http://www.amazon.com/gp/product/B000CGG8LW/sr=8-10/qid=1199538263/ref=pd_cp_e_1?ie=UTF8&qid=1199538263&sr=8-10&pf_rd_p=250314601&pf_rd_s=center-41&pf_rd_t=201&pf_rd_i=B000O2YOII&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=08QRZJA46ETMCX3TEC8HAmazon.com Product Description
The Macally IP-A481 external lithium-ion battery adds hours of playtime to your iPod wherever you go. Ideal for long flights, outdoor activities, serious road trips, and a ton of other applications, the high-capacity battery provides an extra six to eight hours of power-- enough to enjoy another 100 or so songs. Connection is simple, with a port for direct connection to the iPod shuffle and a USB port for other iPod models (use the 30-pin USB sync cable that came with your iPod). And once the battery runs down, simply connect it to your computer's USB port for quick recharging. The IP-A481, which includes a built-in battery tester button and a battery-level LED indicator, works with the following iPods: 3G, 4G, 5G, iPod Photo, iPod with video, nano 1G, nano 2G, mini, and shuffle 1G.
The battery measures 2.4 by 0.6 by 4 inches (W x H x D), weighs 11.3 ounces, and carries a one- year warranty.
What's in the Box
IP-A481 battery, USB-A to USB-mini B cable, user's manual.
Product Description
Recommended for iPod shuffle, iPod 4G, iPod Photo, iPod with color display, iPod Mini, iPod nano & iPod with video / Add hours of play time to iPod device Recharge from computer's USB port convenietly with included cable Built-in battery tester button with battery level L.E.D. indicator Includes 1 USB-A to USB-mini B cable Output Voltage - DC 5V Output Current - 1000mA max. Dimension - Height 3.9 x Width 2.4 x Depth 0.6 inch Weight - 11.3 ounces
The same unit is available for less here:
http://www.newegg.com/product/product.asp?item=N82E16855998033
$34.99
That unit is what I have used and it works great...