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Adventures in Rechargeable Batteries


I also had a BC-900 (v33), which melted itself while charging 4*AA cells (the ones supplied with the charger) at the lowest current setting - the first time it was used!

Switched to Maha, had no problems.


I find it weird that the BC-900 has a temperature sensor but still gets very hot. It’s very simple logic to have it stop charging at a pre-set temperature.

I like my Ultra rapid charger that has an LCD readout for each battery as well as a discharge function.

There is a cool product called the Noma pocket power charger (found at Canadian Tire in Canada) that accepts 4 AA batteries and has a USB plug on it plus 8 telephone adapters for charging anything that uses a USB plug for power ()eg: ipods. It comes with low end 1400 mAh NiMH batteries, but you can put in your own.

I use it with a USB power adapter for the Nintendo DS. It has a Datel Games and Music card which has a MicroSD solt so I can listen to mp3 with it. Cool feature - it has a “time slider” so you can go pack to a half-listened podcast or audiobook and not have to play “fast-forward and guess” for 2 minutes, just tap roughly where you left off, then adjust with 2 or 3 more taps. This is good if you go to sleep listening to audiobooks.


Great article, but some things about the article and especially the comments, make my skin crawl.

Firstly - “The world runs on AAs”, and even more disturbingly, those who actually recommend cameras and gadgets that use AA in preference to Li-Ion. This is totally insane. Li-Ion is a far superior technology than AA NiMH. If given the choice, why would you choose the AA version? The “proprietary battery” issue is far outweighed by the better performance, and the fact that the chargers are better and specifically designed for those batteries.

It’s hard to believe some of the design choices. The Xbox wireless controller uses AA batteries? That’s insane. Why doesn’t it use a lightweight, compact, high-performance Li-Ion battery?

I recently needed to purchase a wireless mouse. I could have purchased an Apple Bluetooth mouse. But unfortunately, it used AA or AAA (can’t remember which) batteries. Instead, I went for a Logitech Bluetooth mouse, which came with two lightweight Li-Ion battery packs, and a USB charger. Of course, it requires a USB Bluetooth dongle and won’t work with the Mac’s built-in Bluetooth - but I’d rather use up a USB port or add a USB hub than have to fill a goddamned mouse with AA/AAA batteries, whether they are rechargeable or not.

When it comes to cameras, there is no competition. Why would you buy a camera that took AA/AAA batteries? It makes no sense. If you are doing any kind of strategic planning with your tech purchases, you shouldn’t have very many devices (apart from DVD remotes) that require those things. MP3 players with AA batteries? Ridiculous.

Now, in my professional work, there are still a few devices that require AA or 9v batteries. But many of those suffer performance issues with the 1.2v of a rechargeable battery. But the really important ones (wireless microphone transmitters receivers) tend to use 9v batteries anyway. That’s a whole other kettle of fish. But how many people use professional microphone systems?

I don’t know about you, but in my world, the AA/AAA battery is becoming largely irrelevant. If it isn’t in your world, then maybe you need to assess what you are doing wrong that leads to a reliance on this cell type?

The other issue that disturbs me about the comments on this article are all the people who are religiously talking about the “memory effect” as if it were something real. The “memory effect” never actually existed. Not for Ni-Cad, not for NiMH, not for Li-Ion. It’s a complete myth, and those who believe in it are similar to those who believe in fairies, ghosts, or the boogeyman.


@Harvard Irving others:

What is with the hate for NiMH AA batteries? Are those who espouse Li-ion rechargeables really that eager to spend more to put single-task devices in their houses? Are those who are using AAs but find NiMH “undependable” really that eager to produce that much waste by using mass quantities of alkalines?

I’ll take a couple of small, portable ‘tube-velopes’ (8xAA) of Eneloops and a couple of Lightning Pack 4000Ns on a trip any day, fueling our Canon A80, A630, and Pentax K100D Super. Back home, I’ll put the AAs in our 2 LaCrosse BC900s and top them off - because even after a heavy day of shooting, the 4xAA usually aren’t discharged and don’t require changing out.

We’re not doing anything ‘wrong’ by choosing to rely on a single, universal cell type and charger(s). Did the Li-ion users ever consider assessing what ‘wrong’ choices they’re making that leads them to need so many different proprietary chargers and batteries? (The product makers don’t think you’re wrong at all, by the way - they LOVE you. They get to sell you a new charger and new spare batteries every time, after all! I suspect this is part of why cameras that can be fueled with AA or AAA batteries are getting rarer…)

Please note that the reports of problems with the BC900 are necessarily over-represented in reviews - the many, many people who are using them without issue generally are not the ones who take the time to post a review. I have two and have never had a single overheating issue (though I have taken some precautions, e.g. keeping them on textured silicone mats to allow airflow beneath).

I’d be the first to say that the user interface on the BC900 is a pain, with a steep learning curve, but just take a look at this (about the Maha C9000 charger) and imagine having to do forty-eight button presses to configure a set of 4 batteries to charge.


The BC900’s no great shakes, but the C9000 is a textbook example of testing an interface with too few users. (Did they test those functions with ANY users, I have to wonder?)


“Seriously, just look at this thing. It’s a geek’s dream.”

"Please make sure that you get this charger with v33 firmware. "

Yep, geeky indeed. :slight_smile:


@Harvard Irving

Sennheiser and Lectrosonics both make wireless mic body packs that take AA batteries. They chose AA batteries because they’re ubiquitous. If you happen to show up at a venue with dead Li-Ion batteries, you’re screwed. It’s not like you can go out and buy a fully charged Li-Ion battery pack. You can buy AA batteries pretty much anywhere.

I don’t know anyone who would use rechargeable batteries in this situation, anyway. If you’re doing an important show, you should be using fresh alkaline or lithium batteries.


Hi all…I have noticed the many comments about using NiMH batteries in remote controls. Will using these rechargeable batteries hurt the remote? I am currently using Rayovac Hybrid.



Received my BC-900 today

Firmware version: 35
4x2600mah aa included
4x1000mah aaa included

So far so good.

I too have a bit of battery knowledge: 8 month old demands a lot of camera attention and I have been flying electric RC airplanes for 5 years. I’ve used every battery chemistry except A123 cells.

I was going to get the Duratrax Ice charger but it costs over $100 used on eBay. It charges most batteries, but doesn’t give individual attention that this charger gives. Funny how RC folks charged NIMH at 1C - 1.5C because we’re in such a hurry to fly. I only use Lipos now for the hobby but now I have to gove more TLC to these AAs for the camera. I bought my camera specifically because it uses AAs. Can’t stand the expensive, proprietary batters some cameras force on you. Plus, traveling with lipos is becoming more difficult with airline restrictions. You’re supposed to fly with one lipo battery attached to your device and only one extra. Bad news.


Where did you buy yours to have the firmware version 35?


of all places…amazon.com

The 2600 AAs that came with it have a true capacity of 2450-2550mah.

Amazon also has an 8 pack of 2100mah Hybrios for about $15.


Re: Adventures in Rechargeable Batteries

I recommend the Rezap battery charger. A new Pro version of the Rezap is available which you can take on the road. i.e. use in the car.

For rechargeable batteries I recommend the Varta Ready2Use 2100mAh NIMH batteries in AA or AAA size (adapters are available for C and D size). These batteries have LSD (Low Self Discharge). I’ve used 100’s of the Ready2Use Varta batteries in battery packs over the last two years and NONE have failed. They not only maintain their charge but also their capacity over many more charges than other batteries I’ve tried!

I prefer devices that use AA or AAA batteries because I can just swap them over when they run out … if you’re out in the middle of the Australian bush and your lithium battery runs out you can hardly plug it into a tree, can you?

If I’m out jogging and my MP3 player runs out I just carry a AAA battery in my coin pocket and swap it over … try that with your Ipod!


GREAT ARTICLE , Thanks : )


I got one of these for Christmas last year. I guess I failed the geek test because I ruined my batteries with it. I had 2000 mah batteries, so I set it to refresh for the 200 that appears after 700 thinking it MUST mean 2000. doh I reduced the capacity of my batteries.

Please tell me how a charger that only works up to 1800 on paper and only offers settings up to 700 can possibly work for batteries that are 2600 mah +. I’m thoroughly confused on how to operate this blasted thing. It gives me choices of 200, 500, 700 and that’s it. Is it because I got a 900U instead of a 900?


Hi Jen

I think you’re confusing the ‘capacity’ of your batteries (mAh) with the ‘charging rate’ (mA) of the charger.

You divide them to approximate how many hours it will take to recharge from empty,
example:- 2000mAh battery at 200mA rate - 2000/200 ~ 10 h(ours) to recharge.


that paperclip trick totally works! I had 4 AAA’s for my remote and one was showing NULL. I did the paperclip trick and it not only started charging it shows that the battery was not completely dead.

Now can someone please explain this magic trick?

Is it something specific to the La Cross BC-900 or does this work on any charger? I have a few other old chargers that only show a blinking red led when a battery will not take a charge.


The paperclip is shorting the two batteries together, forcing a small charge to build in the null battery from the good one. This charge will last for about an hour, but is enough to fool the charger’s brain into thinking there is a valid battery there. If the voltage is too low, the charger thinks there is either no battery there, or its reversed, or bad.

So there.


Is it something specific to the La Cross BC-900 or does this work on any charger? I have a few other old chargers that only show a blinking red led when a battery will not take a charge.


I got a pair of Sony 2300 mAh NiMH AA batteries with a Sony digicam a few years back, and seeing as my cordless mouse also took AA batteries, one day I figured I would try the NiMH in my mouse as it was ridiculous eating up 2 AA batteries every few weeks. I found they worked quite wonderfully in my mouse and lasted longer than alkalines.

Then one day I saw energizer NiMH in the store and knowing I needed a few more AA batteries, I bought them. They were a complete waste as they never lasted very long at all. So I went to the Sony Store and bought a few more AA batteries(1700 mAh), which outlasted the higher rated energizers by a long shot.

I’m happy to say all 6 of my NiMH batteries are still working great 4+ years later. I no longer have that sony digicam, but I do have a bluetooth cordless keyboard where the 1700 mAh batteries last a good few months before needing charging, even with greater than 8 hrs a day usage. I can even use them for a good few days after the keyboard says the batteries are empty so I have a few days to remember to put them in the charger overnight.


can charging regular lithium batteries (by mistake) kill your digital camera?


Jeff’s full-time blogging? What about the super-secret startup?