The cost of a new battery is $13.99 on ebay, and this is your best choice, once you rule out bad USB connector, cable or charger. Buy from a vendor who supplies the plastic pry tool for opening the case of the reader. I fixed an ancient Kindle DX Graphite over the holidays, so have no fears. Swapping out the battery on an iPhone is complicated. Amazon's products are a lot more maintainable (because they tend to be less reliable).