Review on 🔥 Kidde Hardwired Smoke & Carbon Monoxide Detector with Voice Alert & Battery Backup – Interconnect Combination Alarm by James Cross

I'm replacing the old unit with a new one exactly the same. On the old device, the battery exploded and burned a hole in the battery compartment, the photo shows black soot and a hole. Not sure if it was a bad 9 volt battery (from BJ) or something wrong with the detector itself as it is hardwired to 110 volts and only uses the battery as a backup. Like something happened and it put the energy back into the battery and it exploded. Luckily no fire. Very strange. See photos.