3.6V Lithium AA Battery: Candidate for LS Use?

3.6V lithium battery the size of (1) AA. SAFT part # LS 14500. Maybe a possible candidate for LS mods or super-small "1-cell" LS ? I discovered these in use for some industrial PLC memory backup applications. Think I saw an equivalent battery in Parts Express catalog. Anyone else know anything about these?
John

The memory backup 3.6V lithium cells tend to have very low current delivery capabilities, a few mA. Would be OK if you want very low light levels for 100s of hours. No resistor required.

Like Doug sez, these have VERY low current delivery. I had heard a tip of using two of the 3.6v lithiums in a mini-mag to power a single nichia. THis was one of my first mods and it works well.

Originally posted by Illuminated:
3.6V lithium battery the size of (1) AA. SAFT part # LS 14500. Maybe a possible candidate for LS mods or super-small "1-cell" LS ? I discovered these in use for some industrial PLC memory backup applications. Think I saw an equivalent battery in Parts Express catalog. Anyone else know anything about these?
John

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<font size="2" face="Verdana, Arial">I used two of these batteries, Li-ion rechargables, in a 3 AA Brinkmann, and a 10 watt 2.2 ohm resistor. The resistor is exactly the same size as a AA battery. I mounted a 5 watt cyan Luxeon Star, and 'Ta Da', an extremely bright flashlight!

I did this for a CPF member.

Wayne J.
www.elektrolumens.com

Originally posted by Doug S:
The memory backup 3.6V lithium cells tend to have very low current delivery capabilities, a few mA. Would be OK if you want very low light levels for 100s of hours. No resistor required.

Click to expand...

<font size="2" face="Verdana, Arial">Hmm, I hooked up the two batteries without a resistor, and measured 2.2 amps! Low current? Are we talking about the same batteries?

Wayne J.

Originally posted by ElektroLumens:
</font><blockquote><font size="1" face="Verdana, Arial">quote:</font><hr /><font size="2" face="Verdana, Arial">Originally posted by Doug S:
The memory backup 3.6V lithium cells tend to have very low current delivery capabilities, a few mA. Would be OK if you want very low light levels for 100s of hours. No resistor required.

Click to expand...

<font size="2" face="Verdana, Arial">Hmm, I hooked up the two batteries without a resistor, and measured 2.2 amps! Low current? Are we talking about the same batteries?
Wayne J.</font><hr /></blockquote><font size="2" face="Verdana, Arial">He's talking about the Thionyl Lithium AA that's no way rechargeable...your first post says You used a Li-Ion rechargeable, right?

Lithium ion rechargeable cells are very different from the Saft primary cells. The Saft 14500 primary cells are rated at a maximum discharge current of 25mA, and at that current you've already lost half of your capacity.

Actually, I'd like to know where you got the Lithium-Ion rechargeables in AA size; they would be perfect for a project that I am working on.

-Jon

There are lithium ion cells available from allelectronics.com look up item number BTE-1200

They are 0.72" diameter x 2.56" long, hmm, that sounds bigger around than AA doesn't it? So maybe thats not what you are looking for afterall.

These cells do not have any of the very necessary circuitry attached though. You can't use LiIon cells without it! There is a lot more info on other threads around here, but LiIon cells are very dangerous if used without the protections. At best you'll run them down below their threshold and render them useless and at worst they will catch fire and burn your house down. (pardon if you already know all that

-James

So what would these things do to an Arc-AAA (in an ArcFinity housing)?
Would it just give deplete very quickly or would it ruin the Arc-AAA?

Originally posted by Illuminated:
3.6V lithium battery the size of (1) AA. SAFT part # LS 14500. Maybe a possible candidate for LS mods or super-small "1-cell" LS ? I discovered these in use for some industrial PLC memory backup applications. Think I saw an equivalent battery in Parts Express catalog. Anyone else know anything about these?
John

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<font size="2" face="Verdana, Arial">I checked the datasheet of the SAFT LS14500 specifically. Beware of the "equivalent" ones. The LS14500 actually has better current capability that most AA cells of this chemistry. It looks like it may direct drive a lower Vf luxeon at around 100mA. This may actually be a pretty good, easy mod, giving 20+ hours of reasonable light. Here is a link to the datasheet:
http://www.saftbatteries.com/lithium/e/datasheets/ls1450_1.pdf

Originally posted by Jonathan:
Lithium ion rechargeable cells are very different from the Saft primary cells. The Saft 14500 primary cells are rated at a maximum discharge current of 25mA, and at that current you've already lost half of your capacity.

Actually, I'd like to know where you got the Lithium-Ion rechargeables in AA size; they would be perfect for a project that I am working on.

-Jon

Click to expand...

<font size="2" face="Verdana, Arial">Here's the link for the Li-Ion recharbable AA batteries.

Li-Ion Batteries

Wayne J
www.elektrolumens.com

Wayne (Electro)
Couldn't use the link you provided, -do you have a URL for the AA sized Li-Ion?
Like Jonathan, I'm alsokeenly interested in those cells for an upcoming mod!
Thanks.

I have some Tadiran batteries marked TL-2100 3.6V. I hooked it to a LS and pulled 28ma. Hooked to a Nichia White 5mm, it pulled 10ma.

Originally posted by ElektroLumens:
</font><blockquote><font size="1" face="Verdana, Arial">quote:</font><hr /><font size="2" face="Verdana, Arial">Originally posted by Jonathan:
Lithium ion rechargeable cells are very different from the Saft primary cells. The Saft 14500 primary cells are rated at a maximum discharge current of 25mA, and at that current you've already lost half of your capacity.

Actually, I'd like to know where you got the Lithium-Ion rechargeables in AA size; they would be perfect for a project that I am working on.

-Jon

Click to expand...

<font size="2" face="Verdana, Arial">Here's the link for the Li-Ion recharbable AA batteries.

Li-Ion Batteries

Wayne J
www.elektrolumens.com</font><hr /></blockquote><font size="2" face="Verdana, Arial">I don't see any Li-ion cells at the link provided. Is it the link you intended?

Originally posted by Doug S:
</font><blockquote><font size="1" face="Verdana, Arial">quote:</font><hr /><font size="2" face="Verdana, Arial">Originally posted by ElektroLumens:
</font><blockquote><font size="1" face="Verdana, Arial">quote:</font><hr /><font size="2" face="Verdana, Arial">
Actually, I'd like to know where you got the Lithium-Ion rechargeables in AA size; they would be perfect for a project that I am working on.

-Jon

Click to expand...

<font size="2" face="Verdana, Arial">Here's the link for the Li-Ion recharbable AA batteries. Li-Ion Batteries

Wayne J
www.elektrolumens.com</font><hr /></blockquote><font size="2" face="Verdana, Arial">I don't see any Li-ion cells at the link provided. Is it the link you intended?[/QB]</font><hr /></blockquote><font size="2" face="Verdana, Arial">Not having any luck at all today. Tha alliedelec.com link shows up here as encrypted.....
Went to: www.alliedelec.com , did search all over site and couldn't find anything like that item.

Could this battery be from their new Unobtainium line? This was previously distributed by Vaporware Industries, I believe.

Doug S,
Sounds like you know this Saft computer battery. Might not be good for a barn-burner LS, but an efficient and tiny LS pocket lite that could be impressive...Thanks for checking it out.
John

p.s. Did anyone else wonder if the "LS" part of the battery number meant...

Here is the results for a little test I did back in Mar-Apr of this year that I reported in a thread that started on 4-7-02 in the "Electronics, Batteries Included" Forum.
============
"I put a 3.6v Li AA in an ARC sls and ran it for one hour! Starts off VERY bright and at the end of the hour, I would guestimate that it was about 50%-75%. You could read something close to the light. Plus the flashlight got very warm to the touch. Turn the light off and let it cool down and it comes back to about half bright. Unloaded the battery recovers to almost new voltage. In a real life usage (a little on, a bunch off )the battery might be usefull. At $2.50 a battery, give it a shot! At $10.00 from Radio Shack, I'll not do this again."
===============

It was a TL-2100 Tadiran Li battery.

ADDED:

And here's a runtime plot of a ARC LS with a 3.6v Li battery.

The reason most 2AA computer mem backup packs are current limited to a small current is they have a resistor and a small diode to limit current and voltage. The batteries them selves are 3.6 volts each. The capacity of one alone could replace two of your standard AA alks. If you put two of these in a 2AA device you are talking more power than a alk 4AA device. When you use these in a LED device you need to limit the current to a safe level for the LED and for the battery. If you don't you will run the battery down quickly or even damage your LED.
Lithium have one problem for driving white leds, the 3.6 volt cell voltage is to close to what the led needs. With one cell driving a led the voltage only needs to drop 15% or so and you LS is going to get real dim. With two cells unless you are using a switcher your dropping resistor has to totally waste half the power you are pulling from your batteries. The best way to go with lithium might be to use a step up or a buck boost regulater and a higher ouput cell like a 123. The AA cell would limit you to a lower current than some might like.

Originally posted by carbonsparky:
The reason most 2AA computer mem backup packs are current limited to a small current is they have a resistor and a small diode to limit current and voltage.

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<font size="2" face="Verdana, Arial">For an assembled pack for memory backup, I can see the rational for a blocking diode. I don't see any reason for a resistor to limit current since the current is limited by the high cell resistance that is a consequence of the construction and chemistry.

Originally posted by Doug S:

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<font size="2" face="Verdana, Arial">For an assembled pack for memory backup, I can see the rational for a blocking diode. I don't see any reason for a resistor to limit current since the current is limited by the high cell resistance that is a consequence of the construction and chemistry.[/QB][/QUOTE]

The cell resistance of the AA lithiums is not as low as you imply. The coin cells used in memory backup are in the range you are refering to. That is how photon and others can drive a white led off of two lithium cells with no current limiting resistors.

The resistors are most likely placed in the circuit to protect people from their own mistakes, ie plugged in backwards or in the wrong place. I have not taken every brand of those two AA lithium memory packs apart so I can not say they all have this circuit in them.