Good choice

#RankBoosterReview ii. #Sponsored iii. #Keenstone 9V 800mAh Rechargeable Li-ion Battery with 3-Slot Charger for TENS Smoke Detector Multimeter Alarm System etc

https://www.amazon.com/Keenstone-Rechargeable-Detector-Multimeter-System%EF%BC%883-Pack%EF%BC%89/dp/B078JMHHF8

Keenstone 9V Li-ion battery is non-toxic, without memory effect and environmental friendly. Cycles life can be up to 500 times.  9V 800mAh rechargeable li-ion battery with 3 packs, higher capacity than ordinary 9V battery, more affordable and environment friendly. These batteries provide the correct amount of current and voltage, seem to last longer than the Duracells. And I never have to worry about running out of batteries.