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I just bought a new battery for my Fujitsu-Siemens PA-1510. The battery label claimed that, in order to have a long living battery it is important to charge it at least 10 hours before the first use.

So I put it in my Notebook and connected the power. After 1 hour, the charging indicator stopped flashing, trying to convince me that the battery is fully charged. But I wanna charge it 10 hours. Is the battery still charging, even so the indicator switched from "red blinking" to "green constant". Do I have a chance at all to charge it 10 hours?

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Assuming it's a lithium-ion battery pack, charging for a specified length of time (such as 10 hours) permits calibrating the battery gauge so it knows where the charge tops out. If you stop charging early, the battery may be only partially charged, but the battery gauge (software or firmware) will think that is the point where the charging has topped out; thus it will be miscalibrated and will erroneously show the battery as fully charged. So follow the manufacturer's advice for the first charge, as well as for recharges for the same length of time to recalibrate from time to time as the battery ages.

There are some old myths floating around about battery "memory" and how overcharging a battery is bad for it. That only applies to nickel-cadmium (NiCd) batteries, though, which almost no one uses anymore. For lithium batteries, the opposite is true: it's bad to let them drain all the way to an empty charge. The usual recommendation when storing a Li-ion battery unused for months at a time is actually to leave it half-charged.

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thx L2G, yes it is a lithium-ion battery. So you think my battery is still charging even with the led indicator claiming the opposite? – Max Dec 7 '11 at 17:52
If the battery has not yet been charged for the full 10 hours, then yes. It never hurts to charge the battery past the point where the gauge says it's fully charged; in fact, you should do so every month or so to ensure the gauge is calibrated properly. – L2G Dec 7 '11 at 19:42
@L2G it hurts the battery if it is fully discharged, I read. So charging even after full charge can be considered as an alternate method to calibrate? – Spandan Chatterjee Dec 24 '12 at 18:15

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