The manufacturers and distributors have to publish an official temperature range that will minimize their liability, and satisfy the needs of all, or most of, their customers. Funny how the round number "0C" was chosen. The electrolyte is not water and thus this temperature has no special significance. In reality both "charge" and "discharge" are fuzzy concepts. How much current? Sellers of LiFePO4 batteries used for starting engines of ATVs and such recommend not starting (a high-current discharge) below freezing. In this world where people want ever-faster charging (15 minutes, 30 seconds...), it's safer to say "charge above 0C". But various sources say that one can charge at freezing temperatures - slowly. For that matter, at temperatures only slightly above freezing, too, it's probably best to charge slowly. Personally, I charge all my batteries slowly if I can, at all temperatures. If I have all night, why force all the charge in 2 hours? Any charge rate that makes the batteries hot to touch is damaging in the long run.. I always use my BC700 charger for NiMH cells (awesome device!) at its lowest charge current (200 mA). I charge the batteries I use in my glider (SLA, 4AH to 12AH capacities) at half an amp or less.