On the 14th of January I replaced the batteries on three of my second generation motion sensors as they were either 1% or dead. Today I had to replace them again as one was dead and the other two were on 1%. I know this cant be normal. The batteries were brand new Duracells on the 14th and brand new Panasonics today. Surely even in the cold weather - my flat is probably around 5 centigrade while I am away - this cant be right? Ive done a rest of the sensors so will see what happens now. If they keep doing this I will assume it is an age thing and start looking at replacing them with xiaomis.