Re: Dead pack and NiMH cells Message #17 Posted by Andrés C. Rodríguez (Argentina) on 28 Feb 2001, 10:26 a.m., in response to message #16 by Steve (Australia)
You can charge at C/4 IF AND ONLY IF your charging circuit detects the battery charge status and adapt to it (i.e.: entering a trickle charging mode when battery is almost full). If the charger is not "intelligent", then it is not advisable to charge at more than C/10.
Most current models of cell phones, laptops and PDAs do charge at more than C/10 in order to achieve recharging times of 2 hours or so, but "smart" chargers and batteries are required. Hint: see how many contacts a battery pack has, "smart" battery packs may even have a microprocessor on-board... so it is usual for them to have at least positive, negative and one or more extra contacts to sense the battery status or to communicate with such on-board battery controller.
Keep in mind that, at least in Woodstocks, the charging circuit is absolutely not intelligent, but since it is a half wave rectifier, the real current applied is about 45% of the DC value... This may explain the C/4 vs. C/10 issue in that case.
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