Railfan Technology > Rechargeable AA battery challenges

If you are one of the many railfans that use a radio/scanner that uses AA batteries, you likely also have used rechargeable AA batteries to power those radios at one time or another.  Let me give you the bad news first.  Most all of the "reasonably priced" AA rechargeable batteries commonly sold today--including some brand name batteries--are manufactured in China, likely in a just a few plants, with the batteries sold under a multitude of brand names.  Over the past three years, I've tried out a number of these "Chinese" batteries.  I've been disappointed in the performance of all of them.  Recently, I did a deeper dive into this after acquiring the Uniden BCD160DN scanner.  This radio, likely because of its NXDN decoding circuitry, tends to be kind of a power hog, anyway.  Pair it with the Chinese batteries, and its battery life between recharges is pretty short.  So, I recently acquired a sophisticated battery charger that will fully discharge rechargeable batteries, then recharge them and report how many milliampere-hours the battery actually accepted.  That should approximate the rated storage capacity of the battery.  Key word there is "should."  Well, even with new or near-new batteries that I've tested, the actual storage capacity of the battery is considerably less--often far less--than the advertised capacity.  As an example, some new AA Chinese rechargeable batteries that I bought recently that I tested fared poorly.  They were rated at 3,300 mAH--they could only store 1,900 mAH!  Another Chinese brand that I tested was rated at 2,800 mAH--they actually stored only 2,100 mAH.  By comparison, I have some 13-year-old Energizer AA rechargeables made in Japan rated at 2,200 mAH that still store almost 1,800-1,900 mAH, after many hundreds of recharge cycles.

A common recommendation here TO is to use Panasonic Eneloop rechargeables.  That may be the direction that I go next.  The downside of the Eneloops is that their rated life is supposedly limited to a few hundred recharge cycles.  Thus, they are relatively expensive, but also may not be considered long-lived.  I would love to hear more from Eneloop users who have longer experience with the Eneloops.  Will they charge without damage on non-Eneloop chargers?  What is the actual life before failure that you get out of them?  Is their battery life in a radio between recharges satisfactory to you?  And, a more general question--how many people don't even mess with rechargeables and just use alkaline batteries and replace them when they run out of power?  Thoughts and opinions welcome.

I used to have a digital camera that had a voracious appetite for 2A batteries.  I found that Energizer Lithium were far and away the best for that use.  They're not rechargeable, though.  Like many others, I avoid Duracell like the plague because of their past leakage problems.  I tried rechargeables many years ago.  It was not a happy experience and I haven't tried again.
I use Members Mark (Sam's) for ordinary use.  Reasonably priced and reliable.
Anyway, my $.02
Paul

 

I also had problems with Duracell batteries leaking. I would not buy a Duracell battery again. I've had good luck with Eneloop batteries, although I don't use them heavily.

I’ve been using the Panasonic eneloop pro (rated 2450 mAh) NiMH batteries (made in Japan) in a Bearcat BC125AT successfully for several years. (The newest versions are rated at 2550 mAh.) They will charge without damage on an XTAR VC4 “smart” charger, although I have not tracked how many mAh a depleted eneloop will actually accept. However, anecdotally, I’d say they charge to a higher percentage of the rated capacity than anything else I’ve tried. For convenience, I tend to use the Panasonic BQ-CC17 'dumb' charger, because of its small size and easy portability. This provides a good 8 hours of run time in the BC125AT. On a long day, should the batteries die in the field, a pair of backup eneloops can be subbed in less than 30 seconds.

While I haven’t yet reached the end-of-life of the eneloop pros, reportedly, they can be recharged up to 500 times. I would note that I keep 3 pairs of eneloop pros dedicated for use in the BC125AT and cycle them through, so each pair has seen about the same amount of use.
 
While the eneloop pro batteries are available separately, a “package” that includes 4 eneloop pro AA batteries and the Panasonic BQ-CC17 charger is available from B&H for $30.84:
https://www.bhphotovideo.com/c/product/1047699-REG/panasonic_k_kj17khca4a_eneloop_xx_4_place.html
or
from batteryjunction.com
https://www.batteryjunction.com/catalog/product/view/id/2314/s/eneloop-hr-mqn10a4n-chr-4aa/category/208/

Edited: to include note about cycling 3 pairs of batteries through the BC125AT.

/Ted



Edited 1 time(s). Last edit at 07/28/24 14:40 by WM_1109.

FWIW, my experience using Eneloop Pro 2450mAh batteries in a BC125AT, along with using the Panasonic BQ-CC17 charger, has been exactly the same as posted above by Ted.
GK



Edited 2 time(s). Last edit at 07/28/24 21:33 by TheNavigator.

ReadingRR Wrote:
-------------------------------------------------------
> I used to have a digital camera that had a
> voracious appetite for 2A batteries.  I found
> that Energizer Lithium were far and away the best
> for that use.  They're not rechargeable,
> though. 

I have an older FujiFilm digital camera and I've been using the ~2500 maH AA size Panasonic Enerloops with great results.

Here are some not-so-scientific (no detailed data) observations comparing the Panasonics to other "higher capacity" AAs that are mostly mediocre, going back more than two decades:

During the NiMH capacity war between Panasonics and Sanyos, I noticed Panasonics sustained higher voltages while draining. Quite noticeable when flying electric-powered R/C aircraft, just by sound. Back then, the cycle life was about the same between those manufacturers, 500-1000 depending on the design - higher cycle usually meant chemical compromises for lower output voltages. But the more expensive Panasonics were getting an edge over Sanyo in voltage drop off and capacity for the same rated charge cycles.

Many "copycat" non-Panasonics tend to have quicker voltage drops, so their "higher" capacity ratings are likely deceptive, the "rating" based on different voltage thresholds.

On my FujiFilm digital camera, the copycats would do great for the first 2-3 dozen cycles, then I start to get "low battery" warnings much earlier than I wanted. No such phenomenon from the Enerloops for the first 100+ cycles.

What I've been doing is that I've been demoting the non-Enerloops for my cheapo 15+ year old Uniden Bearcat 72XLT scanner after they become sort of useless on my digital camera. They last long enough on the older version circuit board, with low battery warning beeps that last more than an hour. I suspect the old versions of the scanner had allowed lower voltage thresholds to operate.

Sometimes when I try to turn the scanner on with the non-Enerloops, they don't come on. That's from low starting voltage from natural chemical discharge of recharcheable batteries, more pronounced with lower quality ones. A 5 minute on the charger will revive enough voltage that it will come on, then the batteries last for a while. I'm taking advantage of the alleged lower voltage threshold on the old 72XLT.

So I haven't bought new rechargeables for about 2 years - still recycling the older ones until they become useless on my scanner, and in the meantime, Enerloops are happy on my digital camera.
 

I suggest reading up on how to treat NiMH batteries. Newer chemistry NiMH batteries don't develop memory and deeply discharging them just shortens their life. Leaving them to cook in the charger also shortens their life unless the charger is smart enough to shut off at full charge. You can't go wrong with buying a charger and batteries of the same brand.

radar Wrote:
-------------------------------------------------------
> I suggest reading up on how to treat NiMH
> batteries.

Memory problems were somewhat severe back in the NiCd days (Nickel Cadmium), but NiMH has been quite resistant to memory effect for at least a generation.

Like the lead acid batteries designed for deeper discharge, there are certain NiMH batteries that are chemically designed to handle that, too, and most consumer level AA batteries aren't that. Most modern electronic devices give relatively early warning for low battery charge these days, to minimize deep discharge situations.

In the old days, "smart" chargers would come with temperature sensors to measure fast charging cut off, made obsolete by chargers with more sophisticated circuitry (smarter firmware and memory) that can measure voltage differential over time. You know if your charger does it, when it cuts off charging earlier for batteries that are only partially drained, which should be most of them on the market today. For the ones I use, red light (normal charging), then green light (trickle charging). Good idea to remove the battery from the charger, if you don't expect to use it for a while.

Matching rechargeable batteries to their charger is a good idea. Using the Panasonic "higher operating voltage" observation as an example, if you use a lower quality battery in a Panasonic charger, the battery cutoff voltage might be slightly too high.
 

I have a four pack of Panasonic with the charger they cam with forever.  Use 2 at time in BC-125.  Haven't had a camera with AA in a couple decades.

I try to practic conservation.  I shut off if there is no need.  I scan one bank and LO spurious channels.  I will put on hold for one channel if all I need.

And carry a few regular AA just in case.

Bob

On another note my DSLR battery seems to last forever but I guess the mirorless is another story.



Edited 1 time(s). Last edit at 07/30/24 11:04 by robj.

I also swore off of Duracell.   I had two packs of them puke in the package they came in, not even used yet.   I used to like them, but won't touch them now.

Frisco1522 Wrote:
-------------------------------------------------------
> I also swore off of Duracell.   I had two packs
> of them puke in the package they came in, not even
> used yet.   I used to like them, but won't touch
> them now.

Me too.