ladyada has updated her MintyBoost battery pack and charger with a higher output step up converter.
She writes, “The upgrade was necessary as the latest Apple products really need a lot of current to charge and hopefully they will work better now!” The MintyBoost uses 2 AA batteries and an Altoids tin for a case.
I’ve built two V1.0 kits and used them to charge a cell phone and my iPod. The MintyBoost is great because it’s small and will give you the additional power to keep your phone or iPod running when you need it.
You can buy the kit and get technical information at ladyada.net