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E Z Peaces

wrote:

Are you trying to skew what I am saying by leaving out a time
constraint on charging????
Panasonic specifically recommends against trickle charging except on top
of a fast charge.

Again you are skewing the facts again. Panasonic's talk about
overcharging with trickle charging is assuming that the charger
stays on. Which I do agree with.

It's a fact that Panasonic simply says not to trickle charge.

They suggest trickle charging with a time limit. So do I.

The only trickle charge they suggest is on top of a fast charge. You
seem to say a trickle charge is whatever you happen to get from a cheap
charger. Are you calling .1 lt a trickle charge? Panasonic says that's
2 or 3 times bigger than a trickle charge. They recommend a timed .1 lt
charge only for standby batteries and they recommend that the charger
turn on only when the voltage falls below what they specify.

If you buy a cheap charger, don't even check the current, and run it 2
hours a day, how can you possibly expect not to overcharge?
Because the charger is intentionally so weak that it can't harm the
battery in two hours no matter what the state of charge.
Now I remember why I got a fast charger when I got NiMH cells. My NiCd
charger would have been .05 lt for the NiMH I bought, and NiMH may not
charge at that current. Panasonic's chart shows that except at cool
temperatures, they won't charge fully even at .1 lt.
I didn't buy hybrid or low-self-discharge batteries. I bought the
ordinary NiMH cells available 11 years ago, and they still hold a charge
for months.
Define months. Non hybrids won't hold a full charge this long without
some sort of maintenance charge.
Lunar months are about 29.5 days. Calendar months are 28-31 days.

Good try. I said define monthS, with an S......When you speak of non
hybrid NIMH batteries and you say "and they still hold a charge for
months." What charge, and how many months?

Since 1980, if I wondered about the condition of my nickel cells, I'd
charge each one and use it to power an analog clock while shunted with 2
ohms. That would tell me a cell's capacity. Then I'd try it again
after letting a charged cell sit on the shelf a week. That would allow
me to calculate self-discharge.

How about you? Have you tested the capacity and self-discharge of cells
exposed to current from a cheap charger two hours a day over a period of
months or years?

You don't seem to be a reader. I said I expect my old NiMH to hold a
charge 6 months. I've been using wireless keyboards 40 months. I've
recharged batteries 5 times. That would mean a pair of NiMH 10 years
old holds enough charge for a wireless keyboard about 8 months.

I've also done very well with NiCds after going to fast charging.
Either type of battery will probably power my 800ma flashlight after
several months on the shelf.

Panasonic shows that their ordinary NiMH cells may retain a 90% charge
after 4 weeks. That could mean 50% after 6 months. Even after 11
years, I expect that of my NiMH cells. Using a manual .1 lt charger, my
NiCds wouldn't hold a charge that long unless they were pretty new.