Anyone Build Their Own Battery Pack for iPod?

My daughter just bought a 30GB video iPod, but the run time for videos is only about 2 hours (if you're lucky). Was looking for an accessory battery pack to extend the run time but (yikes!) the prices they want are crazy! Belkin makes what appears to be a decent one, using 4 x AA batteries, but the price is $49-$59.

Anyone know why I couldn't (shouldn't) buy a 4xAA battery holder ($.99, 6V output with 9V connector attachment already built-in), and a couple 9V connectors ($.50 each)? I'm thinking about cutting off the dock/charging connector from a 12V iPod car charger and splicing a couple 9V connectors, so you could use the iPod connector with either the car charger, or the battery pack.

Belcan claims 3-4 times the runtime, when using 4xAA alkalines, so if I use 4xAA 2500 maH rechargeables, what additional runtime might I expect?

Thanks for any input...

Most likely, the expensive battery packs come with current and/or voltage regulation. A possible spike or drop in power could negatively affect the IPOD? You would have to double check input Current..

sorry, dont have one

-tom

I was at CompUSA and they have replacement batteries for the different Ipods for about $49 for a battery and the tools. The battery packs are a little smaller than a Compact Flash memory card. I was thinking that if there was room inside a cellphone battery might be made to fit as it probably has more capacity than the little packs.

My Ipod wall wart is rated for 12 volt .67 amp output Firewire's voltage range is stated at 8-30 volts at the computer end and it looks like 12 might be the almost "standard". It doesn't look like the input voltage is much of an issue unless it is too low.

In otherwords, it doesn't look like 4 NIMH cells will trouble the machine. But that is my guess on how I think it should behave.

I just purchased and built this kit. Works great. There was an article in Popular Science about it.

I'm thinking that the commercial battery packs probably have some sort of regulation built in. Maybe that's why they're so expensive. The one at tiktoc 22's link also uses a regulated IC. Sounds like there may be more to it then just plugging in a cheap battery pack to the right connector.

bucken said:

The one at tiktoc 22's link also uses a regulated IC.

Click to expand...

Correct. It's simply a small 5 volt regulated chip. I'm not sure what the input voltage is rated at on this chip, but I bet it would also work on a 12 volt system. I am considering mounting a USB port in my car for charging anything that can be charged via USB.

tiktok 22,
Are you absolutely sure the output is only 5V? What are you using yours on, and how much additional time have you experienced?
Thanks,

bucken said:

tiktok 22,
Are you absolutely sure the output is only 5V? What are you using yours on, and how much additional time have you experienced?
Thanks,

Click to expand...

Yes, the output voltage is 5 volts. Here is a link that explains a litlte more. I've charged an Ipod twice(not completely dead) on a fresh 9 volt battery, but don't know what happens if the voltage of the battery drops to low. I may be able to use it more, but don't want to damage anything due to voltage issues although I *don't think* anything bad will happen.