I've been doing a lot of reading wrt battery cell testing, but have only
seen one (affordable, reasonably priced) recommendation for testing
rechargeable cell ESR.. the Bob Parker ESR Meter.
http://www.flippers.com/esrkthnt.html (near the bottom)
http://www.prc68.com/I/BatTst.shtml#EVB
I would like to be able to determine (actually see it) if zapping new nicad
cells improves (lowers) cell internal resistance, or to just check cells for
a parameter other than voltage.
From what I've found, zapping new NIMH cells isn't worthwhile, or attempts
have been inconclusive.
I want to avoid any testing equipment that requires a computer. I also don't
want to build battery packs with the newer fuel gage technology electronics.
I'm not using the cells for any high ouput/endurance applications, I'd just
like to have a visible indication of a cell's condition.
Relying upon a tester that includes a small load resistor and a meter
doesn't give any worthwhile indication of a cell's condition.
I have a charger/discharger made by MRC for the RC hobby, with fully
selectable settings for charging/discharging rates for up to 8 cells. The
MRC Super Brain 977 has a lot of features for battery packs, and a test of
condition related to discharging at 1/5th the capacity of a cell or the
entire pack. The user monitors the voltage as it drops.
http://www.modelrectifier.com/search...ew.asp?ID=1908
I'm not trying to restore/rejuvenate old, used, weak cells. I want to build
battery packs with high capacity cells (NiMH 4500mAh sub-C, 10000mAh D) for
some of my low current demand) gear, so that one pack will last for extended
field use (a full day, not weeks) without needing pack changes.
I'll use dedicated chargers for the different packs.
I use sophisticated smart chargers for my cordless tool battery packs, and
avoid using low quality chargers.
I have Sencore Z-meters but I don't think they'll give an ESR reading on a
charged cell.
See the effect of zapping
http://www.buchmann.ca/article23-page1.asp
There are many more examples of zapping new nicad cells online. Recommended
capacitor values and voltages differ greatly.
There are a lot of opinions online that are very dated, related to battery
types that were available years ago.
A trickle maintenance approach to eliminate self-discharging effect of NiMH
cells
http://www.ka7oei.com/nicds.html
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Cheers,
WB
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