Perhaps Hubby can get up with some canned "air" of the sort used for dusting electronics and spritz the detectors against the possibility of dust motes setting off your detectors. Also, if they have over ten years age, they can fail and require replacing as a lot anyway. This is not something which would have been triggered by your recharge sequence. Gosh, if recharging tripped them, then how about your cell phones in recharge mode or your landline phones [if you have them] which are wireless and sit in recharging cradles......

Oughta check out those detectors.....

Yup.