I'd like to revive this thread as I am currently in the process of trying to sell Li-ion batteries for the first time. Not a whole lot, but none of the yards near me take them. cashforcomputerscrap, (by the way is that ewasted?) is looking like the best price. Since I am on the mainland and can ship ground, can they just go in a flat rate box? And how many laptop batteries can I expect to fit in a large flat rate?