So, as you shop around and research the electric bike conversion kit market, keep in mind the chemistry type of the batteries you are comparing, make sure you have some clear comparison criteria in your mind regarding how much power a given battery will hold given it's size, weight, and price, and check out our additional battery pack and lithium upgrade options at http://www.electric-bike-kit.com/ if you're pondering what your future battery pack purchase options will be. 
Also, if you haven't already, please show your support of electric transportation by becoming a Facebook fan of the Hill Topper, because each individual making conscious decisions about energy consumption is the best option we have for creating a sustainable society without sacrificing our standards. You can also post your thoughts and comments on our Blog