Bought a set of 2 of these Panasonic CGR18650 3.7v batteries and I have been using them for about three weeks. Had a fully charged one and one in my vamo, got a low v signal and swapped batteries, putting the dead battery on the charger. Well when it was charged I put it back in my vamo and it will not fire up. It will fire up however with the other battery. And the charger gives me a fully charged signal. Any ideas?