Tenergy AA Rechargeable Batteries 2000mAh Pre-Charged Low Self Discharge for Remote Controllers, Toys, Flashlight, Mouses, 4 Pack

I've consistently been able to find these for ~$1/cell for AAAs and AAs for a smidge over $1.50 if bought in a 24 count. You can combine shipping somewhat on these items (like 6 cards of AA and AAA respectively), the savings add up. I've bought 84 AA cells and 48 AAA cells over this year in addition to the 24 AA and 8 AA Enerloops I got at the beginning of the year. Everytime I look, the Enerloops seem to cost more. The white label Amazon Basics seem like a good compromise, and they have sales now and then but it's never running when I'm buying. Of all my Tenergys, most are ~ 6 months old. Having 3 little kids with a LOT of battery-powered toys, most of the batteries have all seen a few dozen cycles now.I recently used my La Crosse charger to do a recovery on my oldest cells and found that, on initial discharge, the AAs still over 1850 mah per cell at a minimum (most still were around 2000) and of the weaker cells, they all recovered to >1950 mah.The only thing I can say negative about the cells are that their positive posts are rather short. While this doesn't affect their ability to be used 9 out of 10 times, it has caused me to hold the enerloops back for the odd item here and there that the tenergys cannot be used for. I recently had to buy another batch of both 24 AA and AAA cells due to breaking out off of the Christmas stuff and having 'battery anxiety', having pretty much no cells at the ready to be used. This will mean I'll have quite a few batteries charged at the ready, limiting their cycling. I feel pretty confident age, not cycling will render their capacity poor given enough years. I will rotate them through to keep cycling them along to try and make them go as long as possible.All in all, these cells have been the best bang for the buck between enerloops and tenergy. While I've looked at other cells and nearly pulled the trigger on buying them, Tenergy's consistent performance for a price that seems unmatched by any other (reliable) have kept me buying them. At my current battery inventory, I will likely have enough cells to not purchase anymore until they begin the degrade. I may make updates to show long term degradation.Being a submarine electrician, batteries have always held my interest, though what we use in the fleet is limited to SRVLA and up until recently flooded lead acid. I've really enjoyed getting my hobby chargers and a slew of rechargeable cells this past year. I had dabbled in nimh cells ~6-8 years ago that were not LSD and found I couldn't readily depend on them for low drain devices and they seemed to fail rather often. At this point, out of the ~150 cells I've purchased, I've yet to experience a bad cell and have all but eliminated the alkalines from my house, other than a few stragglers in remotes that'll get changed out with Tenergys when they finally bite the dust..If you've been looking at taking the plunge, ESPECIALLY if you're replacing battery's on a monthly basis (and it'll be more often than that if you've got kids), I highly encourage you to make an investment that will save you a pile of money in the long run and has the convenience of always having a supply of batteries at the ready. Granted, I spent a pretty penny this year between the cells, 2 good chargers, a Nitecore that does double duty to charge all my lipo batteries and my snazzy La Crosse, but I don't plan on spending anything on batteries for the foreseeable future. I've contemplated Tenergy rechargable Cs and Ds, but I use them rarely (Cs almost never) and most of the time I do, I have D cell adapters to use my AAs in, letting me get by on much lower capacity, but already purchased cell that can be recharged.***Update June 2015***All but 1 of my Tenergy AAs continue to work well. One appeared to develop somewhat of an internal short and required excessive charging to reach a charged state and had a high rate of self discharge. This is 1 failure our of ~100 cells over about 1 year. Comparatively, the dozen or so Enerloops have had no problems and I use on my highest drain devices as they seem to have slightly more capacity (tend to take ~ 2.3-2.5 a-h over the 1.9-2.3 the Tenergys do). While I have not done a refresh yet on any Enerloops, I have done a single refresh on ~1/3-1/2 of my Tenergys and have seen them appear to regain any/all lost capacity (except the one dud). This is done whenever I notice any that are fully discharged receive <2000mah on a charge. Again, despite the fact these do seem to not be quite as good as Enerloops, you're getting far more cells for the money at ~90% the capacity. The money saved can go a long way to purchasing extra cells which limit the cycles on existing cells, lets to power more devices and allows you to keep more charged cells on hand when it is time to swap batteries out.***Update July 2016*** No other failures to report after another year between my AAs and AAAs. The one last year must have been a fluke. The cells are actually outlasting a Lacrosse 700 Mah charger I got for the main purpose of using the refresh feature, as one of it's slots doesn't charge at all and it's LCD panel is failing with it being unreadable for a couple cells. My kids are 5.5, 4 and 1.5. There was a time most all my cells were in use due to so many battery powered toys in the house. Now I have probably 30 of my 100-ish on standby in an old cigar box and 4 of my 50-ish AAAs on the box (little pirate ship for the boy uses lots of AAAs. I am constantly still rotating them through and they all seem to perform well, with the exception of 1 AAA. Pulling 3 from a LED toy, with 2 cells still >1.2 and one sub 1v. Charger only put in ~530 Mah. Refreshed it up to ~750 Mah, though that's a little light.I'll likely get another charger as my go-to is a i4 Intellecharger from Nitecore that'll charge my 18650s I use for my flashlights as well (great charger, BTW.). I used to do a 4 cell refresh ever 3-6 months for a catch of cells but I haven't been able to do that for nearly a year. I still will do a single cell now and then if it seems to have a substantially lower voltage after use, but they've been coming back to near it's ratings.I think I bought another 6 pack (24 cells) of AAs nearly a year ago, but most of them are 2 years+, and all of my AAA are over a year old... many pushing 2 years and going strong.As a note, I've had a few D-cell items when the youngest was a baby and used AA's with the AA to D cell adapters almost exclusively. While the run time was certainly diminished due to the lower capacity (I was swapping cells in a crib mobile about every week), I never really had to buy D cells. Ever. Pretty convenient.***Update November 2017***I did another round of refreshes and noted no real loss in capacity. I'm still using many battery powered toys with my kids now 7, 5 and 3. Of all my cells, I probably have 30 AAs and 12 AAAs charged and ready to go at anytime, with the rest in use. I cycle them through to ensure they all get used. I haven't bought a single alkaline other than some 9vs for smoke detectors in something like 3 years and have a pile of cells at the ready.Living in SE GA, when a hurricane threatened, I put fully charged batteries in all my battery powered items and charged everything that had been in use, ensuring everything in the home was charged. That way, I could scavenge batteries out of things I wasn't using if needed, and they'd be fully charged.I don't put much thought or care in my batteries. I have them, they're ready to go. They've paid for themselves several times over and continue to do so. Even if I have a handful of cells fail a year (and I've only had 1 failure in 3 years of the 100+ cells I have), I'm still a few years away from needing anymore. Highly recommended.***Update May 2018***I did another round of refreshes this past month. I noted 6 cells out of ~100 having exhibited capacity loss to where they are under 1800 mah. All were still ~1500 mah. I've written on them what their capacity was and earmarked them for low drain devices (ie remotes). Otherwise, I'm still going pretty strong. No outright failures. I haven't brought AA/AAA batteries in a few years now... save some 9v for my smoke detectors and a 2 sets of 4 Tenergy C Cells as I have a few devices that use them and it made sense to have dedicated cells for. AA to D conversions still work for what little D cell needs I have.***Update November 2018***Well, I had 1 AAA fail by leaking very slightly and tossed it... though nowhere near as bad as an alkaline can be. So now that's 2 cells down for the count after something like 4 years with no cell being younger than 2-3 years old. Not too shabby. I just went through and cycled all the batteries through the chargers getting ready for all the Christmas ornaments and little LED light strings I drape on my small apple tree that's in the middle of the yard, and wrapped around my mailbox. I expect I may finally start getting some failures in the coming year, but these cells have paid for themselves many times over both in cost and convenience.Now that some years have passed, I will say that the 24 or so Enerloops I purchased ~4 years ago (I can't remember it's been so long... heck, I don't think I've bought any more AAA or AA in 2-3 years... and that was to bolster my number of Tenergys) have all consistently retained full capacity with no failures and have consistently less internal resistance when checked against a random Tenergy cell. The majority of the Tenergy cells are still >90% after most have had many dozens of cycles... with the few aforementioned at ~75%. Those have been semi-retired to flameless candles and remotes. But... again, after 4 years I'd have to say, no, they aren't as good as Enerloops regarding maintaining capacity over time. That still represents about 90% of all cells still at > 90% capacity with a ~2% failure rate given my collection of somewhere between 100-150 cells. For their price point, I still think they represent an outstanding value. Considering the ability to spread more, albeit slightly lower capacity cells around vs the Enerloops for the same money invested based on the lower per cell cost, the Tenergys are still the way to go in that regard. I hold my 5 star review but after nearly a half decade, the Enerloops are showing to be a superior cell... and are priced higher accordingly.Update: 11/30/19: 5 years! No more failures over the last year. I did a refresh on all the cells mid-year as we had a few hurricanes make some close passes and noted most the cells were still holding 90%+ capacity with the few that were around 75% still hanging. I just spent the evening putting up Christmas stuff and emptied my “box of batteries” out into all the random ornaments and Christmas noise-making fun things. They’re still hanging in there and it’s been a few years now since I have bought a single AAA, AA, C or D cell. Between having all but the Ds, and adapters to fulfill that role... I’d be hard pressed to say how much I’ve saved over the years, but it would be several times the amount I ever spent on these. Not to mention, I’m never, ever without a battery. You never run out, you just toss the dead’s on the charger and pull a set of charger ones out of the box of batteries.Update 12/11/20: I had one more of the AAA fail out of the ~150 or so AA and AAA in the last year. High resistance made its voltage rapidly spike up... and got noticeably warmed in the charger... so it got chucked. I’ll be doing another round of refreshing at the end of Christmas... but my battery box (once again!) was nearly emptied out to put batteries in a couple dozen items... from ornaments on the tree to noise making plushies we spread around the house for the kids to play with. At some point I think I’ll start discarding old cells that are far below 75%... certainly below 50% and replace as needed to cover my needs during the holidays. It just hasn’t happened yet. It’s been 6 years now though and I still haven’t bought an Alkaline battery for my entire 6 year old son’s lifetime. I’ll keep them going as long as they’ll keep working for me. I wouldn’t think they’d hang for an entire decade... but we shall see...Update 10/31/21: About 7 years. I think that’s it. Pretty much all the cells remaining look like their capacity is now about 1400-1600 at the most with 1/4-1/3 south of that. More importantly, internal resistance has climbed to where my Opus BT-C2000 will no longer charge them at a 1000 mah. Most will only charge at 400-600 mah. Here in the last year, they just kind of aged like milk… and it’s kind of been most of them. The same internal resistance slowing charging rates make them have a Vdroop making them unsuitable for high drain devices.So what to do? I see I can get 60 AAs for $50 for a subscribe and save then cancel it and replenish my inventory. That’s well under $1/cell. Then? I think I’ll clearly mark the old cells and have them semi-retired to low discharge devices (i.e. flameless candles). I’ve had to discard 2 or 3 from no longer accepting a charge as well this past year, more than any other year.So… this may well be my last update. 5 very good years with only a failure or two then it’s been a gradually worsening trend from years 5 through 7 and at 7 years. Attempts at running them through recovery cycles is no longer recovering much, if any capacity. Stick a fork in them… they’re pretty much done.Update 12/4/22: Well.. I did get 60 replacement Tenergys for about $50 and 24 AAAs for under $20 around a year ago. I kept 1/2 of the best of the old cells for low drain devices and have the new cells for everything else. I expect this $70 investment will cover me for another 5 or so years from now at least. By then, my kids will be nearly grown.Not as a knock for the Tenergys, but the Enerloops I bought 8 years ago are still hanging in there, but I could buy 3 Tenergys (can buy AAs in a 60 quantity for under $1/each for the cost of 1 Enerloop (their best price is juuust under $3/each).If money is no object: get Enerloops. I pondered doing just that, but wasn’t willing to spend 3x the money for 1/4-1/2 of them to sit unused until Christmas. If you’re like me and have kids and times (like Christmas) where you literally need 100 batteries or more on hand to run piles of things… Tenergys are more bang for the buck. I think most of us won’t ever test the couple-thousand cycle limit of any of these cells. I’d be surprised if any of mine exceeded 100 cycles, and 1/4-1/2 my cycles are through refresh cycles on my charger. Age will get them first… 5-10 years seems like as long as you can hope for. If you look on the web there’s a little bit of data on 10-12 year old Enerloops and age gets them too eventually to where they’re only for low drain devices. They just fail a little less and hold up better along the way. Cost/performance for my usage style just isn’t there for me.

A few years ago, I bought some nice chargers (Powerex) and a whole bunch of rechargeable batteries. I wanted low self discharge so that I wouldn't have to keep checking if they were charged. I use them as emergency batteries as well, in lanterns and flashlights, so they need to be charged if the power cuts out (and if your power company is CL&P you can count on that being for weeks at a time on a regular basis).Anyways, I've found them to be excellent and use them in just about everything. I only use alkaline for smoke detectors, and that's partly because I don't have a 9V charger, and partly because alkaline does have the slowest self discharge (but are not rechargeable). You could probably use tenergy centura 9v in smoke detectors too.I've gone over a year w/o charging a battery and it functions like it was just charged. I'm sure there is a small amount of charge loss in a year, but I don't notice it. I would recommend the centuras as your main rechargeable go-to battery - I've been pleased I made the choice. Versus the eneloop, they are much cheaper and come in more sizes (I use D batteries in flashlights and lanterns, and in some other items - eneloops don't offer these). These will work for years in a remote control, wireless keyboard/mouse, or other low drain application.If you do go all rechargeable as I have, I would recommend going with a top notch charger. I strongly recommend the Maha/Powerex smart chargers, they have a very advanced charging logic built in, and I got mine on Amazon. I think that most people who have problems with low self discharge NiMH batteries do so because they buy lousy, cheap chargers that trickle charge or have poor mechanisms of detecting when the battery is full, and this is very bad for rechargebles, especially NiMH - the voltage drop that occurs briefly as the battery is full is less obvious than with NiCd. I think the Maha/Powerex Imedion line are probably a bit greater in charge capacity, but the price is far too high, so I use the tenergy batteries for much less money.Lastly, NiMH are not very toxic at all, can be disposed of (when they finally become useless - I have yet to throw any out) in the trash. Much, much safer and more green than the NiCd batteries. They also hold much more charge than NiCd. Lithium aren't practical in general as a replacement battery for regular sizes like AA, AAA, C, D, etc. - and I don't think you can even get rechargebles.