[LChoy]

Fastest to Slowest:
1. Griffin's PowerBlock iPad charger
2. iPad standard charger
3. iPhone standard power adaptor
4. USB to MacBook

We took the four most common ways to charge an iPad: The iPad's standard 10W charger, Griffin's PowerBlock iPad charger, the iPhone's standard power adapter, and via a MacBook Pro's USB port. We timed how long it took to bring the battery up to 80%, which is the standard baseline for a "quick" charge. That last 20% goes very slowly to preserve battery life, so doing total time wouldn't give a fair indication of the charging method.

The PowerBlock proved to be very slightly faster than the standard iPad 10W power adapter, getting us to 80% after just 2 hours and 30 minutes of charging, but it's sharply downhill (or rather, uphill) from there. While that doesn't mean you should toss your iPad adapter and buy a Griffin straight away, it does mean that if you need a spare or a replacement charger, you could skip the Apple-branded one, and hunt down a PowerBlock, preferably on sale for less than the $30 list price.

The poor performance of the MacBook Pro USB jack teaches us another thing: Direct juicing is better, if given a choice.

One last thing about iPad battery management: It's worth taking a peek at Apple's recommendations for optimal iPad battery lifespan. Of note, you ought to take your iPad through a full recharge cycle once a month. That means running it down completely, then charging it to 100 percent.

http://gizmodo.com/5535631/the-faste...charge-an-ipad