, blah!

----------------------------------------------------

Tomcat,
please ignore the concept of the Emoli (LiMnO2) cells for the moment as they are only available in 2 sizes last I checked, and only 1 of those sizes would fit in only 1 of your flashlights. Not worth a 4th chemistry to be concerned about at this particular juncture.

mdocod said:

Before I dig into your list of lights, I'm going to point out that in order to go rechargeable on all of them, you will pretty much have to have 3 different rechargeable chemistries and 3 different chargers to get the best results in all areas. I'll list the 3 chemistries you will want to look into having to run everything, then go into what goes where to the best of my ability.....

Click to expand...

Wow mdocod that's a fantastically detailed post.:bow:
You've given me a lot to think about.

[Hello Mr. Happy and thanks. :wave:]

Regarding all my AA lights, I already run them on a mix of part used alkalines or Energizer lithiums salvaged from work. I do a lot of photography and put fresh cells in my flash guns every other job regardless of remaining charge, although the AA lithiums do seem to last forever. Since the advent of Cree LEDs these half used cells take a long time to get sucked dry. My favourite around-the-house-with-old-batteries light is the L2D R100. I'm also trying the new low self-discharge AAs. After years of buying ever higher capacity NiMH cells and being disappointed that they were dead when I actually wanted to use them, I tracked down some Eneloops after reading about them on Flashlight Reviews shortly before it closed. They're hard to come by in the UK (or they were when I bought them last year) so I went to an industrial electronics supplier. I'm suitably impressed and don't see the point of going back to regular NiMHs now. I am also trying the highstreet available Uniross Hybrio variety, and GP Recyko+ bought from Glowgadgets.com. I haven't done any direct comparisons but they all hold their charge well for weeks at a time and are ready when I need them. Last week I bought a new charger to go with the AAs, a MAHA Powerex MH-C9000 WizardOne. I'd never heard of MAHA before and as I bought it from a UK electronics chain (Maplin) who are kind of synonymous with the cheaper, strange brand end of the market, I wasn't sure what to expect but was very pleased with the charging control and programme features. I love the way the C9000 treats each cell individually according to its needs and ability to refresh unstable cells. I would recommend this unit for any AA and AAA user. I was even happier to find that CPFers rate it too.

As for D cells, I've pretty much given up on those. I used to have all the even numbered Maglites but frankly only the 2D was of any real use. 4D is as big as you'd ever want to carry and the 6D is just for showing off. (Doesn't even make a good club!) I gave away the stock 4D to my brother who thought it was the greatest thing ever, until I blew it away with my P1DCE Q5! I have no practical use for the 6D so I will sell it. Yes I know I could ROP it but that means shipping parts from the States and I'll end up with a massively bright torch that's still too big to carry. I'll keep the 2D as a loan unit. Last week I tried it out with 2 AA Eneloops and D cell converters and it works just fine so I'll leave it that way.

I think I'll leave the single CR123 lights as they are since they are mainly used for short bursts of light and are intended as EDC back ups so sit doing nothing for long periods until called into action.

The multi-cell lights are the ones that I really think need to be on rechargeable, especially if I go above 3 cells. I'm going to go with your suggestion for the G3 and 9P. The G3 I've left as incan (because it won't work with any of my non-Surfire LED drop ins, only an SF P60L) but of course it does eat cells. The LED in the 9P is a 750ma 3.7-9v Cree from Lighthound. I also have a cheap Chinese 9v Cree from eBay. Both work without issue in the 9P but not with the G3. I actually wanted the G3 to be LED but I'll live with it this way around. I'll also go for the E2e+KL4 option. I love the wide flood on that light but at a straight 100 lumens it is a bit battery heavy.

So it looks like I'll be getting AW 17500s and 17670s now. I will wait on the RCR123s for the time being. If I do decide to buy the Romisen I will get 18650s for that. Is the 18650 size a common type for this 'class' of high output light? My thinking is that I would obviously want to use 18650s on other lights too in the future, especially as P7 LEDs start to become more widespread. Future-proofing you know. Possibly I'm over-thinking this?

I'm so glad you told me about the Ultrafire WF-139 overcharge issue. I would have bought that one because it seemed better quality than the generic ones on offer. Just goes to show how specs can be deceptive if you don't know what you're doing. I have looked around a couple of other threads and Ultrafire chargers don't seem to be that well regarded. I assume the Pila IBC will do all the cells I need? Where can I get one? Do you have a rough idea of price and a trustworthy supplier?

Many thanks for going through this much effort. I appreciate it and I've learned a lot.

Hi Tomcat, sorry I didn't get back to you sooner.

The IBC charger can be found here for a good price:
http://www.flashlightz.com/product.php/pila/bc01-ac01/?product=171829&category=1225

You may need to get some dummy spacers or dummy cells to charge shorter cells like RCR123s and 17500s, I *think* you would need to find a pair of ~15mm spacers and a pair of ~32mm spacers (A ~32mm spacer would be a CR123 dummy), you could probably make something out of a bolt and a wooden dowel. Check lighthound for these, they might have something.

18650 cells are the best bang for the size. That extra mm buys about 30% more capacity over the 17670 size. So in the future, you may want to seek out lights that support this cell size. Or, convert lights to support them. Check out the leefbody parts available at lighthound.com to check out some of the SureFire body options. A 2x18650 body can be used to drive your 9V (3xCR123) configurations, it's the same length as a 4 cell body, but has the advantage of a ton of available power. A set of 3 CR123s has about 11 watt-hours of energy available (depending on load), a 2x18650 configuration gives you about 16 watt/hours. So it can either extend your runtime, or make running higher powered lamps more practical. Another comparison worth noting, a single 18650 has about the same amount of energy as a pair of 17500 cells.

There are a large number of brands available that "specialize" in building lights for the 18650 cell size, so many have been popping up lately it would be hard to list them all. Wolf-Eyes and Pila were really at the forefront of the movement to 18650/18500 powered lights, and they are still going strong.

The Pila IBC charger is available from FlashlightZ (www.flashlightz.com), an advertiser here on CPF. I believe that they are still on sale for $36.65. Look under 'batteries' on the 2nd page. Shipping is about $7.95 or free if you spend $100.

I recently did a group buy and they're an excellent company to deal with. They also carry the Pila cells that are pricey, but I believe are excellent cells. I guess it's a you-get-what-you-pay-for situation.

That said, I agree that AW has the best value in cells and his are what I use. In addition to good quality cells at value pricing, his service is second to none.

Good luck with your new chemistries. You're wise to do extensive homework before jumping on board.

To mdocod --


Thank you for your very detailed answers. :thumbsup:



Yes, this thread should oughta' be made a "sticky".

:wave:

_

Thanks guys. I had done some searching myself and the charger seemed to be a bit of an elusive creature. Swiss designed, Chinese made, but only available in America. I did find a French site which sells them but you can't actually click on it so I assume they are out of stock. I checked out Flashlightz as you suggested and all looked good, especially the price. I even ordered some Pila cells (gotta love a government expense account!) but unfortunately I could not process the order. The site itself only takes US zip codes, not international post codes, and using their Google ordering interface the process stopped because it said that they will not ship to that address. There is no specific mention on their site that they do or don't ship internationally. A clear yes or no would be helpful. I'm not deterred though. I shall email them for a straight answer. If this charger is so tricky to get yet so sought after, turning down international sales doesn't seem logical. I'll let you know the results.

I agree with Flashlight Aficionado and Burgess that this thread should be a sticky. There's so much good info for newbies to lithium rechargeables that it's worth having it easily to hand. To anyone in my position looking for detailed advice on rechargeables, mdocod has posted a lot of valuable information around CPF on the subject so have a search. You'll learn a lot.

By the way, the Pila website has an interesting downloadable PDF chart detailing cell compatibility with a wide range of major flashlights. It's a bit out of date but makes interesting reading.

Update 01

Regarding the international availability of Pila products from Flashlightz.com, the official word from them in answer to an email query of mine is 'Yes we can only ship to the lower 48 states in the U.S. '
So no luck for anyone outside the US like me.

I'm currently in contact with Pila in Hong Kong to see if I can buy direct from them. Will post the results. Well I will if I can ever get my home broadband up and running again!


Update 02

Pila replied and sent me a product sheet pdf and a price list. They do not have a direct link for purchasing online because apparently they do not want to be seen as a retailer, which I suppose makes sense as they wouldn't really want to get bogged down with lots of small orders. You have to email them with your order and they will send a pro forma invoice which you then pay by PayPal. They're email communication is good and quick. Yea for Jennifer Wong!

The prices are very high. $50 for the IBC charger, compared to $36.65 at Flashlightz.com. The batteries are between $20-27 each! On top of that the shipping to the UK is $35 (but that was for my order of the charger and six different cells) Their prices are listed in US dollars. Their quoted delivery time is 1-2 days after full payment, which is very good if true. Before you ask why I would pay such a steep price, I didn't. My employer is forking out for this.


So for non-US residents the only reasonable way of getting Pila products is to make a friend in America and have them delivered there then forwarded or check out the CPF Market Place. Otherwise you have to just limit yourself to the charger. Funny when Pila stuff isn't US made in the first place! :thinking:
They really need some distributors outside America so the rest of us can get our hands on their highly recommended charger.
I'll let you know how long my charger really takes to arrive.


Update 03

:twothumbs I got my charger yesterday. Taking into account the UK/Hong Kong time difference it took three days from my perspective from the time I received an email telling me the order had been sent to the time it actually landed in my eager hands. Judging by the timing of the email, I reckon it took them about four hours from receiving my payment to dispatching my order. Kudos to Pila.

The charger came in a nice thick black card box with Pila printed in silver on it. The charger looks well made and is very small and dinky, and comes with a black draw-string travel bag and international mains pin adapters so you can take it around the world. The input AC voltage range is 100-240v at 50/60Hz automatic detection so you can keep your lights going in any country. For in-car charging, there is an optional 12v adapter. The instructions are clear and pretty idiot-proof. Also supplied are two screw in spacers for charging smaller cells. The batteries feel hefty, solid and expensive. At those prices they should be! I've never had a Li-ion charger before so I've nothing to compare this with, but I feel confident with it thanks to the recommendations received and I'm glad to have opted for quality from the outset.

So far I've only had time to charge two sets of Pila 300S (17500) cells and used them in a 9P w/Lighthound Cree and a G3 w/P90 but they both work fine. To my eyes, the G3 seemed to be noticeably brighter than on primaries. As a point of interest, I found that the 600S cells, which are supposed to be the equivalent size to 17670 do not fit an SF E2e body. They are a little too thick to allow the cell to drop all the way to the bottom of the battery tube so the head cannot be put back on. The fit on a G2L is a bit snug and you may have to remove the head to push the cell through to remove, but otherwise the 600S works perfectly. I assume that when I eventually start buying AW cells, these size issues will be less of a problem.

Overall I'm very pleased with the Pila set up and it's quality and I am glad I've got it. The transaction was easy and delivery very fast. The prices highlight the need for more distributors outside the US or for some other manufacturer with a wider distribution network to make a charger of equal quality. Now my only problem is that I'm getting really tempted to buy a Pila torch as well!


Update 04

Regarding the issue of Pila 600S (17670) cells not fitting the E2e body. I did a bit of searching through various threads and found that I'm not the only one with the problem. Others with different brand 17670s have come across this issue and it's not limited to just the E2e. L2 and L4 torches have the same problem but, interestingly, not all versions of the same model. You can find two people, both with say L2s, and the cells will work for one but not the other. The issue is with the inside of the battery tube being tapered just enough to stop a Li-ion cell going all the way to the bottom, but allowing CR123s. Initially I was disappointed but after reading other people's experiences I decided to take a gamble and Dremmel out the last 10mm of the tube. It was a bit tricky as I have no single drill bit to do the job so I used a succession of abrasive bits and proceeded slowly. The aim was to shave off a small amount of metal all the way around the bottom of the tube without damaging the metal collar which stops the battery falling all the way through. I decided to orientate the body with the clip at the top and called that the 12 o'clock position. As I'm right handed I worked only on the right arc of the tube, counting the number of passes of the abrasive bit on that side. Then I rotated the tube to the 6 o'clock position and repeated. I was concerned about leaving the tube lopsided and jamming the cell which is why I counted the strokes of the bit. Every so often I stopped and blew out the debris with compressed air and wiped the tube clean before test fitting the battery. When I finally got to the stage where the cell would just about fit and the light worked, I gave the shaved area a good going over with a tiny brass wire cup brush to smooth out the metal. Lastly I smeared a thin film of silicone grease on the metal with a cotton bud (to aid battery movement) and rubbed it in so as not to leave an obvious greasy mess. The current state is that my E2e with a Pila 600S will now power the KL4 head perfectly. The cell is rather tight into the body and requires a lot of shaking to get the cell out or removal of the tailcap and a bit of pencil eraser pressure to get it out, but it does work. I reckon I must have shaved about 0.3-0.5mm of metal from the last 10mm length inside the tube. When I get time I'll have to go back in and shave off a little more to improve the fit. Right now although a little of the print on the cell skin got slightly worn, there are no gouge marks or actual damage so I'm very happy I can now EDC this juice hungry torch.
:thumbsup:

mdocod said:

You may need to get some dummy spacers or dummy cells to charge shorter cells like RCR123s and 17500s, I *think* you would need to find a pair of ~15mm spacers and a pair of ~32mm spacers (A ~32mm spacer would be a CR123 dummy), you could probably make something out of a bolt and a wooden dowel. Check lighthound for these, they might have something.

Click to expand...

Is a DIY option like that safe? Now I have the IBC and it does come with screw in spacers for the 17500. I've checked Lighthound and spotted CR123 spacers so that and some AW RCR123s might be my next purchase.
I assume that the reason for the spacers is that you cannot put two RCR123s in a single bay so they must be charged separately?

mdocod said:

18650 cells are the best bang for the size. That extra mm buys about 30% more capacity over the 17670 size. So in the future, you may want to seek out lights that support this cell size. Or, convert lights to support them. Check out the leefbody parts available at lighthound.com to check out some of the SureFire body options. A 2x18650 body can be used to drive your 9V (3xCR123) configurations, it's the same length as a 4 cell body, but has the advantage of a ton of available power. A set of 3 CR123s has about 11 watt-hours of energy available (depending on load), a 2x18650 configuration gives you about 16 watt/hours. So it can either extend your runtime, or make running higher powered lamps more practical. Another comparison worth noting, a single 18650 has about the same amount of energy as a pair of 17500 cells.

Click to expand...

Yes 18650 does seem to be the way to go for the bigger lights. I looked up the Leef 2x18650 body and I'm sorely tempted. Although it's costly, it does add a whole new range of options for configuring my 9P and G3. I knew the moment my credit card shrieked and ran under the couch that this is the right thing to do.