Pulled the D cell and 9V battery from my Simpson 260 today as I'd bought a pair of Tenergy Centura D cells the other day at Micro Center and they finally finished their break in cycle on my charger. (I still need to get a 9V NiMH charger... right now I'm just using the 9Vs out of the package, which is less than optimal, but when you don't have something you don't have it.)
I know I just replaced the D cell in there within the last year, but the "Duracell Procell" alkaline cell in there WAS LEAKING! Dated good until March 2014. Fortunately it was just a little bit of creeping white powder on the negative end around the wrapper, and never even got to the contact in the battery holder. *whew!* (It also means that the cell was probably 5-6 years old when it was installed as Duracell advertises a 7 year shelf life. Don't know where it came from, I probably got it from roommate's battery stash. But still, if it says good until, I expect that to mean good until!)
Now I realize that I am probably very hard on cells as these are my TOOLS and as such may end up being used in a hot garage, left in the trunk of my car both parked in the sun and driven over rough roads etc.
- but still... I've had a LOT of leakers this year and I don't remember ever having a run of luck this bad with cells.
I suspected that if I was going to have a problem it would be with the "9V" battery as the NiMHs that I bought were the 7 cell version for a nominal 8.4V. Well, I was wrong - the meter zeros fine on the high resistance setting (which uses the 9V battery) but I'm almost out of adjustment (maybe 1/4 turn left) on the Rx1 scale which uses the D cell. (the Rx100 scale also uses the D cell but adjusted fine with a good amount left on the pot.) But it seems that that is just the way it is... I checked it with a D cell out of my mag lite and measured the open ckt. voltage of that cell right at 1.50V and only had to back the pot off a tiny amount to re-zero on the Rx1 scale. (OC voltage of the NiMH is just about 1.40V; they're nominal 1.2V cells. Not sure why a D cell is used for the Rx1 and Rx100 readings, I doubt it flows that much current... must just be so you don't have to replace it so often, or maybe it's just a legacy from back when most cells were carbon-zinc, but I didn't think the 260 design was that old.)
The Centuras did test out at just about their rated capacity (8000 mAh) on my charger, although they showed up with only about 1/4 charge. So the one that I'm not using I'll have to check capacity on them in a couple months to see if they are truly low self discharge. Tenergy does not advertise them as "precharged" or "ready to use" however, so they may just ship with a minimal charge on them.
DAYAM. One more device left with alkalines in it... that's the mag-lite that I borrowed a cell from to test. At least those aren't leaking... yet.
I did get some of the cell adapters from the Chinese guy; paid him for them yesterday. So it'll probably be at least a week or two before I see them; I'll let you all know how they appear/function when they get here. I have enough spare AA NiMHs that I can use the Mag-Lite to store them; then at that point I will have NO alkalines left save for ones stashed and not in devices! You've no idea how happy this makes me, my inner greenie weenie is all warm and fuzzy and I've just been getting PO'd at alkalines so much lately that I can't get rid of them fast enough.
nate