Yes, that’s right. they’re discontinuing the item and will soon be impossible to find on store shelves once all are sold. If you don’t know what it does, it provides a little more battery life than the standard battery for the Fat, but when used on the Slim, the battery life jumps from roughly 4-6 hours to 7-10 hours (both figures assuming that a movie or game is being played). The package claims 12 hours of battery life. The disadvantage to using this on the PSP is that the pack will jut out a little bit when used on the PSP with the faceplates that come with the package.

This is what SCEA’s Al de Leon had to say:

          "Yes, we are discontinuing this product as we look for other opportunities to service the consumer."

Well, it’s certainly a shame... If you still have the intentions of picking one up in stores, and if you can find it, it retails for approximately $40.

Source