Hangtime
Posts: 346
Joined: 6/5/2002
From: Babylon,
NY, USA
Status: offline
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AAAARRRGH!!
ok.. I can see we still need to talk. Pull up a stool, lemme get yah a beer, and we'll work thru this..
[QUOTE]Ok, what I think most people for example are doing though is going out and flying two or three flights, using a total of about 250mah from a 600 mah pack. Then coming home and charging overnight for, say 8 hours with a 60mah pack. That would be a 480mah charge in a perfect world (no energy loss) .[/QUOTE]
Ahh, ok.. here be da the real world.. packs absorb only about 60-75% at best of the mah of energy pushed at 'em by the charger. Thats why a correct slow charge routine (10%) is based on a 14-16 hour timeline instead of a TEN hour timeline. Long enuff to get the cells all topped up and equalized without causing any significant gassing issues. So, mr. battery pack instead of 480ma, only picked up around 300ma.. in other words; no problemo.
[QUOTE]So that would be an significant overcharge and result in reduce capacity. [/QUOTE]
Well, no; not really.. in fact gassing issues don't start cropping up at the 10% charge rate till well after 24 hours of continious charge... what you are using up tho is the chemical clock when extended 10% slow charging occurs, and this damage is about the least of all evils as far as potential overcharging of nicads go. I think all of us have left a pack on for a few days at 10%, and youll find a quick charge/cyle test routine shows only small losses in actual capacity, 10-15% at the most, with most of this recovered after a correct charge cycle routine.
The most fragile nicads, like the pushed capacity AA's used commonly in 1100ma Tx Nicad packs and over 800ma AA sized Rx packs really lose capacity fast when pushed to long with a slow charger, or too often with a peak charger. Big sub-c cell Rx packs tend to shrug off 10% charge rate overcharge conditions like it didn't even happen.. much lower internal imedence and lots more relative surface plate area to dissipate heat over.
[QUOTE]And this is where I think most people find the need to cycle their batteries every now and then and thus continueing the myth of "memory". [/QUOTE]
Well, sure; I'd expect anybody that's whipped up on their pack with a significant extended overcharge no matter what rate it got hit with, to cycle and charge a couple of times correctly to be damn sure he didn't significantly cripple his pack, and when the numbers come back he prolly figures he 'cured memory'.. much easier than admitting "geeze, thank god these nicads are tuff, I coulda killed the poor things with that 3 day charge." 
[QUOTE]The best thing to do I imagine would be to slow peak charge. The Dymond ST will do that btw. [/QUOTE]
ARRGH!! NO!! PLEASE< NO>> SAY IT AIN'T SO; JOE!!
Look, didn't yer daddy tell yah that just because yah can go jump off the cliff, don't necessarily make that such a hot idea??
Seems like every chip controlled charger I see commin out now has some pretty wild features desigined to kill batteries in the hands of the mis-informed. Must boost battery sales or somethin.  NO, fer crissakes, don't use yer peak detection charger at rates below 1c.. if fact, I'd use 1.5c or 2c so the charger sees a nice clean knee in the voltage curve and shuts off appropriatly. If that pack is even a lil outta balance, there'll never be a clean unff 'knee' in the voltage curve to trigger the shut off.. and big cells may never show a voltage deppression when they reach overcharge at 1c rates and lower. So DON'T 'slow peak charge' if ya like yer batteries.
How we doin, Buddy?.. hey, if yer gettin up, grab us annuther one of them beers... and check that charger while yer at it.
[QUOTE]But that is just me.... [/QUOTE]
Thats, us; ...a coupla wild 'n crazy guys...
< Message edited by Hangtime -- Aug 4 2002 10:36PM >
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Steve Anthony
www.hangtimes.com
NoBS Batteries
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All Forums >> Radios, Batteries, Clubhouse and more >> Batteries & Chargers >> Are Peak Chargers Killing my Batteries? 
Are Peak Chargers Killing my Batteries? - 
I feel even worse when some $1.49 chinese framitiz lets go and i paste a bird because somethin that shoulda worked didn't. 
!! 
Are Peak Chargers Killing my Batteries? - 
batteries - 
Just the facts, Ma'm. -