I recommend only one inexpensive battery charger among hundreds of possibilities. It is the Panasonic Eneloop BQ-CC17 which can be had for $15 at Amazon in white or black, or as part of several possible bundles that include Eneloop batteries.
Update 3/12/17: A new post on this site compares this charger with two other budget chargers that have faster charging rates. The BQ-CC17 compares favorably. See Best of the Budget Chargers.
I bought a BQ-CC17 bundled with Eneloops two months ago. The rest of this post is my review of the included BQ-CC17 charger, as well as the criteria I use to eliminate other low cost chargers from consideration.
What Makes for a Good AA Battery Charger
When I first started writing about AA batteries and chargers a few years ago, there were several worthy, low cost chargers on the market. I recommended three of them. All have been discontinued.
I go into great detail about what makes for a truly outstanding battery charger in my La Crosse AA Battery Chargers post. La Crosse and several other outstanding charger models offer numerous features that go far beyond what I consider to be minimum requirements. But these premium models cost $35 or more. If you use lots of AA batteries and don’t mind the extra cost, then I suggest you pick one of the premium models described in this comprehensive post about batteries and chargers:
Best AA Batteries and Chargers: 2018 update
The criteria for buying a good battery charger boils down to the phrase, “smart charger.” This is a marketing phrase. It generally means that the charger has one or more features, the most important of which is that it contains circuitry to stop charging batteries when full. The quality of full battery detection varies depending on method, with the “negative Delta V” method generally considered the most reliable.
Many inexpensive chargers contain this one feature, and quite a few use the “negative Delta V” method. The problem is that very few contain a second “smart” feature that is also very important: individual charging channels for each charging bay.
Nearly all low cost models charge in pairs. A typical 4 charging bay model has two pairs of two. In each pair, if the charger stops charging when the first battery is fully charged, then the second battery will be only partially charged. Alternatively, if the charger stops charging when both batteries are full, then one battery has been overcharged, which shortens the life and effectiveness of the battery. In either case, an unsuspecting consumer will think that there is something wrong with their batteries, when the fault is using a paired bay charger. Also, paired chargers require that both batteries in each pair be either two AA or two AAA batteries, so another advantage of individual charging bays is being able to put in any mix of AA or AAA batteries in any order you want.
I did not need to test hundreds of chargers to identify this one good model. I just read through the descriptions and reviews for all the inexpensive models I could find on Amazon (U.S.). I found only one with both full battery detection and independent charging bays. It is therefore the only one I recommend. If anyone reading this knows of another low cost model with independent charging bays, please leave a comment.
Everyday Use of the Panasonic Eneloop BQ-CC17 Battery Charger
When reviewing products, I don’t like conducting numerous artificial tests over a period of a few days. I prefer using a product over a few weeks (or longer) as just a regular user. After two months of use, I have the following observations:
First, and most importantly, the BQ-CC17 lives up to its claims. Batteries are never hot to touch when charging occurs or is complete. Upon charge completion, all batteries are always full (I can tell by placing into my La Crosse charger). That’s exactly what I wanted to see—a confirmation that independent charging bays work independently.
Despite its small size, I have no trouble inserting or removing AA batteries. However, I found inserting smaller AAA batteries puzzling at first as I am used to laying them flat in other chargers. I couldn’t get that to work. The included instructions make clear that AAA batteries do not lie flat in the charger, but rather at a slight angle. After inserting AAA batteries a few times I got used to it.
The charger is small and light. It has no power cable, but rather a retractable plug, so it is more compact and convenient to travel with than premium chargers that are twice as large. It accepts 100-240V AC, so it can be used worldwide if an inexpensive adapter plug is purchased.
There are no options of any kind. You simply insert batteries, and see a solid green LED light come on for each battery bay that contains a partially charged battery. Each individual bay has its own LED light, a handy feature not available in most chargers. Once an individual battery is fully charged, the light for that bay turns off. The AA battery charging rate is 300mA, while the AAA battery charging rate is 150mA.
The included instructions say “LED charge indicator lights will begin blinking rapidly after plugging the device in to the AC outlet.” This does not happen on my BQ-CC17. However, I have seen a rapidly blinking light when a battery is failing to charge.
I did not understand what the blinking light meant at first. After much experimentation, I observed that the blinking light never occurred with low self-discharge batteries such as Eneloop. My testing included a couple older AA Eneloops with maximum capacity of only 1700mA. It only seems to occur on older, low quality, high-discharge batteries which could no longer charge to full capacity. It doesn’t matter whether the charge is full, partial, or empty—the LED blinks rapidly to indicate an error condition and refuses to charge these older batteries.
This could be viewed as a negative, in that this charger can’t charge older, low quality batteries. Or this could be viewed as a positive: the blinking light is a simple way to identify batteries that you want to throw out because of high internal resistance and low maximum capacity.
I never recommend high self-discharge batteries as they are far less convenient to use than low self-discharge batteries such as Eneloop. I’m guessing those who stick with high quality low self-discharge batteries will never notice rapidly blinking lights as a battery fails to charge. If you do see the blinking lights, you probably have a battery that is no longer worth keeping.
I consider the biggest drawback of La Crosse chargers to be their failure to charge over-discharged batteries because the voltage drops too low. The BQ-CC17 charges such batteries so is a useful complementary charger for those who already own a La Crosse model and occasionally see the “null” message.
The only thing not to like about the BQ-CC17 is the relatively slow rates of charging. A fully depleted AA battery will take over 7 hours to charge. The one and only change I would make to this model is to have the charging rates be 500 mA for AA batteries and 200 mA for AAA batteries. So far as I know, these rates are just as gentle on batteries as 300/150 rates (note though that rates higher than 500mA for AA and 200mA for AAA are known to decrease battery life). If you always have an extra set of fully charged batteries available, the slow charging rate won’t matter.
If charging more rapidly on occasion is important to you, consider purchasing one of several good premium chargers.
Concluding Remarks
It’s hard to understand why so many mediocre chargers exist. I suspect that it’s because of the low price. Most people won’t spend more than a minute or two on a $15 purchase, because it hardly seems worth the time.
Well, it turns out that taking the time to buy a decent charger will result in batteries lasting longer between charges, and therefore fewer battery changes. Taking 5-10 minutes to choose a good charger may end up saving a lot more than 5-10 minutes in the long run.
Thanks for this useful information!
WRT “The only thing not to like about the BQ-CC17 is the relatively slow rates of charging.” Apologies if this is a stupid question (I’m a total ignoramus in such matters): is the total energy outlay reduced if less time is spent charging? That feels right to me, on the grounds that it’s best to turn mobile phone chargers off at the power socket when they’re not in use (as they otherwise still draw, and waste, electricity) — but perhaps it’s as dumb as believing (as I know some do) that it uses less fuel to drive as fast as possible from A to B…
PS Typo alert:
“…the blinking light never
occuredoccurred with…”“…batteries which
hadcould no longer charge to full…”Hi Colin,
Thanks for catching the typos.
I don’t know the full answer to your question even after doing a little research today. So I’ll try to be careful with my answer to say what I do know and what I don’t.
A battery can be modeled as a power source along with a resister. All batteries have some internal resistance. Resistance varies depending on a number of factors (see http://en.wikipedia.org/wiki/Internal_resistance).
So here’s how I think about the answer to your question: The total energy outlay you ask about will consist of two components: The short run (you are charging brand new batteries) and the long run (what happens to energy efficiency over the life of the battery, depending on how you charge it).
In the short run, I’m not totally sure but I suspect if you “trickle charge” at very very slow rates then a significant portion of the energy will be wasted due to internal resistance. If you charge at a super fast rate you will waste energy due to generating heat. So my guess is that there is some happy medium. For AA batteries that may be somewhere around 300mA to 500mA as that seems to be what is generally recommended but I really don’t know as I haven’t seen any data or conducted any tests myself to figure out the optimal charging current.
What is more well know is the long run effects. If you charge at a very high rate (i.e. 1500 mA) you cause the battery to heat up and if you do this many times the internal resistance of the battery will gradually increase. When the internal resistance increases, the battery becomes much less efficient with high drain devices such as digital cameras. So, you may be able to use a brand new NiMH battery to take 200 or more pictures on a digital camera (mostly without flash), as the internal resistance is low. But that same battery will likely have a much higher internal resistance years later after many rapid recharges – and then it will only take a dozen or two pictures as the high current requirements of the camera combined with the internal resistance very rapidly drains the battery. Thus – in the long run, if you frequently treat your batteries in a way that increases the internal resistance (namely by rapid charging, though anything in general that causes the batteries to become very hot will hurt as well), then you’ll be making far less efficient use of energy.
Note that leaving your batteries in a charger for weeks at a time can also be damaging to batteries, increasing internal resistance – at least that is what many people claim. I haven’t tracked down the science of why this is.
Yet one last note – Delta V circuitry in smart chargers does not work reliably if the charging current is too low (i.e. 100mA for AA batteries). If it doesn’t cut off, the battery will over charge which is another way to damage batteries and increase internal resistance.
So – in a nutshell, you’ll optimize your energy use over the long term by buying high quality low self-discharge rechargeable NiMH batteries such as Eneloops, and taking very good care of them by charging at low-medium rates (300mA to 500mA for AA) and keeping them away from heat.
Panasonic now makes a BQ-CC16 charger, which should charge more quickly than the BQ-CC17.
Homer – I had considered including the BQ-CC16 but I chose not to. For one thing, it is not easily available in the U.S., which is where most FilterJoe readers are from. But I also examined all three chargers on Panasonic’s Eneloop Charger Page:
http://www.eneloop.eu/eneloop-products/chargers.html
Reading through the specs, I saw that only the BQ-CC17 used negative Delta V as the cutoff method to detect when batteries are full and stop charging. This is widely considered to be the most reliable method for AA battery charging cutoff control. It is a little surprising that the BQ-CC16 uses Peak Cut Control, which is generally not as reliable. Given the track record of reliability behind the Eneloop brand, I would guess that the BQ-CC16 was extensively tested with Eneloops and would be safe to use with Eneloop-branded batteries, as well as other batteries produced in the same factory in Japan (such as Amazon Basic low self-discharge batteries). But it is possible that the BQ-CC16 would not perform well with some other types of NiMH batteries, possibly undercharging, or, more dangerously, overcharging.
So I stick with my recommendation for now: BQ-CC17.
Ah, I was looking at the panasonic.net (global) page and didn’t see the eneloop (Europe) page. As you wrote in your review, speed matters less if you have spares.
Joe, I just looked at the Panasonic page you posted and on the BQ-CC16 specs it reads: “Charging control: Smart Charge1/-ΔV /Timer”.
So even though it isn’t mentioned in the descriptive text right under the header (which ends with a mere “The charging progress gets checked and ended for each single cell via Peak-Cut-Control.”), this charger should indeed make use of the Negative Delta method.
I have this same charger. Tonight I was charging 4 AAA eneloops. 3 charged fine the last one was blinking. First time I’ve seen a blink. These are relatively new, probably under a 100 charges. I reinserted it and it charged fine.
Thanks for this report. If you have access to a high end charger, it would be good to test the capacity of the battery that had the blinking light. Might be that battery’s capacity is unusually low.
Unfortunately, I don’t have any high end equipment. If it matters, the blinking did not start until well into the charging cycle. I stumbled onto your site while googling BQ-CC17 blinking. Thanks for the reply.
Joe, thanks for this great article.
I recently bought some Eneloops with the BQ-CC17 charger.
Curious about the charger, I tried charging some old NiMH batteries and saw the blinking light behavior you described. I measured the current those older batteries would deliver through a 0.1 ohm resistor and could correlate their current delivery – around 200 ~ 500 mA, with whether the charger light would blink. One battery from a camera rechargeable pair could drive 700 mA; it completed a charge cycle in the CC17. The other battery from that pack, which could drive ~ 350 mA, started to charge, but later gave the blinking light.
Those batteries were from my daughter’s camera; she complained they wouldn’t run it properly, so I bought new NiMH batteries only to get the same complaint. She abandoned the camera to me and I switched to Energizer Ultimate Lithiums, which still work fine after more than 2 years. Now that I understand the situation, I’m sure the Eneloops will work well in the camera.
BTW, I think you meant ‘increasing internal resistance’ in this sentence: “…leaving your batteries in a charger for weeks at a time can also be damaging to batteries, lowering internal resistance…”
Regarding overnight charging, etc., best recourse probably depends on the charger characteristics. A good charger limits max voltage and drops charge current to less than an old-style trickle-charger. A bad charger lets voltage go very high and doesn’t reduce charge current to the same degree. So, do you have any thoughts about how ‘smart’ the charger circuits are in cell phones and computers?
Thanks for sharing your observations, Paul. Thanks also for catching that comment typo, which I corrected.
Regarding phones and computers, I know for sure that Apple makes very high quality chargers as there’s been a few articles about that, some of which I’ve read. So no doubt they switch to trickle charging when the battery is full (I’ve noticed they also slow down some when above 80% charged). I’d bet that other premium brands do too such as Samsung, Lenovo/Thinkpad, etc. but I haven’t looked into it so I could be wrong.
Trickle charging from a smart charger to batteries is fine for a few days but I’d be reluctant to leave batteries in for weeks at a time, as everyone recommends against that. I haven’t actually tested though to see what that does to batteries.
If you use low self-discharge batteries, there’s no incentive to leave batteries in the charger. They will be at full capacity or very close to it months after being removed from the charger.
I bought a Tecsun PL 380 radio about two months ago. I’ve used the charger function numerous times, but noticed that my AA Eneloops weren’t running long enough. I then charged them in the Panasonic BQ CC17 smart charger, and got far better running times. This Panasonic charger is impressive!
Hello. I wrote here just to give my personal experience and to learn. I bought my first charger in december 2009, a Digipower DPS-3000+ just because was in promotion with the Canon SX20 I ordered. Actually, I did not know anything about that matter. The batteries was of fast discharge so 4 months later I ordered the Sanyo Eneloop and that was magic for me.
The charger had a somewhat fast charge rate, 700 mA for 4 AA batteries with charging time about 3 1/2 hours, which sometimes caused batteries to get somewhat hat. However today I have an array of batteries: Sanyo Eneloop 8, Duracell Precharged 14, Ray-o-Vac Hybrid 8 and Varta 1.400 mA 2…a total of 32.
During this 7 years, the Digipower worked fine I think and I learned a bit more about and know of chargers like La Crosse, but the problem always is price…they range from US$30.oo to $55.oo. Looking in Amazon I find the Sunlabz $11.95; Panasonic BQ-CC17 with 4 batteries $14.99; Poweradd 903A $10.99…all with free shipping BUT in orders over US$49.oo.
Finally I ordered the EBL 920D in Amazon but directly from EBL…$6.99 and free shipping. This charger let charge 1, 2, 3 or 4 batteries, not just in pairs, has a discharge function, LCD display with charging process, not only lights, and a slow charge rate of 300 mA for 4 batteries. As you said 500 mA is a better charge rate. The 2 main reasons for my order was the possibility to charge 3 batteries (TOYS) and the price.
Excellent article and expect some advise. Thank you. Vicente from Barranquilla.
Hi Vicente – I took the liberty of correcting some of your grammar, as I can see that English is not your first language. haven’t tested the EBL 920D so I can’t really tell you what I personally think of it. It gets mixed reviews on Amazon, with some people satisfied, some not. The Panasonic BQ-CC17 charger is great so if you can get it bundled with some batteries, I think you’ll be very happy. It is available in many countries.
Thank you very much for your answer, and yes, I am Colombian. You are correct, with ALL products not ALL customers are satisfied, even the high end and expensive. The price is important because the money conversion is very negative for me an the cost of aditional shipment to my city (Amazon-Miami-Barranquilla plus custom duty). In better chargers to get free shipping I must place an order of full US$49.oo, very high for me…this in the price department. In features I liked I can charge 3 batteries instead of 2 or 4, and the display that I hope work fine. Aditional batteries? I have a lot allready. Quality? Durability? Only the time or aknoweledge people like you will answer that matter. However you can see that the almost unknow Digipower brand chargers allready works after SEVEN years. If you can obtain information on the EBL I will appreciate any advise. Thanks again and best wishes.
An informative read here.
I have charged EBL high capacity 2800mah batteries in the BQ-CC17 and they become very warm, maybe even hot. Panasonic wrote me saying it does NOT support batteries over 2400mah and that’s why they get warm. I don’t believe a charger would malfunction because of the battery capacity. Has anyone ever charged batteries over 2400mah in this charger? Do they get hot?
Scott – Thanks very much for the followup. I honestly had no idea that some chargers could have issues with the ultra-high capacity batteries. I have never tested any batteries that high so never ran into the issue.
Note that (arguably) the top battery reviewer on Amazon, NLee the Engineer, did not think that EBL’s 2800 mAh batteries are LSD batteries by any stretch after completing his testing:
https://www.amazon.com/gp/customer-reviews/R3TQXC56U39ZOO
Joe, thanks a lot for this article. It convinced me to finallly purchase a smart charger. I have a Sony BCG-34HH4EN charger, which unfortunately is a dumb one. Recently, I had to throw away four 900 mAh (850 mAh minimal) AAA batteries (labeled (CycleEnergy) after only year and a half, because the charger refused to charge them. The LEDs (one for each pair), started to blink a few seconds after placing the batteries, which is a signal they are dead.
The charger, being dumb and only charging in pairs and employing a simple timer, most likely overcharged the batteries, raised their internal resistance and killed them. To be honest, these Sony batteries were awful to begin with. They were not LSD and I doubt it they even had 850-900 mAh, because their longevity was a joke. I used them to power a wireless mouse and a keyboard, a pair for each one, but I had to charge them like every three or four days.
So I bought a pack with 4 Philips 1000 mAh AAA batteries (labeled MultiLife) to check if they last longer than the Sony ones. I hope this Panasonic smart charger I’ve bought helps with their longevity. I won’t even use my dumb Sony charger to charge these new batteries. I’ll probably sell it and only use the Panasonic charger.
Thank you Joe for this insightful article, I’m sure this charger will make me save money in the long run by keeping my rechargeable batteries health longer. Cheers from Brazil!
Joe, you said each bay has its own LED. I presume then that one can charge 1 to 4 cells and each bay shuts off independently of the others? Mark
Yes Mark. I only recommend chargers hat allow for the behavior you describe. Even the budget chargers.
The Panasonic BQ-CC16 charges at 500mAh per bank but charges two cells in half the time so must be bumping up the current to 1000mAh? Worth knowing if only inserting two cells and want to preserve their life. I could not find a UK supplier of the BQ-CC17 maybe discontinued?? as even the BQ-CC16 seems to be hard to find in the UK.
Overall a great little charger and excellent value as it includes 4 standard Eneloops.
Edmund – good question. The answer is that many of the top budget chargers these days do indeed charge at twice the rate when you insert 1-2 batteries instead of 3-4. I have not personally tested the BQ-CC16 or done much research on it. But funny you should post just now because just a few hours earlier, a new article on this site compares 3 budget chargers. One is the BQ-CC17 which I still love, and the other two are chargers similar to the BQ-CC16. Based on our testing (mostly Jim Hyden’s testing), we are now even more in love with the BQ-CC17, because compact chargers that charge at very high rates run the risk of overheating batteries. Heat dissipation is better in bigger chargers that have more space between batteries. Here’s the recent post comparing the 3 budget chargers:
https://www.filterjoe.com/2017/03/11/best-budget-chargers-bqcc55-fct344-bqcc17/
On the other hand, 500mA is a great charging rate so if you are sure to only use 3 or more batteries inserted at a time, I would be willing to bet that the BQ-CC16 is a great charger, based on Panasonic’s track record.
I got the blinking green lights tonight with Eneloop AAA’s and the BQ-CC17 charger.
Dougless – either your Eneloops have been recharged over 1000 times or you may have a defective charger. Are both your AAA batteries and BQ-CC17 brand new? If so, you should return them (if you purchased them in a bundle) for a replacement than works. It’s much more likely that the charger is faulty than the batteries.
Every single NiCd battery I’ve put in this charger has failed. Every single one. Otherwise, it works great with Eneloop NiMH batteries. Don’t get this charger if you use NiCd’s.
I have a Panasonic BQ-390 charger (…that still works after many years of use), it will do 4 AAs, or 2 AAAs. It was part of a n eneloop package purchased many years ago. I just recently purchase a BQ-CC-17 kit that came with 10AAs, and 4 AAAs as I needed more batteries.
Thank you for a most informative articleon the best enerloop battery charger, and I do hope this new charger serves me as well as my older, dicontinued, Panasonic unit did !
I have been using Amazon Basics AA batteries in a BQCC17 charger and Eneloop AAA batteries for some time now. AAA’s have been used extensively, without failure. The AA’s are now failing at an alarming rate, not having been recharged at any where near 500 times. I may have allowed the AA’s to completly discharge, don’t remember. Could that be a factor.
Joe, are you still moderating? I have a fairly new BQ-17CC charger which I use with AA and AAA Enloops. I frequently have the blinking green light issue; usually with AAA’s, but sometimes AA’s. Batteries have been recharged only a handful of times. All are fairly new, purchased in several lots over time.
A prior post suggested this may be a charger issue. However, the same issue happens when I then try with an older MAHA charger. Any ideas?
Hi Julian – I think you mean the BQ-CC17. Are the batteries all low-self-discharge batteries such as Eneloop or Panasonic? If you are getting blinking green lights on most of your AAA low self-discharge batteries, it is likely you have a faulty charger and should get it replaced while under warranty. On the other hand – if it’s regular NiMH batteries (the high self-discharge kind) that are by far more common at physical stores, the charger isn’t designed to work great with these lower quality batteries. They usually work ok with such batteries but in my experience, a BQ-CC17 charger in good working order will very rarely if ever show up blinking lights on a low-self-discharge battery.
How long might a BQ-CC17 last? I replaced my Eneloop batteries last year with Tenergy & they are not good this year… swelled up! So I am going back to Eneloop that had lasted for many years. How do I know when/if the charger needs replacement?
The BQ-CC17 is an excellent model that has withstood the test of time. Technology of AA battery charges changes very slowly so if you have a good one, you can keep using it for a very long time. I have several quality chargers over a decade old that work fine, though I think this model hasn’t quite reached the decade mark.
Generally, a charger will work perfectly until it doesn’t work at all. If there is a problem charging some batteries but not other batteries, that almost always means there is a problem with the battery (though some seemingly dead low self-discharge NiMH batteries can be revived).