i bought it at the end of November from Kalamazoovaporshop and it's been working stupendously until last sunday. i went out of town and had a long drive home and wound up killing the battery for the first time. it took around 14 hours off the charger to finally give up. prior to that, i had yet to drain the battery, even vaping all day at work. since then, with no change in habits o anything else, the battery's barely lasting 8 hours on a full charge. is it on it's way out?