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Old 04-26-09, 08:13 PM
  #8  
prathmann
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Originally Posted by PaulRivers
From what I've read around, the biggest obstacle for me about a fast charger is that the really fast chargers don't 100% charge the battery. That last 10-20% charge needs time and a low current to get it (apparently, but what people have written about testing capacity after charging with different chargers).
I think that's true, but I don't see how it's an 'obstacle' to using a fast charger, especially since many of them automatically switch to a trickle-charge mode after the fast initial charge. If I need to get some cells charged in an hour then I'm happy to get them to 90% charged in my fast charger instead of only 10% charged using a slow charger for an hour. OTOH, if I have more time for the charge then the fast charger will switch to trickle mode and will finish getting them up to 100% charge.

BTW, the numbers in the OP don't look consistent. If the charger is rated at 700 mA then it'll take about 4 hours to fully charge the 2500 mA-hr cell (2500 mA-hr / 700 mA plus a little extra to allow for inefficiency) and the 1600 mA-hr cell would take almost 3 hours. So it really isn't a 2-hour charger for cells in that capacity range. As long as it is properly sensing when the cells are at full capacity and shutting off at that point then I see no reason to get a different charger - esp. one that's even slower.
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