I want to learn the GFD lead acid batteries used in NPP. Have Exide and Deka ever supplied for NPP, or who are the main suppliers in this field? We know VRLA betteried dominate the market now, but have this type ever been use in NPP? As for UPS, do bettery suppliers provide UPS together with batteris, and who are the leader companies in UPS market worldwide? look forword your help, thanks!