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Charging my iPod



 To answer your questions: 

>> Doesn't the iPod use a lithium polymer battery[1]? 

The one that came out of my iPod says it is a Lithium-Ion battery, as is the 
one that replaced it [ 
ipodjuice.com<http://www.ipodjuice.com/AB4F1D8928C84BDB946D9070006DB952.asp?cat_id=DB0F4AD92C33496280F12D141343615B&amp;pcs_key=4E5940238DB84199B846D11EAF1075A6&amp;retpage=%2Fipodjuice%2FVirtualWeb%2F59CA69DE181F46B69521D30B707A4ABB%2Easp&amp;nm=bhBAT3G1100&amp;spath=Home+%3E+3rd+Generation+iPod&amp;path=Home+%3E+3rd+Generation+iPod> 
]. 
>> Do the instructions say don't use USB in general, or specifically for the 
first few charge cycles? 

"While it's not mandatory, we commend charging your new battery the first 
few times directly to a power outlet (instead of trickle-charging via 
computer) for at least four hours." 

>> Without knowing the battery chemistry and capacity, it's hard to say 
whether the power supply is adequate for a first charge. 

The battery is rated for 1100 mAh... that was my bad. I should have read 
more into it before I asked, but thanks for the helpful pointers in the 
right directions. I've decided I'm going to attempt it... after I find the 
OEM wall charger's electrical output specifications. Thanks again for the 
help! 


On Nov 24, 2007 2:22 AM, Tom Metro <[hidden email]> wrote: 

> Jon Hermansen wrote: 
> > Since I've just installed this battery, I want to make sure that I 
> charge it 
> > correctly and fully the first few times, i.e. not "trickle" charging it. 
> The 
> > instructions that came with the battery specifically indicate that I 
> should 
> > NOT charge it over something like USB (or FireWire?) 
> 
> Doesn't the iPod use a lithium polymer battery[1]? 
> 
> According to: 
> http://www.batteryuniversity.com/partone-12.htm
> 
>   Lithium-ion...does not need priming as nickel-based batteries do. The 
>   1st charge is no different to the 5th or the 50th charge. Stickers 
>   instructing to charge the battery for 8 hours or more for the first 
>   time may be a leftover from the nickel battery days. 
> 
> Do the instructions say don't use USB in general, or specifically for 
> the first few charge cycles? 
> 
> 1. http://en.wikipedia.org/wiki/Lithium-ion_polymer_battery
> 
> 
> > GRIFFIN AC POWER SUPPLY 
> > OUTPUT: 5.0V   500mA 
> > 
> > Can anyone tell me if this is a more high powered charger, or if I use 
> it 
> > will the results be the same as if I charged it over USB? 
> 
> If I remember correctly, USB supports both high and low current devices, 
> with the high current being supplied by PCs and powered hubs. I believe 
> that the high current limit is 500 mA. So this charger matches that. 
> 
> The warning might be because it's simpler to say don't use USB than 
> trying an explain that it needs to be a port supporting high current 
> devices. Or, if the iPod has a separate charger jack, perhaps it does 
> support charging at higher currents. 
> 
> If it was a NiCd battery, 500 mA would be pretty decent, as you 
> typically charge at .1C where C is the batteries capacity (that's the 
> slow, "overnight" rate, but usually faster than the "trickle" rate). So 
> that'd be a 5000 mA/hour or 5 Ah battery pack, which I'd guess is bigger 
> than what the iPod uses. Though a quick charger or one designed for NiMH 
> will use a faster rate. 
> 
> The above page also said: 
>   Smaller batteries used for cell phones can be charged at 1C... 
> 
> and if that's applicable here, the 500 mA supply probably is too small. 
> But the page also says: 
> 
>  Increasing the charge current does not shorten the charge time by much. 
> 
> Without knowing the battery chemistry and capacity, it's hard to say 
> whether the power supply is adequate for a first charge. 
> 
>  -Tom 
> 
> -- 
> Tom Metro 
> Venture Logic, Newton, MA, USA 
> "Enterprise solutions through open source." 
> Professional Profile: http://tmetro.venturelogic.com/
> 


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