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BackBlast
04-12-2009, 09:29 AM
AA NiMH Hi-Capacity (2500+ mah): 250 cycle life span. Temp range: 20F or higher
AA NiMH Standard (1800-2100 mah): 500 cycle life span. Temp range: 20F or higher.
AA NiMH Low Self Discharge (2000-2100 mah): 500 cycle life span. Temp range -10F or higher.
AA NiCD Hi-Capacity (800-1000 mah): 700 cycle life span. Temp range -20F or higher.
AA NiCD Standard (500-700 mah): 2000 cycle life span. Temp range -20F or higher.
AA Heavy Duty: 1 time use. Temp range: 32F or higher.
AA Alkaline: 1 time use. Temp range: 32F or higher.
AA Lithium: 1 time use. Temp range: -40F or higher.

Relative performance in flashlights (taken from http://www.light-reviews.com/aa_shootout/ ):

http://www.light-reviews.com/aa_shootout/runtime_aa_080406.gif


<table class="sortable" id="reviews" width="100%" align="center" border="0" cellpadding="2" cellspacing="0"><tbody><tr><td>Sanyo NiMH 2700mAh
http://www.light-reviews.com/aa_shootout/sanyo_nimh_2700.jpg</td> <td valign="top" align="right">02:00</td> <td valign="top" align="right">2010</td> <td valign="top" align="right">30g
1.06oz</td></tr></tbody></table>
High capacity NiMH. When new they are very good batteries, but they wear out quickly with cycles and do not hold a charge over time well. Not the best value overall, but when you *need* lithium like performance at a lower cost, it is a good avenue.

Cost around $2.50-$3 on internet vendors

<table class="sortable" id="reviews" width="100%" align="center" border="0" cellpadding="2" cellspacing="0"><tbody><tr><td>Sanyo Eneloop 2000mAh
http://www.light-reviews.com/aa_shootout/sanyo_eneloop.jpg</td> <td valign="top" align="right">01:35</td> <td valign="top" align="right">1920</td> <td valign="top" align="right">26.3g
0.93oz</td></tr></tbody></table>
Low Self Discharge NiMH. This is the best value in convenient portable power. Long self life, good charge retention, long cycle life, good capacity, and improved cold weather performance over regular NiMH. There are several brands of LSD cells, but eleloop is the best brand that is widely recognized to have the best feature set.

Because of the exelent charge retention of eneloops, it is no longer necessary to store one time use cells for emergencies and their use can probably be deprecated completely.

Cost around $2.5-$3 on internet vendors. Also available at Costco.

<table class="sortable" id="reviews" width="100%" align="center" border="0" cellpadding="2" cellspacing="0"><tbody><tr><td>Eveready Super Heavy Duty
http://www.light-reviews.com/aa_shootout/eveready_shd.jpg</td> <td valign="top" align="right">00:15</td> <td valign="top" align="right">1600</td> <td valign="top" align="right">18.0g
0.63oz</td></tr></tbody></table>
Super Heavy Duty. Very poor performance, one time use. Not recommended for storage or use. Comes with cheap devices to shave pennies off production over including an alkaline. I would use 'em up and throw them away.

<table class="sortable" id="reviews" width="100%" align="center" border="0" cellpadding="2" cellspacing="0"><tbody><tr><td>GP Ultra Alkaline
http://www.light-reviews.com/aa_shootout/gp_ultra.jpg</td> <td valign="top" align="right">01:06</td> <td valign="top" align="right">1970</td> <td valign="top" align="right">22.8g
0.80oz</td> </tr> <tr> <td>Panasonic Alkaline
http://www.light-reviews.com/aa_shootout/panasonic_alkaline.jpg</td> <td valign="top" align="right">00:49</td> <td valign="top" align="right">2140</td> <td valign="top" align="right">23.1g
0.81oz</td></tr></tbody></table><table class="sortable" id="reviews" width="100%" align="center" border="0" cellpadding="2" cellspacing="0"><tbody><tr><td>Duracell Alkaline
http://www.light-reviews.com/aa_shootout/duracell_alkaline.jpg</td> <td valign="top" align="right">00:57</td> <td valign="top" align="right">1910</td> <td valign="top" align="right">23.9g
0.84oz</td> </tr> <tr> <td>Energizer Alkaline
http://www.light-reviews.com/aa_shootout/energizer_alkaline.jpg</td> <td valign="top" align="right">00:43</td> <td valign="top" align="right">1960</td> <td valign="top" align="right">23.5g
0.83oz</td> </tr> <tr> <td>Energizer e? Alkaline
http://www.light-reviews.com/aa_shootout/energizer_e2_alkaline.jpg</td> <td valign="top" align="right">01:19</td> <td valign="top" align="right">2040</td> <td valign="top" align="right">23.4g
0.82oz</td></tr></tbody></table>
Alkalines perform more respectably than Heavy Duty, but still only one time use. There is a wide margine of performance between brands and types. The best value is the Kirkland AA battery from Costco, which are rebadged duracells and sell for approximately $0.22 ea last I checked. Poor cold weather performance can effect winter use, but in a pinch this can be mitigated by putting the device in your pocket or otherwise warming up cells.

The advantage of Alkalines are the long shelf life, and good charge retention over time. Until you install them in a high drain device, once used slightly in this manner it's like opening a can of food. It will go bad soon if you use it or not. For most uses this is not a problem. This is a good short emergency backup for a low cost.

<table class="sortable" id="reviews" width="100%" align="center" border="0" cellpadding="2" cellspacing="0"><tbody><tr><td>Energizer e? Lithium
http://www.light-reviews.com/aa_shootout/energizer_e2_lithium.jpg</td> <td valign="top" align="right">02:26</td> <td valign="top" align="right">2200</td> <td valign="top" align="right">14.6g
0.51oz</td></tr></tbody></table>
Lithium is a high performance one time use cell. It has the longest shelf life, the best cold weather performance of all cells. It also has a price to match. The best place to puchase is at Sam's Club, the price will run about $20 for 12 cells or $1.67 ea. Energizer recently released a lower tier Lithium. The "Ultimate" has the blue label, the "Advanced" has the yellow label. The Advanced is generally the better deal, you get about 10% less power for about 30% less cost, while retaining all the advantages of the Lithium chemistry. Sam's is probably the best place to buy, I believe they are $14 for 12 or $1.17 ea.

This is a good short term emergency backup that performs well in extreme conditions.


I recommend Eneloops for general regular use and an emergency use battery. If you do not have a means of charging cells in a grid down senario, some one-use cells are advisable to extend your usable power beyond your eneloop supply's capacity without the expense of buying more eneloops. Some few Lithiums are in order if you expect extreme cold or can afford the better primary/one time use cells.

BackBlast
04-12-2009, 09:47 AM
Storage of batteries is like food storage. Store in a cool, dry place. Heat will diminish the charge retention and viability of cells. Lithiums do best over long periods exposed to heat. The refrigerator can work, it doesn't hurt them unless they get wet through condensation. I don't recommend it because of this potential problem.

ghostcat
04-12-2009, 10:49 AM
Great information backblast!!!! Thank you for posting it!!!!

ghostcat
04-12-2009, 11:09 AM
Looking for further information on the eneloop battery I came across this excellent review on amazon.


5.0 out of 5 stars Some new facts about LSD cells you should know..., <nobr>January 6, 2007</nobr>
<table border="0" cellpadding="0" cellspacing="0"><tbody><tr><td valign="top">By </td><td>NLee the Engineer (http://www.amazon.com/gp/pdp/profile/AOEAD7DPLZE53) (Nashua, NH) - See all my reviews (http://www.amazon.com/gp/cdp/member-reviews/AOEAD7DPLZE53?ie=UTF8&sort%5Fby=MostRecentReview)
(TOP 50 REVIEWER) (http://www.amazon.com/gp/help/customer/display.html?ie=UTF8&nodeId=14279681&pop-up=1#TR) </td></tr></tbody></table>
[Updated Oct 24, 2008]
My original review on the Sanyo eneloop NiMH cells was written nearly two years ago. Since then, I have learned a lot more about the characteristics about eneloop and other low-self-discharge cells. So it is time to clear up some inaccurate information I wrote about eneloop's self-discharge rate.

1. I was told that the Sanyo eneloop cells were not 100% fully charged when they leave factory. This makes sense because new cells are fast-charged in the factory to save time. In order to avoid problem with heat and gas built-up, they cannot be charged to 100%. I have tested some eneloop cells that were manufactured 20 months ago, and they still maintained about 70% charge. On the other hand, cells manufactured 6 months ago contain about 75% charge. This confirmed that the discharge rate is much lower than I previously estimated.

2. The self-discharge rate of eneloop (and other LSD cells) is not linear! My own testing showed that a fully charged eneloop may lose 10% of its initial charge during the first month of storage, but in the second months it may lose just 2-3%. The rate becomes even slower after three months. In fact, my 5-month self-discharge test using various brands of LSD cells gave nearly identical results as my previous 3-month test.

3. When an eneloop cell is freshly charged, its capacity actually measures at about 5% higher than its rated capacity (2100mAh vs. 2000mAh). In my previous tests, I used measured capacity as base to calculate the percentage loss. This results in apparently higher percentage loss. Had I used the rated capacity as base value, the self-discharge rate would be about 5% lower.

Based on the above revelation, I believe Sanyo's claim about eneloop (maintain 85% charge after one year, 80% after two year) to be accurate. Therefore the title of my previous review ("The News of LSD Has Been Slightly Exaggerated") has to be replaced.

Over the past two years, I have tested several different brands of LSD cells available from Amazon.com, including Rayovac Hybrid (http://www.amazon.com/gp/product/B000LPTDQQ), Kodak Pre-Charged (http://www.amazon.com/gp/product/B000WMK344), and Duracell Pre Charged (http://www.amazon.com/gp/product/B000XSA60I). They have all performed very well - practically no difference from the Sanyo eneloop. So the bottom line is: just pick which ever brand of LSD cell is on sale, and you can't go wrong.

The reason I posted this is he lists other brands that are available which he rates as highly, thus diversifying our choices which is a good thing!!

BackBlast
04-12-2009, 12:17 PM
Over a long term emergency when it is unreasonable to get buy with once-charged eneloops and single use primary cells, you must recharge your batteries.

On the low end, you can purchase this.

http://discoverpower.com/shop/images/products/productimg_md/BatChrg.jpg

http://discoverpower.com/shop/item.asp?cID=32&PID=159

It is a one unit solution for off grid recharging. It's a nice small package, but it is very slow at recharging. The recharge won't be as healthy for your long term battery longevity as a more controlled careful charge :mad5:. But in a short term emergency that's probably a lesser concern.

The next option for higher volume and better charging is a 12v system/charger. Which is most any charger that comes with a vehicle adapter, and a power source be it your vehicle, or solar, or other off grid power generation system.

A vehicle system is convenient, because you likely have a tank of gasoline, and using a tank to just charge batteries will last you months and months to possibly a year or more. You can use it to charge your cells all you need when you need your cells (without starting your car), and once a week you'll need to run your car for 20 minutes or so to fill the car battery back up. This can be made more precise if you can monitor your car's battery voltage and minimize your car's run time/gasoline and insure the voltage returns to the right level.

A solar power option is to buy a small panel, 10-15 watts, and plug your 12v charger directly into the panel. No battery is required, but you can only charge while there is sun. :l0 (57):

Now to the native 12v chargers..

Duracell 15 minute charger
http://www.emtcompany.com/prodimages7701/cef15nc.jpg

Can be purchased from here http://www.emtcompany.com/products/rechargeable-batteries/cef15nc-duracell-15-minutes-aa-rechargeable-battery-charger.htm ($20 with free shipping is a steal for this charger)

This charger requires lots of power, so you probably can't run it straight off a small solar panel (at least if you want to populate all 4 slots), but it is oriented more for convenient quick charging, this is likely to work well in a vehicle operation.

15 minute chargers are a little harder on cells than the best charging systems (10 Amps FTW! :d0 (24):), but they are quite sophisticated to be able to safely and reliably charge at those rates and I would say they are generally better than the dumb chargers, or even lower end smart chargers. They will not charge marginal cells.

Maha C9000

http://ecx.images-amazon.com/images/I/41MO8sKNVRL._SL500_AA280_.jpg

This is a good smart charger that will give you some information about your cells (battery nerds like me like info...). This product gives you a lot of care options for rechargeable cells. Cycling, breaking in, discharging, and charging options to help you get the most performance out of your cells. It can also help you match cells for use together and weed out poorer cells early. It runs off 12v, but does not come with a vehicle adapter or other 12v plug - which would need to be created for easier off grid use. This is a good option to get the most out of your batteries. :toetap05:

Available at Thomas Distributing http://www.thomas-distributing.com/maha-mh-c9000-battery-charger.php for $50.

Another route that's possible, and you should be aware of, though not ideal. Is the ability to run any charger off a 12v system through an inverter and it's own power adapter. The inefficiencies eat your power faster than the direct 12v chargers, but it does work. :patriot:

BackBlast
04-12-2009, 12:25 PM
Over the past two years, I have tested several different brands of LSD cells available from Amazon.com, including Rayovac Hybrid (http://www.amazon.com/gp/product/B000LPTDQQ), Kodak Pre-Charged (http://www.amazon.com/gp/product/B000WMK344), and Duracell Pre Charged (http://www.amazon.com/gp/product/B000XSA60I). They have all performed very well - practically no difference from the Sanyo eneloop. So the bottom line is: just pick which ever brand of LSD cell is on sale, and you can't go wrong.The reason I posted this is he lists other brands that are available which he rates as highly, thus diversifying our choices which is a good thing!!

Those are other brands. The advertising verbiage for these styles of cells is "Low Self Discharge" and "Pre-Charged" and similar. Most battery brands have a line. I still recommend the Eneloops over the other brands, generally, because there is a fairly insignificant price difference most of the time (~$2.5/cell). Eneloops are made in Japan where most all the other brands (Except Imedion, that I'm aware of, Imedion -> Taiwan) are Chinese. The Chinese cells usually have slightly higher capacity on the onset, but worse performance in general.

If you look at the original graph. It had another LSD cell:

<table class="sortable" id="reviews" width="100%" align="center" border="0" cellpadding="2" cellspacing="0"><tbody><tr><td>Titanium Power Enduro 2100mAh
http://www.light-reviews.com/aa_shootout/titanium_enduro.jpg</td> <td valign="top" align="right">01:01</td> <td valign="top" align="right">1820</td> <td valign="top" align="right">27.4g
0.96oz</td></tr></tbody></table>
It didn't perform as well, and it generally does not hold up as well. I have Enduros and Hybrids and have hammered them all. The Eneloops hold up much better in the long haul. Unless you can find significant discounts for the Chinese cells, I'd take the Eneloops.

The main feature which sets the eneloops apart is it's lower internal resistance. Most cell failure is with high internal resistance buildup. Starting lower seems to help the longevity and general performance of the cells.

Imedions have an interesting property, and that is a generally higher voltage and voltage retention. More so than most LSD cells have - which is generally higher than regular NiMH. IMHO, lower internal resistance > better voltage retention, but it has it's place in better performance in more voltage sensitive devices.

Brandon

Aldon
04-12-2009, 02:49 PM
I am all for buying Japanese products rather than Chinese.

DMGNUT
04-12-2009, 07:54 PM
Backblast, this is a great thread. Way cool of you to take the time to put it all together. Thanks man.

BackBlast
05-02-2009, 08:36 AM
Found a cheap source of lithium cells. These weren't stored under ideal conditions for some period of time, but they are pre-sorted and you should get some good cells.

$0.5 ea for sorted loose cells.

http://www.cpfmarketplace.com/mp/showthread.php?t=190869

I found a deal like this a few years ago and have been pleased with the value.

BackBlast
05-25-2009, 09:52 AM
Last time I was there, Costco had eneloops on sale (Manf. discount). 8 AA, 2 AAA, Charger, and sleve adapters for $20. A pretty good deal.

BackBlast
10-06-2009, 06:30 PM
New press release from Sanyo is stating that materials improvement is resulting in even better Eneloop longevity. Summary: advertised cycle life is changing from 1000 -> 1500.

http://www.cdrinfo.com/Sections/News/Details.aspx?NewsId=26069

The best is getting better. Now, when will I be able to find these....

Brandon

BackBlast
11-14-2009, 10:41 PM
Duraloops (rebadged eneloop cells as duracell pre-charged rechargeables) are on sale at Costco. 18.50 for 10 (8xAA, 2xAAA) with a $5 off coupon for 1.35$/cell before tax. This is the best price I've ever seen for these cells.

There is a catch though, some of the batteries badged as pre-charged duracells are really china made... You can find either or at your local Costco (usually all one or the other).

http://g-ecx.images-amazon.com/images/G/01/ciu/0d/01/2e1be03ae7a00c564ee6e110.L.jpg

If you notice, the two duracells on the top of this image. The black ring is the china cell, the white is the Japanese. This can also be verified on the cell label, the white will say "Made in Japan" and the black will say "Made in China", ignore the wrapper which always says "Made in Japan".

I've looked around at a few of the Salt Lake Costcos, at present, 106th south has the duraloops, 54th S, 17th S, and WVC stores all have the China made cells.

This is a great deal if you have a membership.

BackBlast
06-15-2010, 11:24 AM
...Lithium is a high performance one time use cell. It has the longest shelf life, the best cold weather performance of all cells. It also has a price to match. The best place to puchase is at Sam's Club, the price will run about $20 for 12 cells or $1.67 ea. Energizer recently released a lower tier Lithium. The "Ultimate" has the blue label, the "Advanced" has the yellow label. The Advanced is generally the better deal, you get about 10% less power for about 30% less cost, while retaining all the advantages of the Lithium chemistry. Sam's is probably the best place to buy, I believe they are $14 for 12 or $1.17 ea.

** Lithium AA Sale Alert **

Lowes has the lower tier Lithium "Advanced" series on clearance for $0.50/cell. Which is a very good deal, less than half the best prices you can typically find. You will find them in the battery display at the front of the store, the clearance item is the silver/yellow Lithium advanced in a package of 2. Regular price is 3.79 or so. My local Lowes had the 0.99$ marked, some apparently don't but should ring up 0.99$ anyway.

If you can't find any, you may ask to see if they have any stock left somewhere so you can relieve them of their undesirable SKU.

If you have extra money and would like to store some premium cells, this is a good opportunity. I would not purchase these over a reasonable supply of LSD cells first, but they work well as a complement to them.

BackBlast
07-11-2010, 08:23 PM
I've been running some tests on some of my older cells. I would like to report that I have a number of LSD cells that are over 4 years old now. Almost all are still functional and still report good power levels. I think I've only thrown out one or two out of dozens in that time period. I even had one that was severely abused due to a boy putting it into a device wrong that shorted the cell and drained it to zero (melting the devices in the process). It still takes a charge though I can tell it has suffered a little. It is still functional if a little worse for the wear...

The biggest losses come from entering devices that are seldom used and basically getting lost.

There is a recommended cycle rate for rechargeables (they do not, historically, last as long as primary cells), I believe on the order of 2-3 years. I think with LSD cells 4 or 5 is probably okay, it's probably wiser to purchase 20% of your intended stock roughly yearly so you always have some fresher and some older ones.

BackBlast
07-26-2010, 02:02 PM
My most recommended cell just came up with an improved line. Sanyo makes these claims about the improved new Eneloop line

* Improved cycle life, 1000 -> 1500.
* Improved charge retention (85% after one year to 75% after 3 years).
* Improved low temperature performance, from -10C to -20C

Basically, Eneloop's biggest strengths and reasons to use them just got better. And by the claims, significantly better. I won't know how they compare exactly until I've seen a few independent reviews that will probably surface months from now. But based on reputation, I would probably buy these new cells if I were in the market to buy rechargeables. They are available at Costco for $26 (or soon will be if you can't find them quite yet) and Amazon (http://www.amazon.com/gp/product/B003VLAEPQ?ie=UTF8&tag=amazona384-20&linkCode=as2&camp=1789&creative=9325&creativeASIN=B003VLAEPQ) for $37 (I would suggest purchasing them from Costco if you can manage it).

BackBlast
10-14-2011, 09:49 PM
I guess it won't hurt to bump this thread. From what I've learned, the 2nd gen eneloops are IDENTICAL to the originals. It seems that they were so good they decided to give them a marketing upgrade and new colors. They remain the best cells on the market.

BackBlast
03-22-2012, 07:21 PM
My first youtube video, this is probably the best thread for it.

AA battery storage and organization.
http://www.youtube.com/watch?v=x_UyxW7avGg (http://www.youtube.com/watch?feature=player_embedded&v=x_UyxW7avGg)

CurtisG
03-23-2012, 03:11 PM
Thanks, i will adopt the FIFO system. I went to rechargeable AAs a few years ago since the kids were going through them like candy. Took awhile to train the kids to use the charger...not to mention checking to make sure they didnt end up in the trash.
Btw, are you saying that a 500S&W is like getting shot with a AA battery going 2000 feet per second? :d0 (69):

BackBlast
03-23-2012, 07:43 PM
I forgot to mention in the video that another reason for the FIFO is that you don't end up with any "stale" batteries hanging around that have been off the charger a long time and lost it's charge. Or at least, if you do, you have a pretty high confidence that you can just throw it away. This aspect was more important with pre-LSD type cells, but it's still useful today.


Thanks, i will adopt the FIFO system. I went to rechargeable AAs a few years ago since the kids were going through them like candy. Took awhile to train the kids to use the charger...not to mention checking to make sure they didnt end up in the trash.

I always make sure to give the kids my oldest and least valued cells. :-)


Btw, are you saying that a 500S&W is like getting shot with a AA battery going 2000 feet per second? :d0 (69):Not quite, ammo boxes need to accommodate the case as well as the bullet. The maximum length of 500 S&W is sufficient to accommodate a AA cell - the actual bullet is much smaller. For some reason they make ammo boxes much better than I've ever found in battery boxes :-)

But I would rather not get shot with either http://www.ldsglo.com/forum/images/smilies/d0%20%2869%29.gif

CurtisG
11-23-2012, 12:45 AM
Ordered a pack of Eneloop 1500's that has 12 AA, 4AAA,C&D spacers and charger in a handy case.
Going to try to switch to all rechargables since the kids have all moved out and the batteries will be safe from accidental disposal.
Still need to find a solar/hand crank recharge method.....with a USB connection for the cell phones. (off grid charging of cell phones is a lesson from Sandy)

BackBlast
11-23-2012, 09:55 AM
Still need to find a solar/hand crank recharge method.....with a USB connection for the cell phones. (off grid charging of cell phones is a lesson from Sandy)

The integrated solutions for solar+charger are generally rather poor. My preference would be a panel, a 12v battery, and a 12v charger to give you more flexibility and better control. You can always use your car battery as the 12v battery with no investment. Just try to keep it topped off with your panel.

Hand cranks will be disappointingly fragile and unreliable. You may not realize just how much work you would need to do to charge a cell.

thomasusa
11-23-2012, 11:21 AM
I really like the new Eneloop LSD (Low self discharge) batteries.
For a prepper, this is the best of both worlds - having you cake and eating it too.
Like NiCad and NiMh they are rechargeable - they claim 1500 times.
But almost like alkaline, they can store on the shelf without going dead as fast as rechargeable.
(After 2 years the they still claim 85% power remaining.)

Beware: there are counterfeit Eneloops on the market.

I noticed that Costco has Eneloop AA in 10 packs for $20.
Slightly better than the 8 packs for $20 I found earlier.
I tested the Costco version and they seemed to be within specifications.
I have not waited the 2 years yet to test self life.

I did not like the dumb charger offered for the Eneloop.
I went with the Maha C9000 instead (and I think I'll buy a spare.)

http://www.thomasdistributing.com/HOLIDAY-SPECIALMaha-C9000-AAAAA-Battery-Charger-with-a-FREE-Four-Pack-of-Maha-Imedion-AA-2400mAh-Batteries_p_3151.html?frontpage=1


The integrated solutions for solar+charger are generally rather poor. My preference would be a panel, a 12v battery, and a 12v charger to give you more flexibility and better control. You can always use your car battery as the 12v battery with no investment. Just try to keep it topped off with your panel.

Hand cranks will be disappointingly fragile and unreliable. You may not realize just how much work you would need to do to charge a cell.

I agree.
Plus the off-the-shelf solar changers have such a small solar panel that all day winter charging seems to never fully charge.



With LED flashlights, a solar panel and the lighter plug for the charger, I think I have renewable lighting covered.

CurtisG
11-23-2012, 02:20 PM
Hand cranks will be disappointingly fragile and unreliable. You may not realize just how much work you would need to do to charge a cell.
True, i have read many bad reviews about hand cranks. I do have 2 solar panels from a gate opener that doesnt work anymore, i could use those to charge a 12volt battery.

BackBlast
11-28-2012, 11:17 AM
Eneloops are on coupon @ Costco... I believe till December 16th or until the stock is all gone. $20->$16 for the 10xAA or 12xAAA packs. They seem to do this in December every year, and it's probably the best deal you'll find...