Between the two analyzers, the Maha is easier to use, but the Lacrosse is smaller and better for taking on trips.
Today I semi-retired a 20 pack of Lenmar 2500 mAH cells which I bought two years ago. They have been used in virtually every piece of equipment I own that take AA cells and have worked beautifully. Even after 2 years they still provide about 70% of rated capacity. It is important to note that their good performance is because they are regularly used and frequently charged. I am retiring them mostly because their plastic casing is shredding and I am concerned about short circuits between cells.
And Today, I received their replacement: a 20 pack of Sunpak 2650 cells. I'd first tried Sunpak batteries when they were loaned to me by Andrew D. for use in my tech flashlight. I was impressed at their capacity and their better than average self-discharge rate. I hoped these cells would do as well. They were purchased from Adorama at a cost of $32 including shipping. Just out of the box, however, they offered me a new disappointment. Two of the cells were DEAD. No voltage, could not be charged. I'd read reviews online when people wrote about Lenmar and other brands of batteries having DOA's but I'd never had it happen to me. Two out of twenty.
When you get a shorted Nickel Cadmium (NiCd) you take it to a power supply and zap the hell out of it, in order to break up a crystalline structure which has formed in the electrolyte. So I thought I'd try the same thing with these, seeing as how they were destined for the trash bin. Using an Agilent U8002A bench supply, I set voltage at 12v and current at 500 milliamps. The first one started taking a charge (from zero volts) very slowly, then when it hit about 200 millivolts it suddenly ZOOMED up to 1.4 volts. At that point I put it in my Lacrosse charger and as I write this, it is still charging. The second battery stayed dead. Zap, zap zap. At 500 milliamps it wasn't making a dent. So I thumbed the current first to 1A (zap zap zap, nothing) and then to 2A. On the second zap, the battery broke free and started slowly charging! (I was prepared to take the Agilent all the way up to its rated 5A. I'm glad that wasn't necessary.)
So... both "dead" cells are now charging and if my guess is correct, the discharge tests on the first run will suck, but then after the 3rd or 4th cycle they will be as good as the other 18 batteries.
If you don't have a bench power supply and want to see if you can un-short your NiMH batteries, here is something you can try. It is (mostly) harmless, so even if it doesn't work you shouldn't lose anything. Take your dead cell and a perfectly good fully charged one. They must both be NiMH. Put them in your palm parallel, so both (+) buttons face the same way. Take two quarters (or other large coinage) and put one each across the terminals at each end. Hold firmly for about 3-5 seconds -- but not longer than 5 seconds. You may or may not see a spark when you do this -- don't worry about it. Afterwards, put the "dead" cell into a charger and see if the charger now charges it. If not, repeat the procedure with the quarters, maybe using a different fully charged battery.
I guarantee this will work for some, but probably not all, DOA cells. It doesn't hurt to try, and if it works you've rescued your investment! Just remember that recovered DOA cells will need 3-4 charge/discharge cycles before they run at capacity.
And bear in mind: NiMH cells only hold effective charge for about two weeks. Charge your batteries just before using them if you want best performance. (This does not apply to those newer ultra-slow discharge batteries like Sanyo Eneloop. Charging these every 6-12 months probably adequate.)
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