Lithium AAs

These forums are opening my eyes to just how much information and choice there is in the world of flashlights.

I am keen on using AAs for several reasons, including having several AA flashlights and a good stock of batteries.

I have been using the lithium AAs for a while in a digital camera and find their light weight and high capacity really good.

There may be a lot of alarm-ism on this forum, or there may be a good foundation for some comments I have read, but there seems to be some lack of trust in the lithium AA especially when more than one is needed.

The first candidate to go from alkaline to lithium AAs is my terraLUXed mini maglite. As long as I always use new batteries together is there any reason to be afraid of lithium AAs?

When looking for disposable AAs what is the best choice?

( I do always use rechargeable when possible, but for standby lights or time away from chargers I want to know the best choices)

The concerns about lithium cells are with the li-ion rechargeables. Why to use them if they can be dangerous? Because their energy density is, as far as I know, unsurpassed for "easy" to get cells.

Energizer Lithiums are, in my opinion, considered safe and great for backup. They would be even better if they were cheaper. The only big concern is their voltage is a bit over the typicall alkaline, and some devices can be fried because of this (specially in multi-cell devices).

You're talking about two different types of Lithium battery.

Lithium primaries, which are non-rechargeable, are generally considered very safe. I've never heard of any problems with Lithium AA/AAA, and only very few problems with CR123 (mostly caused by mixing old and new cells, or sudden shorts). For the neumber of batteries that have been produced, and th enumber of incidents there have been, the risk with primary lithium is virtually nil.

And

Lithium ion, or Li-ion, for short. These are a type of rechargeable battery. They require more maintenance and care in use, and espcially while charging. There are many different chemistries, some "riskier," but higher capacity, and some safer, but lower capacity. These are not a direct replacement for the lithium primaries above. They generally have a much higher voltage, especially when charged (3.6-4.2v versus 1.7/3.0v for primary). Most lights, and other things are meant to use lithium primary only, and may not support the higher voltages of a Li-ion cell. You have to be very attentive to the conditions these cells have been used in. They do not like extreme temps, either hot or cold, most chemistries can only safely handle a few C's of discharge or charge current (ie: 2200mA 18650 Li-ion: 2C current draw would be 4400mA, etc.). If damaged, a cells chance of venting with flame is greatly increased.

Lithium primary come in a few types/sizes. I've heard of Lithium AA, AAA, D, and CR123 (I may have missed a few types). These are meant to be a direct replacement for alkaline primary, but usually have a higher voltage (1.7/8 versus 1.5).

Lithium-ion come in certain sizes, and are usually represented by a series of numbers. IE: 16340, 18650, 17650, 18500, etc.

Example: 16340

the first two digits represent the diameter of the cell. In the case above, 16millimeters.

The second two digits represent the overall length. In the above example, 34millimeters.

The last digit represents shape. The "0" represents round, ie: cylindrical.

These numbers are generally considered accurate, but, as with all things, can vary from manufacturer to manufacturer slightly.

An item that many consider necessary when using Li-ion is a protection circuit. This is often reffered to as a "protected cell", meaning it has a samll circuit board, usually at the positive contact, that keeps track of the cells voltage. If the current draw is so high it's unsafe, or if the cell is discharged below a certain point (usually 3.6/7v), the circuit will trip, stopping any current draw from the cell. These protection circuits are not 100% effective, and can be damaged, so careful maintenance of Li-ion cells is necessary.

Hope this helps allay some of your fears. Lithium batteries are really superior to other primary chemistries, such as alkaline, and are worth the expense, IMO.

Thanks for your comments.

I was specifically asking about the Lithium primary type in the AA size. I had read some comments that distrusted these, so was confused as I had always felt they were an excellent battery. To my knowledge there is no Li-ion in AA size.

You have confirmed resoundingly that the AA or AAA lithium 'primary' is very reliable and an excellent choice.

As for Li-ion:

well I agree with the comments about being careful and that they are the best performance for the money.

Protected or not, surely the problems are caused by abuse, by driving them too hard when powering ultra high power lights.

If you are not working on the forefront with the most high power emitters but instead work well within the design limits, even cheap unprotected cells should not offer any danger.

If you are running an expensive ultra performance emitter configuration then it will make sense to buy protected cells, but at the medium or even highish performance levels I think that a bit of common sense means you could safely use the cheapy chinese li-ions.

I am definitely in favour of really good value for money and think that a few horror stories which are the result of poorly thought out configurations lead to the general mistrust of a perfectly usable source of components and the over inflation of the need to run more expensive protected batteries.

John_Galt said:

Lithium primary come in a few types/sizes. I've heard of Lithium AA, AAA, D, and CR123 (I may have missed a few types). These are meant to be a direct replacement for alkaline primary, but usually have a higher voltage (1.7/8 versus 1.5).

.

Click to expand...

The AA and AAA lithium primary cells made by energiser do indeed have a voltage a little higher than alkalines, and can be used instead of alkalines in most, but not all appliances.

However I have never seen a D size lithium primary in this voltage, suitable for replacing an alkaline.
Is the above post a typo ? or does the O/P know something that most of us dont.
D size lithiums certainly exist, I have some, but AFAIK they come only in 3.7 volt, not in 1.7.

subwoofer said:

Thanks for your comments.

I was specifically asking about the Lithium primary type in the AA size. I had read some comments that distrusted these, so was confused as I had always felt they were an excellent battery. To my knowledge there is no Li-ion in AA size.

You have confirmed resoundingly that the AA or AAA lithium 'primary' is very reliable and an excellent choice.

As for Li-ion:

well I agree with the comments about being careful and that they are the best performance for the money.

Protected or not, surely the problems are caused by abuse, by driving them too hard when powering ultra high power lights.

If you are not working on the forefront with the most high power emitters but instead work well within the design limits, even cheap unprotected cells should not offer any danger.

If you are running an expensive ultra performance emitter configuration then it will make sense to buy protected cells, but at the medium or even highish performance levels I think that a bit of common sense means you could safely use the cheapy chinese li-ions.

I am definitely in favour of really good value for money and think that a few horror stories which are the result of poorly thought out configurations lead to the general mistrust of a perfectly usable source of components and the over inflation of the need to run more expensive protected batteries.

Click to expand...

Actually, there is. It's the 14500

Ah-ha, but it is a very different battery and I should have chosen my words more carefully.

What I meant to say was that, to my knowledge, there is no Li-ion AA, there is NiMh, Ni-cd, Lithium primary or alkaline etc, but no Li-ion.

Doesn't the AA indicate a standard where the voltage is around the 1.5V (1.2-1.7V) with specific size, shape etc?

If I said a CR123, it would not mean a RCR123 or 16340 it would mean a CR123. Just as when I say AA I don't mean something else.

Anyway I/we are digressing...

Lithium ion cells are 3.7 volts, and about 4.2 volts when fresh off the charger. If you are wondering if there is a Li-ion replacement for any primary cell, first determine if a 3.7-4.2 V cell (or some multiple of that) is acceptable for your particular application.

Some 2xCR123A devices can take a 17670 or 18650 cell, if the device can handle the lower voltage. Some 1xCR123A devices can take the higher voltage of the RCR123A.

Not many 1xAA devices can handle a 14500 Li-ion cell. The Quark AA can, and it gives a much higher output in this configuration also.

subwoofer said:

Ah-ha, but it is a very different battery and I should have chosen my words more carefully.

What I meant to say was that, to my knowledge, there is no Li-ion AA, there is NiMh, Ni-cd, Lithium primary or alkaline etc, but no Li-ion.

Doesn't the AA indicate a standard where the voltage is around the 1.5V (1.2-1.7V) with specific size, shape etc?

If I said a CR123, it would not mean a RCR123 or 16340 it would mean a CR123. Just as when I say AA I don't mean something else.

Anyway I/we are digressing...

Click to expand...

In short, 10440 and 14500 are "AAA sized" and "AA sized." If you use these lithium-ion cells in something that won't handle the voltage (4.2v fresh off the charger!) and extra heat (up to 2.8x the current), you'll toast it. The AA battery was originally ~1.5v alkaline or zinc-oxide, later NiCd and NiMH were added and are accepted, despite having slightly different voltages. Energizer lithiums are close enough in voltage that they rarely cause problems, so they've been tacked onto the 'AA/AAA' format as well. 10440 and 14500 require real thought before use, even in reasonably-designed electronics. That's the tricky part, really...'AA' and 'AAA' are essentially just a size these days, with all the chemistries (5?) that count.

It's true that "A", "AA", "C", "D" "F" etc. are specific sizes, regardless of the cell's chemistry. Generally though, the letter sizes seem to be used for non lithium (both primary and secondary) cells, and the numerical size designations used for lithium cells. There is no rule however, so you see it both ways sometimes, especially when it comes to battery pack cells. There you will see "18650" NiMH cells and such, quite often.

Dave

John_Galt said:

You're talking about two different types of Lithium battery.

Lithium primaries, which are non-rechargeable, are generally considered very safe. I've never heard of any problems with Lithium AA/AAA, and only very few problems with CR123 (mostly caused by mixing old and new cells, or sudden shorts). For the neumber of batteries that have been produced, and th enumber of incidents there have been, the risk with primary lithium is virtually nil.

And

Lithium ion, or Li-ion, for short. These are a type of rechargeable battery. They require more maintenance and care in use, and espcially while charging. There are many different chemistries, some "riskier," but higher capacity, and some safer, but lower capacity. These are not a direct replacement for the lithium primaries above. They generally have a much higher voltage, especially when charged (3.6-4.2v versus 1.7/3.0v for primary). Most lights, and other things are meant to use lithium primary only, and may not support the higher voltages of a Li-ion cell. You have to be very attentive to the conditions these cells have been used in. They do not like extreme temps, either hot or cold, most chemistries can only safely handle a few C's of discharge or charge current (ie: 2200mA 18650 Li-ion: 2C current draw would be 4400mA, etc.). If damaged, a cells chance of venting with flame is greatly increased.

Lithium primary come in a few types/sizes. I've heard of Lithium AA, AAA, D, and CR123 (I may have missed a few types). These are meant to be a direct replacement for alkaline primary, but usually have a higher voltage (1.7/8 versus 1.5).

Lithium-ion come in certain sizes, and are usually represented by a series of numbers. IE: 16340, 18650, 17650, 18500, etc.

Example: 16340

the first two digits represent the diameter of the cell. In the case above, 16millimeters.

The second two digits represent the overall length. In the above example, 34millimeters.

The last digit represents shape. The "0" represents round, ie: cylindrical.

These numbers are generally considered accurate, but, as with all things, can vary from manufacturer to manufacturer slightly.

An item that many consider necessary when using Li-ion is a protection circuit. This is often reffered to as a "protected cell", meaning it has a samll circuit board, usually at the positive contact, that keeps track of the cells voltage. If the current draw is so high it's unsafe, or if the cell is discharged below a certain point (usually 3.6/7v), the circuit will trip, stopping any current draw from the cell. These protection circuits are not 100% effective, and can be damaged, so careful maintenance of Li-ion cells is necessary.

Hope this helps allay some of your fears. Lithium batteries are really superior to other primary chemistries, such as alkaline, and are worth the expense, IMO.

Click to expand...

Very good info for the OP, but I would disagree on one point and that is the volatility of CR123s. As far the dangers of multiple cell use, I would also say that I've heard of more 'mishaps' with primary 123s than Li-Ion. I've personally had a 2 cell light explode with CR123s.

You completely covered the potential problems with their (mis) use, but I'd like to draw more of a distinction between 123 and AA primaries as far as 'safety.' There seem to be no dangers with the AA, and while the numbers are probably smaller than the alarmists would like, there are very real non remote dangers with the CR123s.

I choose single cell lights to avoid problems. I may have six multi cell lights out of dozens. I don't even like multi cell primary lights because there always seems to be at least one cell that discharges unevenly.

subwoofer said:

Ah-ha, but it is a very different battery and I should have chosen my words more carefully.

What I meant to say was that, to my knowledge, there is no Li-ion AA, there is NiMh, Ni-cd, Lithium primary or alkaline etc, but no Li-ion.

Doesn't the AA indicate a standard where the voltage is around the 1.5V (1.2-1.7V) with specific size, shape etc?

If I said a CR123, it would not mean a RCR123 or 16340 it would mean a CR123. Just as when I say AA I don't mean something else.

Anyway I/we are digressing...

Click to expand...

I would probably suggest that you adapt to the thinking of the AA reference as a reference to size, rather than chemistry, although I completely understand your rationale.

I think of lights in terms of cell size and then consider what chemistry they will support.

As to your OP, I think the AA and AAA lithium primaries are exceptional cells. I do pick and choose where I use them because of their cost. For example, I wouldn't use them in a low drain remote. By the same token, I wouldn't use rechargeables in one either, though many here report that they do. I can't see tying up $2-3 cells and worrying about over discharging and ruining them, when 20¢ alkalines will last for at least 3-4 years in them.

I tend to use rechargeables in things like headlights that I use for more extended periods and Li-Ions I use because of their increased light output just as much as their recharging capability.

Re: Lithium AAs...and NiZn

Don't overlook the newest member of the AA club: nickel-zinc, or NiZn, made by PowerGenix. Think of them as the rechargeable alternative to lithium primary AAs:

• Like lithium AAs, Nizn AAs deliver at least 1.6V under a 1A load.
• Like lithium AAs, Nizn AAs hold their voltage well under a 2A load.
• Like lithium AAs, Nizn AAs hold their voltage and capacity in cold temperatures.

They're also dirt-cheap at about $2.50 a cell.

There are three chief downsides:

• They lose about 8 percent of their charge per month.
• At 1400 to 1600mAh, they hold fewer amp-hours than NiMH AA cells.
• They require a special charger, made by PowerGenix.

PowerGenix AA cells and chargers (1-hour or 3-to-5-hour) are available from several vendors on Amazon and eBay.

I'm looking forward to the next generation of NiZn cells. They are already pretty close to high capacity NiMh cells in watt hours, as I rarely see any NiMh cells get much over 2500mAh's anyways.

kitelights said:

As to your OP, I think the AA and AAA lithium primaries are exceptional cells. I do pick and choose where I use them because of their cost. For example, I wouldn't use them in a low drain remote. By the same token, I wouldn't use rechargeables in one either, though many here report that they do. I can't see tying up $2-3 cells and worrying about over discharging and ruining them, when 20¢ alkalines will last for at least 3-4 years in them.

Click to expand...

20 cents doesn't pay for the hassle of that cheap alkaline ruining your remote or portable device or flashlight. Even if the battery company agrees to replace it, it may take weeks to get the money and find another one and factory remotes for most things have to be ordered and mailed to you. I took batteries out of all remotes I don't use more than once in 6 months. I forgot to check the backup batteries in my stereo they had leaked in it and I wished I had put lithiums in it now as the stereo is irreplaceable.

You have a special case there...if something's irreplaceable, you wouldn't want to keep any kind of battery in there for long periods of time.

Generally, leaking alkalines don't do too much damage unless left unattended. If they're leaking, it's usually because they are getting low, and you should be able to notice it before it gets much worse. There's really no reason to use expensive batteries in cheap devices such as remotes, which are actually pretty hard to damage with leaky alkalines. At the very most, I would use NiMH, but never lithium primary.

Besides the cost, lithium primaries are not compatible with all devices. The extra voltage may damage voltage-sensitive devices. Flashlights won't mind, especially two-cell ones, which benefit a lot from the extra voltage unlike three-cell lights, but not everything is regulated that well.


I use a mix of alkaline, lithium primary, and NiMH. Each type serves its own purpose, and here's my take on batteries (of the AA type)...

• Alkaline
  • Pro: Cheap and disposable
  • Con: Potential to leak
  • Verdict: Use in non-critical devices
• Lithium Primary
  • Pro: Higher voltage, lightweight, long-lasting
  • Con: Higher voltage, expensive, potentially dangerous in multi-cell configurations if drained unevenly
  • Verdict: Use for emergency or occasional use devices
• NiMH
  • Pro: Rechargeable, fairly cheap, easy to maintain, safe
  • Con: Heavy, lower voltage, self-discharge
  • Verdict: For frequently used devices
• NiZn
  • Pro: Rechargeable, higher voltage
  • Con: Expensive (compared to NiMH), proprietary
  • Verdict: For specialized applications

Robin24k said:

You have a special case there...if something's irreplaceable, you wouldn't want to keep any kind of battery in there for long periods of time.

Generally, leaking alkalines don't do too much damage unless left unattended. If they're leaking, it's usually because they are getting low, and you should be able to notice it before it gets much worse. There's really no reason to use expensive batteries in cheap devices such as remotes, which are actually pretty hard to damage with leaky alkalines. At the very most, I would use NiMH, but never lithium primary.

Besides the cost, lithium primaries are not compatible with all devices. The extra voltage may damage voltage-sensitive devices. Flashlights won't mind, especially two-cell ones, which benefit a lot from the extra voltage unlike three-cell lights, but not everything is regulated that well.

Click to expand...

This thread should explain my position on alkalines
https://www.candlepowerforums.com/threads/218653

Re: Lithium AAs...and NiZn

Paul_in_Maryland said:

Don't overlook the newest member of the AA club: nickel-zinc, or NiZn, made by PowerGenix. Think of them as the rechargeable alternative to lithium primary AAs:

• Like lithium AAs, Nizn AAs deliver at least 1.6V under a 1A load.
• Like lithium AAs, Nizn AAs hold their voltage well under a 2A load.
• Like lithium AAs, Nizn AAs hold their voltage and capacity in cold temperatures.

They're also dirt-cheap at about $2.50 a cell.

There are three chief downsides:

• They lose about 8 percent of their charge per month.
• At 1400 to 1600mAh, they hold fewer amp-hours than NiMH AA cells.
• They require a special charger, made by PowerGenix.

PowerGenix AA cells and chargers (1-hour or 3-to-5-hour) are available from several vendors on Amazon and eBay.

Click to expand...

These look interesting. How do they compare to Eneloop NiMh AA's? Do they bridge the gap between primaries and Li Ions(14500)?

Also when you say 1 hour or 3 to 5 hour, does that refer to the charge times? Is there any particular reason to choose one over the other?

Robin24k said:

• NiMH
  • Pro: Rechargeable, fairly cheap, easy to maintain, safe
  • Con: Heavy, lower voltage, self-discharge
  • Verdict: For frequently used devices

Click to expand...

That con is easy to get rid of just using LSD cells.

Re: NiZn vs. Eneloop (was: Lithium AAs...and NiZn)

Southpaw1969 said:

These look interesting. How do they compare to Eneloop NiMh AA's?

Click to expand...

I've replaced my 12 Eneloops with 12 nickel-zincs; my Eneloops have been retired to remote controls and camera gear.

Using NiZn AAs, my lights look a bit brighter (sometimes more than a bit), even though all my emitters are regulated. I may need to recharge a bit more often, but it's hard to say whether that's because of their worse capacity or the worse self-discharge rate. On the other hand, because the voltage is higher, the LED's buck regulator needn't work so hard, so it's more efficient; I gain back in electronic efficiency what I lose in self-discharge and lower capacity.

You'll need to make sure your drop-in can handle the oddball voltage total: 1.6-1.7V, 3.2-3.4V, or 4.8-5V. If a drop-in is rated for 3.6 to 4.2V, you're out of luck.

Southpaw1969 said:

Do they bridge the gap between primaries and Li Ions(14500)?

Click to expand...

in voltage, definitely. In effect, you get 4AA voltage in a 3AA package.

Southpaw1969 said:

Also when you say 1 hour or 3 to 5 hour, does that refer to the charge times? Is there any particular reason to choose one over the other?

Click to expand...

Yes, charge time. Choose the 1-hour charger: it lets you charge 1, 2, 3, or 4 cells at a time, not just 2 or 4. Beware: The sellers--and, I think, the packaging--confuse the two chargers. As I recall, "quick charger" = the better, 1-hour charger; "fast charger' = the 3-5 hour charger. To be safe, look for "1 hour." I think the black charger is always the slower charger.