Accessories Question about battery charging

[incy1020]

Hi:
This may be a dumb question. If so, sorry
I have purchased an extra battery. I will likely not use it often, but it's nice to have just in case.
If I keep this battery in my purse, and do not use it, how often should I charge it? Or will it stay charged?
Thanks!

 

[Grut]

it should stay charged till use. I keep a fully charged extra battery on hand for my digital camera, so the cell phone battery should keep the charge.

 

[incy1020]

Thanks so much for the reply!!

 

[mckooter]

more specifically, (from wikipedia, i looked up because i was fairly certain but i wasnt sure of the exact numbers)

Self-discharge rate of approximately 5-10% per month, compared to over 30% per month in common nickel metal hydride batteries, approximately 1.25% per month for Low Self-Discharge NiMH batteries and 10% per month in nickel-cadmium batteries.[31] According to one manufacturer, lithium-ion cells (and, accordingly, "dumb" lithium-ion batteries) do not have any self-discharge in the usual meaning of this word.[22] What looks like a self-discharge in these batteries is a permanent loss of capacity (see Disadvantages). On the other hand, "smart" lithium-ion batteries do self-discharge, due to the drain of the built-in voltage monitoring circuit.

[ via Lithium-ion battery - Wikipedia, the free encyclopedia ]

im not sure how "smart" these batteries are, and due to their size I might even say they arent at all (meaning no circuitry, no voltage monitor in battery) maybe someone else can confirm the details of our specific battery

 

[Rred]

These batteries are dumb, they have no on-board electronics or intelligence but they don't need any. The CHARGER, or the phone itself, is the place where the charge control circuit needs to be. (If you charge the battery in the phone, either one can control charging. if you have a dock that charges a spare battery, the dock needs brains itself.)

Since all the batteries will be lithium type, you have no choice in that matter. Something, probably the phone, is controlling the charge. Lithium batteries basically don't self-discharge the way NiMh and NiCad types do, so swapping the battery and charging it up once a month should be just fine. Even two months, it will still be subtantially "full".

But there's a gotcha. Even if you don't use the spare battery at all, you can expect it to fail without warning by the 4th year. Lithium batteries typically give 2 years of "full" use, two more at dimished (half) capacity, and by the fourth year they often die without warning. So, use it or lose it anyway.

Depending on which manufacturer you believe, a lithium battery is good for 500-1000 full charge cycles and that's all. Two years of "full day before recharge" and if it still holds a full charge--it is time to replace anyway.

Anyone figure out how to make the phone stop waking them up at night saying "I'm fully charged, please unplug me now!" ??

 

[kspec1212]

Anyone figure out how to make the phone stop waking them up at night saying "I'm fully charged, please unplug me now!" ??

Yeah - put the phone on silent!!!

 

[Rred]

Put *this* on silent.

Which is, somewhat more politely, what I told the AT&T ditz that made that suggestion.

If I wanted to turn off my phone, I'd just cancel the service.