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Adventures in Rechargeable Batteries


I did a bit of googling to find out where I can buy the charger too and found lots of reports of this charger actually melting.



and here:


That is quite scary, most people leave their chargers on during the night or when they’re at work. The last thing you want it coming back (or waking up) to a house on fire.


So let me be a smartass for a moment. Did you also run out and post an article on the internet about how great the rechargeable batteries were in 1998, like you’re doing now?
Aren’t you unwillingly participating in the evil marketing? Caveat Venditor, Jeff, Caveat Venditor!

That’s why I’m a geek lagard - I like the toys, but i want to see everybody else screw it up first. I’m a shrewd geek.

Thanks Jeff!


Can you use the BC-900 as a poor mans VOM? IE can you put a alkaline battery in the BC-900 just to check the voltage level without charging it (or at least without harming it assuming you pull it out after seeing a reading)?

oh, and fwiw I remember reading that same dvorak article back in the day.


I slapped together a low-power pc, 10 recharchable batteries and a head-mounted display. Now I’ve got a “laptop” which runs on standard batteries for 6 hours.

The batteries I used are D-size cells with 7000 mAh, five euro each.



How’s this for a poor man’s VOM http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=92020


I use Lenmar’s 8 minute charge batteries. They charge in 8 minutes and seem to hold their charge for a long time. They need Lenmar’s 8 minute charger if you want to charge that fast.

For other batteries look for long memory batteries which means they hold their charge when not in use for a longer time.


If you really like charging batteries, you should get into electric aircraft - big monster batteries with high voltage and discharge rates, and they are not exactly safe :slight_smile:


Anyway… I know a little bit about batteries and I’m not sure if this is what you’re saying or not, but the capacity posted on the label is not ‘misleading’ if you understand what it really means. It has nothing to do with the self-discharge rate… it only means the battery can deliver that much power over the course of its discharge cycle… which it does. If you weren’t there to use the power when it came out… that’s your problem. NiCad and NiMH cells have fairly high self-discharge rates, so we tend to avoid them on model airplanes because you have to charge them right before you fly, and that is inconvenient, and they are heavier than Lithium-Polymer type batteries. They do have higher discharge rates though, so if someone needs 100 amps or something, they do use NiCad, NiMH or “A123” cells.

We generally use Lithium-Polymer batteries in aircraft, but they need to be handled with care as there is a risk of explosions and fires, so they are not viable as a supermarket-type consumer item. It would be nice if they could be made a little safer though, because they have very low self-discharge rates. I’ll charge mine up and let them sit for months sometimes and they only lose maybe 2-5% of the charge, over the winter for example.



And they have very little memory effect! I really hope they get the safety issues of Lithium-based rechargeables worked out so we can see these become more consumer friendly. The LifePO4s look good except for their crappy capacities.


I got an Energizer recharger (http://www.amazon.com/Energizer-CHM4FC-Battery-Charger-Energy/dp/B00000JGNB) on sale at Best Buy a couple years ago. Charges AAA, AA, C, D, 9V NiMH and NiCd which is nifty. It works for me. Of course, I don’t think they even make devices any more that take a C or 9V, but you know… maybe one day.


This thing must have quite a learning curve (or maybe it’s just unsuitable for “slower” people). Lots of reports on the Amazon reviews of the thing melting, batteries melting, causing fires, etc. Also complaints of it not working as well as it should – undercharging batteries, inaccurate displays.

I usually try to read the good and bad reviews about something, and every product seems to have some bad reviews., A lot of times it’s trolling and people with defective products, and once in a while it’s someone with a real complaint. But these seem legit enough to be worrisome. I understand the v32 and v33 firmware issue, although there doesn’t seem to be any good way to ensure you actually get the 33.


I have this charger!!! I’m glad it’s being reviewed so positively. I’m so glad I made the choice to buy this charger!


Read the Amazon reviews: the LaCrosse BC-900 charger has the potential to burn down your house. For this reason I did not buy it.

Do get the Maha chargers (thomasdistributing) which also charge controlled (measuring voltage and battery temperature) and are even cheaper than the BC-900 charger.



I must have thrown away like 6 good batteries in the last year cuz my BC-900 said null :frowning: …awesome tip, no more null display for me…


Awesome article. Thanks for the info!



The BC-900 does have a bit of a learning curve. It’s more than just a charger, though. It’s an analyzer/conditioner as well, and as such is the least expensive charger I know of with those capabilities.

The Maha equivalent, the C9000, is highly regarded and slightly more featureful and safe. It’s more expensive, though.

Maybe a better idea for those not wanting to mess with the complexity is Bart’s suggestion of a Maha. I’ve heard the C204W and C401FS are great chargers, but don’t have personal experience with them.

Regarding the BC-900, there is another workaround that I’ve been trying. Some people on CandlePowerForums suggested putting a small fan to blow on it while charging. This may not be practical for some, but it’s working for me. I just got through running mine for 5 days straight with no problems this way. It keeps the charger and cells at a very cool temperature. The drawback is, it becomes even more important that you don’t charge at a low rate. You need at least C/2 so you’ll have a nice pronounced voltage drop when the battery reaches full charge. Otherwise, you’ll miss termination and pump way too much into your batteries.


I’ve been using rechargables for years, starting with my old nomad mp3 player that used AAA’s. The only problem I have with rechargables is their voltage of 1.2 versus the alkaline 1.5v.I have 3 mindstorms sets that need a combined 18 batteries but running them with rechargables makes the motors run slower.
(after a quick google search): http://www.philohome.com/nxtmotor/nxtmotor.htm

I still use them on my xbox 360 wireless controller but I wonder if the rumble on them is less than they would be on alkalines. I know the rumble on a wired controller is much more pronounced compared to the wireless, yet to try 1.5v vs 1.2 v.
Perhaps I’ll start recharging alkalines, unfortunately they don’t last through many recharges.


Oh my god, Meyer is in da house, this interwebs is crazy stuff.



No, that is not a poor mans VOM. It requires a 9V battery. I have a VOM now that I use a couple of times a year but the 9V battery is always low. Pretty much the only reason I use it is to test AA and AAA batteries and pretty much the only reason I buy 9v batteries is to power the stupid VOM.

Does the phrase “theres a hole in the bucket dear Liza” mean anything to you?


I learned to loathe rechargable batteries after using a sony digital camera that used AAs. My theory was that if the batteries ran out I could always hit the store or anybody had AAs, right?

The problem was that the camera would drain a nice newly recharged battery in a few hours, so you just got used to carrying around a few extra AAs. I’ve since switched to a Canon with a much nicer rechargable LI battery, and I almost never have problems.

I think part of the problem might have been our crappy battery charger, and the geek in me is just drooling over that BC-900 so I just might give them another shot! :slight_smile:


Ordered, enjoy your commission :stuck_out_tongue:

I also ordered some choose your own adventure books for my son. Get out of my wallet!