I use these batteries in my "Eleaf iJust" evaporator and can not complain at all. In about 3 hours they are each charged and are then usually up to one and a half days in continuous use. They provide a constant stream of energy for my steamer Rescue the always runs the highest volts / watt rating. And now for nearly 3.5 months without any faults or performance degradation. What more do you want?