Pros: A nicely designed combination of silicone rubber case and iPod battery pack, boasting around four times the bare iPod’s battery capacity, and adding more than 9 hours of video playback or around 60 hours of audio playback to a discharged iPod. Case is substantially protective. Available in white or black colors, each with matching wall charger.
Cons: No screen protection in case. Unlike prior battery packs, i603 battery is fifth-generation, 30GB iPod-specific and won’t necessarily fit any other iPod model (current or future) properly.

Like other iLuv products, the i603 battery and silicone case pack is sold in white (i603WHT) and black (i603BLK) versions, which other than coloration are identical in features. Each box contains a lithium polymer battery promising up to 42 hours of added music play time for a 30GB, fifth-generation iPod; a separate version (i604) promises 55 hours of added run time for the 60GB iPod. The battery is covered in plastic and housed inside a silicone rubber case that covers the entire iPod save its Click Wheel; a prominent chrome bottom extends the iPod’s bottom and includes a pass-through Dock Connector port for charging. You get a wall charger with each i603 unit, but must supply your own iPod cable to recharge the battery.
It’s been a long time since we’ve tested a new external battery pack for iPods, and the reason’s somewhat surprising: despite the power drain caused by video playback, companies haven’t rushed to release new batteries – Battery Technology Incorporated, Belkin, and Nyko have just re-packaged old ones for new iPods.
So it was with some excitement that we received new battery packs called i603WHT and i603BLK ($70) from iLuv – the first really interesting new designs we’ve seen in a while. The i603s are specific to a single iPod model – the fifth-generation 30GB iPod – and don’t properly fit thicker 60GB iPods. (Updated November 1, 2006: We have now tested the i604 as well – as reviewed in our 2007 iPod Buyers’ Guide – and found that it surpassed its promised 55 hour run time by a similarly impressive magin.)
The basic idea behind i603 is that most iPod battery packs don’t look good, so iLuv has gone in a different direction, effectively hiding its lithium polymer pack inside of a unique housing. Each i603 looks from the outside like a silicone rubber case with a chrome bottom, with smoky black silicone for the BLK version, and frosted clear silicone for the WHT. A bit less than an iPod’s worth of thickness is added to your 30GB iPod, along with a half inch of extra height. You pop your iPod inside the case, resting its back aganst a glossy plastic battery housing, and watch your iPod’s battery double.

iLuv promises up to 42 hours of added music play time for the 30GB iPod, or around three times more battery life than what the iPod can deliver alone.
In our tests, the i603 actually surpassed this, delivering around 60 hours of music time with a fully discharged iPod battery – more than four times the iPod’s normal peak. Similarly, for video playback, the i603 did really well, playing back a collection of TV shows and movies for a total of 9 hours and 22 minutes, or four and a third times that iPod’s typical 2 hour, 10 minute video runtime. Again, these numbers reflect performance with a fully discharged iPod battery; if your iPod’s charged, you can see even greater run times.

Charging the i603 is fairly easy, but time consuming. You can connect any Dock Connector cable to its bottom, then to your computer or the included, color-matched wall charger, and let the charging process commence with or without an iPod attached; both devices can charge at the same time. There’s a single red light on the unit’s left side that indicates charging is not yet complete, changing to yellow when the process is done; there is no way to tell how charged or empty the battery is at any particular time, unlike many but not all of the batteries we’ve previously tested. Since charging takes a number of hours, you’ll need to let it sit around until the light changes.

Other than more detailed power indicators, our only cosmetic gripes with i603 are small ones: the included case doesn’t include screen protection in any form, stick-on, hard, or otherwise. As a case, it would otherwise score perfectly on protectiveness – there’s a hole for your headphones, but coverage for everything else, front and back.