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Old 07-14-2006, 10:10 AM   #56 (permalink)
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Default Does the BB charger step down when full?

So the Battery University article talks about the danger of overcharging, from the perspective of heat:

Limit the time at which the battery stays at 4.20/cell. Prolonged high voltage promotes corrosion, especially at elevated temperatures. (Spinel is less sensitive to high voltage than cobalt-based systems).
Does the BB cut the voltage when it senses the battery is full, thereby avoiding this problem, i.e. if you charge it overnight? As in this 'standard' feature, not sure if BB has it:

Much attention is focused to avoid over-charging and over-discharging. Commercial lithium ion packs contain a protection circuits that limit the charge voltage to 4.30V/cell, 0.10 volts higher than the voltage threshold of the charger. Temperature sensing disconnects the charge if the cell temperature approaches 90xxx176;C (194xxx176;F), and a mechanical pressure switch on many cells permanently interrupt the current path if a safe pressure threshold is exceeded. Exceptions are made on some spinel (manganese) packs containing one or two small cells.
My battery typically only goes down a bar or so at the end of the day but I plug it in every night to top off, so it's charging for at least 6 hours.