The iPhone has a battery that gets most people through the day, but it oftentimes doesn’t last much longer than that. The nearest wall outlet isn’t always convenient, so a healthy market for external batteries has sprung up. Dexim’s P-Flip is a combination battery and desk stand that roughly triples the time you can spend away from a power source.

The back view of the P-Flip, when closed, really looks like a travel alarm clock.

Here’s what the P-Flip looks like just before you insert an iPhone. Note, again, the charge indicator LEDs showing a full charge.

The front of the closed P-Flip has three blue charge indicator LEDs (illuminated here).

The dark grey metallic plastic P-Flip looks a lot like a travel alarm clock. It has three charge indicator LEDs along the back edge, with a mini-USB charging port on the right side and a charge test button on the left. The test button works much like its counterparts on PowerBook and MacBook batteries have for years; simply press it and the LEDs indicate the current state of charge of the P-Flip’s internal battery.

This small button, on the left side if you’re looking at the open P-Flip, triggers a charge level test like the buttons on Apple’s notebook batteries.

The right side of the P-Flip has its mini-USB port, through which you can charge your iPhone, sync it, or simply charge the P-Flip, or any combination of the three.

With a capacity of 2000 mAh, that internal Li-Ion polymer battery should be able to provide just under one and one-half full charges of the iPhone’s 1400 mAh internal battery, or roughly two complete charges of the iPhone’s battery from the “20% remaining” warning. That’s probably enough to keep the average iPhone user going for at least three full days away from any other source of power, assuming a full charge on day one. The P-Flip’s capacity falls around the middle of the spectrum in the market—Mophie’s Juice Pack Air battery/case combo and the i.Tech SolarCharger 906 have less capacity than the P-Flip, but there are several products out there with equal or (much) greater capacity at (much) lower cost.

Both of the aforementioned external batteries have their own drawbacks, but the P-Flip isn’t perfect either. Its ultimately fatal flaw is a design that completely prevents using a case of any kind with your iPhone. The form-fitting support, presumably intended to prevent excessive pressure on the dock connector while using the P-Flip as a desk stand, is too form-fitting for a case. Removing your phone from a case that otherwise allows charging via a normal USB cable is just too much trouble.

Sadly, the P-Flip is totally incompatible with any cases, which makes it pretty useless to me.

Furthermore, the P-Flip isn’t a great desk stand. It holds the iPhone too close to the vertical, making it difficult to use the phone while it’s standing up. It’s less stable than either the Keynamics Element or PED3 stands, and it’s useless in landscape mode, despite the photos on Dexim’s Web site. (Oddly enough, using the stand in landscape mode as depicted will cause lots of accidental actuations of the charge indicator button.)

To get this photo, I had to get the camera down to desk level, which is some 18 inches below my normal eye level. It’s simply not comfortable to use the iPhone at this angle.

It’s difficult to tell just from this photo, but unless you sit almost eye level with your desk surface, the P-Flip holds the iPhone nearly vertical, too much so to be comfortable as a stand.

As with the Juice Pack Air, the P-Flip uses a mini-USB connector and allows syncing the iPhone via the included cable while the phone is on the stand. This is nice, because it allows most people to carry just one cable. Folks who carry around multiple Apple devices still need to carry a second cable, and for these people, a dock connector pass-through would be much more convenient, even if it added $5 to the price.

Finally, there’s the question of value. The $55 price is quite simply out of line. When you can buy a much better desk stand for $30 and a higher-capacity 2200 mAh battery pack for another $15 (disclaimer: I haven’t used that particular battery pack, so I don’t know whether its dock connector is long enough to be fully compatible with most cases or not, but the point stands) and still have $10 left over for a four-pack of good stout, I’m just not seeing a reason to spend that money on an average battery pack that doesn’t play nice with cases.

Copyright © 2010 Chris Lawson. Reviewing in ATPM is open to anyone. If you’re interested, write to us at reviews@atpm.com.