Today, I’m going to talk about the IMP500A external charger for the iPhone 3G, 3GS and 2nd generation iPod Touch. When I mention iPhone throughout this review, I’m also referring to all three devices mentioned above.

This thing is a beast. 5000mAh of pure charging goodness wrapped up in a well-constructed high-impact plastic case.

Sold by, the IMP500A is a thing of beauty. The company claims that the unit is built by an OEM (original equipment manufacturer) to Apple, and though I can’t confirm it, I can well believe it. Weighing in at about five ounces, and with physical dimensions of 3.9 x 2.2 x 0.6 inches, the IMP500A fits easily into an extra pants pocket. You can purchase it for under $60, which ain’t bad, folks.

The IMP500A arrived at my door in an attractive package that required a little wrestling and a razor blade to get into, but that seems pretty standard for packaging these days. Once I rescued the IMP500A from its plastic cocoon, I was able to take stock of what I had.

In The Package

Aside from the charging unit itself, the IMP500A comes with an instruction booklet, a wall charger, a retractable USB cord (charging cord) and an adapter for the docking port of your iPhone. All pieces are of quality construction and attractively designed.

Included Items

The charging unit has a standard size USB port on the upper end into which you plug the USB end of the charging cord when you want to charge your iPhone with the IMP500A. You can vary the length of the charging cord simply by pulling on both ends and stopping when you have enough length for your use. You then pull lightly on both ends of the cord to retract it. Plug the dock adapter into the other end of the charging cord and turn the charger on. The power button is located on the upper left of the charging unit. Beside the power button is a row of red LEDs that indicates the level of charge remaining on the unit. There are three LEDs to indicate strength, and one LED that lights up when the IMP500A is on and charging your iPhone.

USB Port Open

Charging Cord

When it is time to recharge the IMP500A itself, there is a jack on the upper right side that accepts the smaller plug on one end of the charging cord. If you have the dock adapter on, remove it to gain access to this plug. Put the plug in and attach the USB end of the charging cord into the USB port on the wall charger. Don’t make me explain how to plug it in! The three power level LEDS on the charging unit will flash in succession until fully charged. A full charge from empty takes a couple of hours.


Now for the meat and potatoes of the review:

The IMP500A, fully charged, was able to recharge my iPhone 3G almost four complete times. Here is the breakdown:

1st charge: From 32% to 100% while using the MLB At Bat app on the iPhone.

2nd charge: From 17% to 100% while using the iPhone to browse (fairly heavy use here).

3rd charge: From 12% to 100% with no iPhone use.

4th charge: From 7% to 92% with no iPhone use. At this point the IMP500A died and had to be recharged.

Now, I normally don’t recharge my iPhone (I have a 3GS now, so nyah!) completely with the IMP500A, but it is handy for charging it enough until I can get the iPhone to my computer to charge later on.

LEDs and Power Button


The imaxpower IMP500A is a solidly built, reliable and good-looking external charger for your iPhone 3G/3GS and 2nd generation iPod Touch. Though not as elegant as a case charger, 5000mAh of recharging power is a good thing to have on tap during those heavy-use days. Highly recommended!