What's the smallest lithium ion cell I can find?

[BatteryCharger]

What\'s the smallest lithium ion cell I can find?

I want to modify a "ziplight" flashlight. It's a flashlight that was made to fit into the case of a Zippo in place of the lighter. It has been discontinued and uses a proprietary battery pack that you can't buy anymore. Can anybody tell me what the smallest size lithium ion cell is that I could find? And what type of pack might I find that in?

Thanks /ubbthreads/images/graemlins/smile.gif

 

[billw]

Re: What\'s the smallest lithium ion cell I can fin

how about:

80 mah (but considered 90 mah), 9/16" x 3/4 x 5/32", 2.2 grams: $8.50.

There are thinner cells about 1 inch square.

See http://www.rcmicroflight.com/cloud9rc/

BillW

 

[paulr]

Re: What\'s the smallest lithium ion cell I can fin

Why lithium ion? Do you mean ordinary (non-rechargeable) lithium? There are all kinds of lithium coin cells available including some very tiny ones. Lithium ion needs special charging circuitry.

 

[BatteryCharger]

Re: What\'s the smallest lithium ion cell I can fin

No, I mean rechargeable. I'm hoping to find a pack of some sort that I can take apart so it will have the protection circuit.

 

[BatteryCharger]

Re: What\'s the smallest lithium ion cell I can fin

I was just taking a look at the battery for my cell phone, it's about 1.5" square, 3.7v. Would I be correct to assume that it's probably only one cell in there?

 

[paulr]

Re: What\'s the smallest lithium ion cell I can fin

Yes, there's likely to be just one cell (prismatic shape) in there. There are smaller cells available from places like digikey.com. You could also dismantle a Swisslight, if you want to spend a bundle. If you're just trying to build a Photon-like LED light into a cig lighter, I'd say just use normal 2016/2032 coin cells.

 

[PeLu]

Re: What\'s the smallest lithium ion cell I can fin

replacement batteries/cells for cellphones are easily available and pretty inexpensive, the same for chargers.

But I don't know if they are small enough for you (but many of them would fit easily into a Zippo)

The Swisslight does not contain a Li-Ion cell, AFAIK, but at
Li-Ion coin cells some are available

 

[BatteryCharger]

Re: What\'s the smallest lithium ion cell I can fin

Those lithium ion coins would be perfect! Does anybody know what I could use as a protection circuit on that? Making something from scratch is out of the question for me, but maybe taking one from a larger pack?

 

[JamesWong]

Re: What\'s the smallest lithium ion cell I can fin

The Li-ion rechargable battery used in my digital camera : Pentax Optio S is smaller than mobile phone's. It measures 35mm x 40mm x 6mm rated 3.7V 710mAh. The model number is D-L18. Same battery is also used in one of Fujifilm small DC, but they use another part number. They are interchangable. They have all the required protection circuit. Charge should be available from Pentax or Fujifilm as an accessory. No compatible charger is seen here yet.

A compatible D-L18 is sold here at around US$20, while the original is US$3X.

From Google, search for D-L18. You will find a lot :

http://www.walmart.com/catalog/product.gsp?product_id=2422845&cat=5429&type=19&dept=5429&path=0%3A3944%3A3959%3A4468&xsell=2178368

Hope this can help. /ubbthreads/images/graemlins/smile.gif

 

[tvodrd]

Re: What\'s the smallest lithium ion cell I can fin

The one in my Canon digital elf (NB-1LH) is 1.96" X 1.27" X .400" and is rated 3.7V, 840mAH. Charger for it is abt the size of a pack of cigarettes and has fold-out prongs for the outlet. They sell an automobile lighter plug-in version also. I've considered building a light based on one.

Larry

 

[PeLu]

Re: What\'s the smallest lithium ion cell I can fin

[ QUOTE ]
JamesWong said:
The Li-ion rechargable battery used in my digital camera : Pentax Optio S is smaller than mobile phone's.

[/ QUOTE ]
Yes, that is the size which is used in mobile phones, too.

I would just use one the available chargers for it and not care too much about deep discharge:
1. it is not dangerous (for the user) to deep discharge the cell, it just makes the lifespan shorter or kills it. And the cell is pretty inexpensive, here you can get it for little more than a Duracell CR123A .-)
2. When you use a white/blue LED, it will be pretty dim at 3V anyway, so it is easy for you to tell that you need a recharge. Only in the case you had it accidently switched on.

 

[Willmore]

Re: What\'s the smallest lithium ion cell I can fin

B.G. Micro has some lithium rechargable coin cells. They're Lithium Vandium Pentoxide, so they're not Li-ion per se. /ubbthreads/images/graemlins/smile.gif They are nice. I've got a half dozen. IIRC, they were just over a $1. You might also look at some of the cells used in Motorola StarTac cell phone packs. They'd fit in a zippo, but I don't know if they'd fit in there with much else. Oh, also check the cells in the newer Nokia phones, they're pretty darn small. I think I have one that is 600mAh and some larger ones that are 1Ah.

 

[3rd_shift]

Re: What\'s the smallest lithium ion cell I can fin

Another possibility may lie in the neighborhood of cordless phones. /ubbthreads/images/graemlins/huh.gif
These are usually easier to connect than cellphone batteries are. /ubbthreads/images/graemlins/tongue.gif
A trip to the battery section for cordless phones with your zippolight in hand may reveal a battpack that will fit. /ubbthreads/images/graemlins/wink.gif
All you will then need to do is, find a cordless phone at a 2nd hand store, or wherever you like that takes that battpack model number to charge it, and presto! /ubbthreads/images/graemlins/thumbsup.gif

 

[Doug Owen]

Re: What\'s the smallest lithium ion cell I can fin

As others have suggested, I think the answer is in the small digital cameras. While mine is pretty big, but there are some pretty bitty ones out there.

OTOH, why not look into NiMH cells? Like for instance the ones in the 9 volt battery?

Doug Owen

 

[3rd_shift]

Re: What\'s the smallest lithium ion cell I can fin

9 volt battery looks like a good idea.
Many of the rechargeable ones come with 6 aaaa sleeved cells in them.
Take it apart, and there ya go.
You will need a cheap, slow as arctic molasses, smart charger for them though.

My other suggestion would be to just bulk order some throwaway lithium cells, and convert that zippolight to a single led if practical.
Many of these 3 volt lithium coin cells have just enough oomph to direct drive a t3, or t5 led from www.lsdiodes.com, or wherever you can find a good inexpensive white led.
If you want to go with a triple 3.6 volt nicad setup, you could also drive that led to a good brightness level.
The nimhs may be a bit too hot for direct driving an led.

I have many times, taken the 3.6 volt battpack out of an old cordless phone and stuck a bare blue, or white led in the connector and taken that to dance clubs on the weekends with battery in hand and led sticking out from between my fingers. /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/buttrock.gif
When I came back home, I put the battpack back in the phone.

 

[3rd_shift]

Re: What\'s the smallest lithium ion cell I can fin

Want an even easier way?
Nab a keychain led light with the led and batts, and mod those into the zippolight. /ubbthreads/images/graemlins/thumbsup.gif
www.countycomm.com has 20 of those for about $20 bucks. /ubbthreads/images/graemlins/smile.gif