How are these Panasonic AAs?

kramer5150

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I have had these for a few years. They have been largely unused, maybe 3-4 recharge cycles max.

Whats the scoop on these? good/bad? I don't need an LSD cell for this application since this spot light project has a built-in trickle recharge circuit that cuts off the charge at around ~3.8 volts.

I'm just wondering how much improvement would I see upgrading to new cells. I don't want to just upgrade for the sake of upgrading, if there's not a significant performance benefit in doing so.

FWIW, these cells are 2300mah and made in China. Current draw for the project is 1.4 amps split between the two clusters.. so .70 amps per cluster.

pic here...


all comments welcome,
thanks
 
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Mr Happy

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If they are a few years old and have seen little use, then a consideration is that they may not be the same cells now as they were when they were freshly manufactured. NiMH cells tend to fade and die if they are stored for a long period without being used. It would be sensible to test them if you can to see what capacity they currently have and how long they hold a charge.
 

kramer5150

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OK thanks I will play around with them some more, cycle them a few times etc. I had them in a 6-cell 7.2 volt arrangement, powering a 6D mag incan bulb, in a cheap plastic light but that light hardly ever got used. The cells were healthy about a year ago when I last touched that project.

thanks:thumbsup:... anyone else?

I was hoping someone would chime in with some glaring deficiencies or poor prior experience... high resistance, poor durability, unusually high self discharge... stuff like that.

thanks!
 

45/70

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I was hoping someone would chime in with some glaring deficiencies or poor prior experience... high resistance, poor durability, unusually high self discharge... stuff like that.


It almost sounds like you're looking for an excuse to get rid of them! If so, these last few days, I know how you feel.

I've been analyzing some DynaCharge 1800's. I bought these in mid 2000 so there 8 1/2 years old. None of them check out less than 80% capacity. Still, they only average about 1.1 Volts through a 1 Amp discharge, and they aren't the best cells at keeping their charge, but hey, they still work! I just can't seem to get rid of them! :)

On another note, I don't know what kind of trickle application you have going there, but as you probably know, a constant trickle isn't too good for NiMh cells. If you have some other setup, it may be OK.

Dave
 

kramer5150

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corrected my post a little.
I'm just wondering how much improvement would I see upgrading to new cells. I don't want to just upgrade for the sake of upgrading, if there's not a significant performance benefit in doing so.

I'll play around some more with them over the next few days.

thanks
 
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Fallingwater

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NiMH cells tend not to like trickle charging much. They'll survive for a while, but they'll lose capacity over time quicker than if charged normally.
 

kramer5150

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NiMH cells tend not to like trickle charging much. They'll survive for a while, but they'll lose capacity over time quicker than if charged normally.

OK thanks, I'll add a second charge plug (deans) so I can charge them at a higher rate using a higher quality charger. I can still retain the OEM wal-wart charge circuit for when I travel with it.
 

Mr Happy

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Specifically, they don't like constant-on trickle charging. If you trickle charge them until they are full and then stop, that is OK.
 
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