January 26, 2006 - Whenever a PSP vs. DS debate begins, the one argument you can always expect to hear against the PSP is battery life. Somewhat unjustifiably, the rumors and speculation about the PSP having a tiny battery that began before launch still seem to be associated with the device. In truth, the PSP's internal 1800 mAh lithium-ion battery does a pretty good job powering such a big screen, but even the biggest PSP fans do have to admit a little more juice could come in handy.
Enter the Tank-1002 battery pack. The Tank unit is a 4400 mAh Lithium-polymer battery pack that attaches securely to the back of the PSP. Contoured appropriately and molded in black plastic, the Tank unit has a relatively minimal impact upon the PSP's overall form factor. It weighs an additional 156 grams, which isn't really enough to make a dramatic difference, and it increases the PSP's thickness by about a half an inch.

The increased thickness has both positive and negatives. Most people find the PSP more comfortable to hold with the Tank-1002 attached, but the downside is that the PSP won't fit in most slip/carrying cases with the Tank included. Fortunately, the Tank-1002 is bundled with a zippered neoprene carrying case that will hold the united PSP and Tank in a warm and caring embrace.
Another cute feature of the Tank-1002 is a kick-stand style foot that pops out of the back side of the unit to prop the PSP up at a comfortable viewing angle. The angle produced is perfect for on-desk applications, and works pretty well on an airplane tray table as well.

Battery performance is the key feature for the Tank-1002, and in our tests it lived up to its claims of expanding the PSP's play time by around 8 hours. That's a pretty significant boost compared to the natural PSP's roughly 2.5-3 hours, and is especially important in terms of UMD playback, which really tends to use up power because the disk is constantly in motion.
The unit also has good power-management features. The Tank-1002 completely drains its own battery before switching to the PSP's internal supply, and it makes the transition without any interruption in play. There is also a switch to turn off the Tank, if one was so inclined. The Tank and PSP together charge from empty to full in about 4 hours.

The Tank charges by means of the PSP's AC adaptor, and connects via a plug on the center-top part of the pack. Playing the PSP with the Tank and AC power connected feels different because of the non-traditional location of the AC power plug, but it's not a huge deal. The only major downsides of the Tank-1002 are the fact that it must be removed to change UMDs, and the fact that it also occupies the two mounting holes that most screen-protector shells must use. Removing the Tank is as easy as gently pulling it backwards, so it's not that much of a hassle to change games, but you are pretty much committed to the included carrying case for PSP protection once you go the Tank route.

Overall, the Tank-1002 does its job quite well. For a relatively minimal impact upon the overall PSP form factor, the Tank packs a good amount of extra battery power. An extra 8 hours will get you through some long flights and hardcore road tripping. The MSRP on the device is $59.99, which makes it the value leader among currently available competing products in a battery life to cost ratio analysis. Carry a Tank in your pocket and you can laugh at all those DS kids when they talk to you about the PSP only lasting 2 hours. They're going to go blind from those tiny screens anyway, so bide your time and plan a fitting revenge.

Review link http://gear.ign.com/articles/683/683895p1.html