What is the attraction of multiple-cell AA lights?

[Disciple]

Re: What is the attraction of multiple-AA lights?

If you're using 18650 lights (or any other lithium rechargeable lights), you'll need to rotate your batteries regularly (to prevent them from swelling).

I am not familiar with this issue. Would you please explain it to me? I have read that storing Lithium Ion cells fully charged causes them to age faster (inquiry) but I haven't heard of swelling. Is swelling a sign of aging? Is there danger in it?

You can always switch over to CR123. But in this case, better use a 1 cell flashlight, to prevent from having a cell reversal incident. The last thing you'd want while bugging out, is being injured or ending up with a damaged light.

As far as I know this problem has not been recurrent with US made CR123A's from the same batch and both new. If you have information to the contrary I want to know because at the moment I am comfortable using US CR123A's in 2 cell lights. (Though I would not use a 2xCR123A headlamp.)

 

[eff]

Re: What is the attraction of multiple-AA lights?

I am not familiar with this issue. Would you please explain it to me? I have read that storing Lithium Ion cells fully charged causes them to age faster (inquiry) but I haven't heard of swelling. Is swelling a sign of aging? Is there danger in it?

This issue can occur when the lithium battery is overcharged, overdischarged. It can also occur on li ion charged up to 100%, and stored for a long period of time. I had some 18650 panasonic red label, that were initially charged to 100%, and I forgot about them for about 1 year or 2 . After this rather long period of time, I decided to check on them. And to my surprise, they had bubbles and there were some small leaks under the plastic package (FYI I have no idea when they started bubbling).

Next time you purchase a brand new 18650, 16340, etc... simply do a battery check with a multimeter. You'll see that you won't get a 4.2v reading (100% charged) but rather a value around 3.75-3.8 volt, which indicates that your battery has been charged for storage (40%-60%).

I'm not 100% sure there's some danger to this bubbling/swelling issue. I did not have any venting w/ flame.

As far as I know this problem has not been recurrent with US made CR123A's from the same batch and both new. If you have information to the contrary I want to know because at the moment I am comfortable using US CR123A's in 2 cell lights. (Though I would not use a 2xCR123A headlamp.)

Here's some info on cell reversal : http://en.wikipedia.org/wiki/Rechargeable_battery
I never had a cell reversal incident, but rather got my information from cpf threads.
Here's a a link to one of these incident (I think the guy was using CR123 cells from Surefire) :
http://www.candlepowerforums.com/vb...6-123-Primary-Lithium-cell-info-testing-links


I'm not dissing the lithium technology (I do have a few 18650, CR123 lights). But after my bubbling batteries incident, I decided to charge my lithium cells to only 50%, and rely mostly on AA and AAA when I'm not at home.

 

[mcnair55]

Re: What is the attraction of multiple-AA lights?

@eff

Buying and running a light should be a pleasurable experience,i should not have to check voltages with volt meters and all that other geeky stuff.If i buy an 18650 light this afternoon from Maplins in the UK there will be no talk of telling me i need to buy a volt meter.

I just want to use it and enjoy it and not think of it as an Exocet missile as the anorak crowd do,sometimes people spoil there own hobby for no real reason,surely common sense is order of the day.

 

[eff]

Re: What is the attraction of multiple-AA lights?

@eff

Buying and running a light should be a pleasurable experience,i should not have to check voltages with volt meters and all that other geeky stuff.If i buy an 18650 light this afternoon from Maplins in the UK there will be no talk of telling me i need to buy a volt meter.

I just want to use it and enjoy it and not think of it as an Exocet missile as the anorak crowd do,sometimes people spoil there own hobby for no real reason,surely common sense is order of the day.

I did not want to spoil anybody's experience with li ion flashlights. I simply replied to Disciple's questions. That's all.

 

[dc38]

Re: What is the attraction of multiple-AA lights?

@eff


Buying and running a light should be a pleasurable experience,i should not have to check voltages with volt meters and all that other geeky stuff.If i buy an 18650 light this afternoon from Maplins in the UK there will be no talk of telling me i need to buy a volt meter.


I just want to use it and enjoy it and not think of it as an Exocet missile as the anorak crowd do,sometimes people spoil there own hobby for no real reason,surely common sense is order of the day.

ID like to think that every hobby has a level of responsibility and pride involved, and flashaholism is no exception. That's why we try to buy the best we can afford. Hobby chargers, power cells, even grease and lube! There's an inherent joy when you sit down to a personal evaluation of your equipment to check for consistency and reliability, much like a good boss does with his employees. The more you get to know your gear, the more comfortable you will become using them. You will not only learn their quirks and their strengths, but their personalities as well. Should anybody assume that the user experience is "ruined" by meticulous attention to our lights, they could not be more wrong. Especially with abused gear(combat tested and proven) and specialized cells, the most reliable troopers need a few check ups to ensure they are in good operating order.

 

[gravelmonkey]

Re: What is the attraction of multiple-AA lights?

@eff

Buying and running a light should be a pleasurable experience,i should not have to check voltages with volt meters and all that other geeky stuff.If i buy an 18650 light this afternoon from Maplins in the UK there will be no talk of telling me i need to buy a volt meter.

I just want to use it and enjoy it and not think of it as an Exocet missile as the anorak crowd do,sometimes people spoil there own hobby for no real reason,surely common sense is order of the day.

So angry! No-one's forcing you to measure voltages, it's just common sense . If you just want that fit and forget approach, why not just use multiple NiMh AA's?

Single cell light, good quality 18650's and a decent charger are pretty safe combination, I'm not quite sure it is completely 'idiot proof' consumer tech though.

Multiple 18650 lights, especially with unprotected cells NEED measuring unless you're desperate for a trip to A&E or worse... It's not a missile, just a pipe bomb.

 

[Disciple]

Re: What is the attraction of multiple-AA lights?

eff, thank you. Serious stuff to think about.

mcnair55, I don't believe you need to check cell voltage for use in a single-cell 18650 light, which is most common. If I understood the charging-in-parallel thread correctly parallel 18650 configurations should also be pretty safe. Some chargers such as the Xtar VP1 that I have include voltage meters now. And I guess I have to ask: what do you mean by "anorak crowd" anyway?

 

[cerbie]

Re: What is the attraction of multiple-AA lights?

How often does this practically result in a superior light?

How often does it result in an inferior light? Only during extended power outages do I ever find the total energy in the battery to matter, and my solution for that is spare cells. When a single charge won't do, spare cells include charged rechargeables.

Can you point to a case where this results in a superior form factor?

Any time someone buys 2xAA flashlight, in part for the thinness of the body? If you don't have pockets made for tools (all of my pants do ), CR123 can be just a bit too wide, compared to slim AA bodies. Or, in the case of soup can or box shapes, they might fit in the hand better, for some. Just as I find 25-30mm bodies to be about right for my hand, others find wider, or thinner, or flash/flat shapes, etc..

Given the especially poor performance of alkaline batteries in cold weather I think I'd reach for just about anything else.

Like Lithium AAs? Even in the South, in barely freezing temperatures, I've had alkalines and NIMHs fail me, but then be fine after arming up. Lithium types also perform poorly in cold weather, but they do perform.

I find it hard to believe that anyone planning for a "Katrina" would plan on running to the store to scrap for batteries, or raiding remote controls and toys for that matter. If you are planning ahead lay in a supply!

AAs, AAAs, and 9Vs will be gone ASAP. I've seen itself, with the forecast only having a small chance of a tail of a hurricane coming in, before. What you (and family and neighbors) have at home is what you'll have to work with. Scavenging from remotes I have done, and will do again, before using new cells. Part of the thing there is that AAs can feed multiple devices, so you can have one large stash, big enough to handle days without power, but small enough to go through before they become out of date.

As acknowledged a common battery for all devices is a powerful incentive. I am apparently the oddball not owning AA devices. (Don't most cameras have Lithium Polymer packs now?)

Yes, quite the oddball in that. Most cameras use their own proprietary batteries, but they are still readily available using AAs, and those that use AA NIMH for their cameras often don't even consider any other power source, now that they are accustomed to it.

 

[samgab]

Re: What is the attraction of multiple-AA lights?

...

As acknowledged a common battery for all devices is a powerful incentive. I am apparently the oddball not owning AA devices. (Don't most cameras have Lithium Polymer packs now?)

Yes, quite the oddball in that. Most cameras use their own proprietary batteries, but they are still readily available using AAs, and those that use AA NIMH for their cameras often don't even consider any other power source, now that they are accustomed to it.

Just one point further to the above, many people who use the kind of DSLR cameras that use Li-ion battery packs also use additional flash/es, many of which use multiple AA's (and NiMH cells are the fuel of choice for those too, because they suck current in high bursts, and use a lot of energy. So many of the subset of camera users that have cameras that don't use AA's are still big users of NiMH AA's for this reason). So they'd also have a store of spare, charged AA cells - usable in a multi-AA flashlight in a time of need.

 

[Poppy]

Re: What is the attraction of multiple-AA lights?

Originally Posted by Disciple I am not familiar with this issue. Would you please explain it to me? I have read that storing Lithium Ion cells fully charged causes them to age faster (inquiry) but I haven't heard of swelling. Is swelling a sign of aging? Is there danger in it?

This issue can occur when the lithium battery is overcharged, overdischarged. It can also occur on li ion charged up to 100%, and stored for a long period of time. I had some 18650 panasonic red label, that were initially charged to 100%, and I forgot about them for about 1 year or 2 . After this rather long period of time, I decided to check on them. And to my surprise, they had bubbles and there were some small leaks under the plastic package (FYI I have no idea when they started bubbling).

Next time you purchase a brand new 18650, 16340, etc... simply do a battery check with a multimeter. You'll see that you won't get a 4.2v reading (100% charged) but rather a value around 3.75-3.8 volt, which indicates that your battery has been charged for storage (40%-60%).

I'm not 100% sure there's some danger to this bubbling/swelling issue. I did not have any venting w/ flame.



Here's some info on cell reversal : http://en.wikipedia.org/wiki/Rechargeable_battery
I never had a cell reversal incident, but rather got my information from cpf threads.
Here's a a link to one of these incident (I think the guy was using CR123 cells from Surefire) :
http://www.candlepowerforums.com/vb...6-123-Primary-Lithium-cell-info-testing-links


I'm not dissing the lithium technology (I do have a few 18650, CR123 lights). But after my bubbling batteries incident, I decided to charge my lithium cells to only 50%, and rely mostly on AA and AAA when I'm not at home.

I read through much of the material at Battery University regarding Li-Ion cells, and I agree with Disciple's comment above. One of the factors leading to aging is the average percentage of charge they are stored and used at. Nothing was mentioned at Battery U, nor on the wiki linked to above, that storing a battery fully charged will lead to battery damage. eff admits "(FYI I have no idea when they started bubbling)" I'd like to suggest that they were most likely damaged prior to being put away.

Cell reversal type Battery damage occurs from over discharging a battery, typically by way of putting them into a charger backwards, or by having unmatched cells in series, (like in multi-cell lights).

Most of the fire incidents listed in the CPF battery section are of CR123's in flashlights in series. OR they were purposefully over-discharged as part of an experiment. IIRC most of those threads are from 2006, or earlier.

Next time you purchase a brand new 18650, 16340, etc... simply do a battery check with a multimeter. You'll see that you won't get a 4.2v reading (100% charged) but rather a value around 3.75-3.8 volt, which indicates that your battery has been charged for storage (40%-60%).

Storing at 40%-60% is to maximize the battery life.

I store mine at about 90% charge. I want them ready to go when I need them.

 

[samgab]

Re: What is the attraction of multiple-AA lights?

...Storing at 40%-60% is to maximize the battery life.

I store mine at about 90% charge. I want them ready to go when I need them.

Very good common sense approach. What's the use of a cell that lasts for years and years but can't be used at the moments you need it? I'd also rather take a small hit on longevity of cells for the functionality of them being instantly ready to go when I need them.

 

[Poppy]

Re: What is the attraction of multiple-AA lights?

Disciple,
I want to thank you for starting this thread.
At first I thought it was a trolling thread, but you convinced me otherwise.

After reading the first 30 posts or so, I softened my position on multi-cell AA lights. However, so many people missed the point, which was... why?, 4 cell - 6 cell or 8 cell AA lights, and went on and on about the wonders of the AA battery, and its energy sipping single and dual cell lights, and having the ability to scavenge partially depleted cells from toys, radios, and walkie-talkies; that I took a second look at my AA/18650 battery strategy.

I have, I think, 20 made in China, NiMH AA's. They self discharge and are of low capacity. Not impressive
Reading here of the quality of Eneloops, I bought 16 AAs, and 8 AAAs. (when I find them on sale, I'll buy more)

My quality AAA is a Thrunite Ti (single cell)
My quality AA is a 2 cell Mini Maglight LED 2 mode with blinkies.
I also have a few cheap 2 AA rayovacs.

I also have head lamps of the AA, AAA, and 18650 variety.

The eneloops, while impressive are in various states of discharge all over the house. I'm not even sure where they all are. I do have four fully charged ones in a drawer in my desk. In the event of a power outage, I wouldn't want to have to go around the house, pulling toys apart, or remotes, etc, looking for them.

On the other hand, I have 17* 18650 batteries @ ~ 90% charge, and I know where each and every one of them is.

 

[Disciple]

Re: What is the attraction of multiple-AA lights?

How often does it result in an inferior light? Only during extended power outages do I ever find the total energy in the battery to matter, and my solution for that is spare cells. When a single charge won't do, spare cells include charged rechargeables.

You never run down a set of cells in normal use? I find that surprising. Do you usually avoid using the "high" mode on your lights? If so why not choose a smaller, lighter one for the task at hand?

Any time someone buys 2xAA flashlight, in part for the thinness of the body? If you don't have pockets made for tools (all of my pants do ), CR123 can be just a bit too wide, compared to slim AA bodies. Or, in the case of soup can or box shapes, they might fit in the hand better, for some. Just as I find 25-30mm bodies to be about right for my hand, others find wider, or thinner, or flash/flat shapes, etc.

Another gap in my collection I suppose. The classic Mini Mag is a nice size, but not really much different from slim 2xCR123A 18650 torches in use. I don't have any 1xAA lights in my collection at the moment, but the ones I've handled seemed no more convenient than CR123A lights. AAA is in a different class of course.

Like Lithium AAs? Even in the South, in barely freezing temperatures, I've had alkalines and NIMHs fail me, but then be fine after arming up. Lithium types also perform poorly in cold weather, but they do perform.

I really like the L91 lithium AA's. As a result of this thread I intend to get a supply of those.

Disciple,
I want to thank you for starting this thread.
At first I thought it was a trolling thread, but you convinced me otherwise.

You're welcome. As stated I don't troll, and I have learned a lot from it.

Do you worry about the lifespan of those 17 18650's? Should they last only 3-4 years at your chosen charge level are you prepared to replace them that often?

 

[eff]

Re: What is the attraction of multiple-AA lights?

I read through much of the material at Battery University regarding Li-Ion cells, and I agree with Disciple's comment above. One of the factors leading to aging is the average percentage of charge they are stored and used at. Nothing was mentioned at Battery U, nor on the wiki linked to above, that storing a battery fully charged will lead to battery damage. eff admits "(FYI I have no idea when they started bubbling)" I'd like to suggest that they were most likely damaged prior to being put away.

No way to know if they've been damaged at some point before storage, even though they've always been treated gently, and have always worked perfectly.
I agree there's not much data on the web regarding 100% charged lithium batteries, that have been stored away for a long time.
The only information I could dig on the subject was a video posted on youtube.
The video was posted by a retired engineer in N-Z, doing RC models. The video is about LIPOs (storage explanation starts at 12:00, and fully charged lipo info at 13:40). Here's the link : http://www.youtube.com/watch?v=ZJHlJYDJohc

The information given in the video did match what I did and what happened to my 18650s.

 

[mcnair55]

Re: What is the attraction of multiple-AA lights?

eff, thank you. Serious stuff to think about.

mcnair55, I don't believe you need to check cell voltage for use in a single-cell 18650 light, which is most common. If I understood the charging-in-parallel thread correctly parallel 18650 configurations should also be pretty safe. Some chargers such as the Xtar VP1 that I have include voltage meters now. And I guess I have to ask: what do you mean by "anorak crowd" anyway?

The anorak crowd my dear chap is you me and other members of any specialist hobby board,we all go so deep into the hobby we clinically examine everything we do and read.Grease and lube for example,you need a first class honours degree to understand it. When you think about it all you need is a decent lube that is o ring and electrical safe nothing more and nothing less yet you will read countless threads recommend this that and the other,all very confusing for the newbie.

How often do you read the guy nipping out shopping and armed to the teeth with an edc and three back up lights,he is going to buy groceries not on the next covert ops mission in the desert.

Anoraks and i include myself.

 

[Disciple]

Re: What is the attraction of multiple-AA lights?

Here's the link : http://www.youtube.com/watch?v=ZJHlJYDJohc

The information given in the video did match what I did and what happened to my 18650s.

Interesting, but for now I'll still keep my cells at about 90%. We'll see what happens. :sweat:

 

[Disciple]

Re: What is the attraction of multiple-AA lights?

The anorak crowd my dear chap is you me and other members of any specialist hobby board.

Got it. I like to "geek out" on stuff; what can I say.

 

[reppans]

What is the attraction of multiple-AA lights?

Regarding Li-ion charging and storing -

I always found this military study of different charging habits to be very useful, and it does support Battery University findings as well. While it doesn't exactly address storage, I consider average state of charge during long term usage to be a fair proxy. The big Li-ion killers I takeaway from the chart and BU, in order, are:

- maintaining higher average states of charge
- charging to 100%
- deeper charge/discharge cycles
- and of course the usual # of cycles/age thing.

I don't care as much about flashlight batts since they're relatively cheap and easily replaced, but I do closely manage charging on my smartphone/tablet that have non-removable batteries, and more frequent cycling. I use a light timer to cycle on a 70-30-70 basis (since I average 40% per day) and set it to start charging on an hour or 2 before I wake.

 

[Poppy]

Re: What is the attraction of multiple-AA lights?

Do you worry about the lifespan of those 17 18650's? Should they last only 3-4 years at your chosen charge level are you prepared to replace them that often?

The percent charge is only ONE of four categories of things that kill a cell, the others being AGE, TEMPERATURE/HEAT, and charge cycles. I believe that heat is the most destructive, coupled with percent charge. I keep my cells in storage in the refrigerator.


eff,
That was an interesting video, thanks for presenting it. I'd like to point out that cells for R/C flying are typically LiPO cells, because in part, they are lighter. Their chemistry is a little bit different from the typical 18650 battery, and therefore the statements in the video are not necessarily directly transferable.... maybe. I really don't know.

 

[Disciple]

Re: What is the attraction of multiple-AA lights?

So I guess the discussion comes down to this:
Do you have extra cells that you can store that you can charge up:
1. in anticipation of an impending event (such as a predicted hurricane), or,
2. even in the event of an unexpected outage, you can charge them while using those that are in your daily rotation?
Again, I am assuming that you have a car charger for those cells that are in long term storage, so that they can be charged when the grid is down.

No offense intended but I suggest you take this to a new thread as it is off topic for mine. I'd like to keep this one concise enough to be useful to future readers.