Although we do not use the SM Mini frequently, we have Audiomoths in use wich uses the same batteries.

Batteries: We use Ansmann type 2850 NiMh rechargeable batteries with 2650 mAh. They work fine and had reasonable pricing. As well I have been using Panasonic Eneloop pro BK-3hCDE NiMH Batteries. They are great as well, in my experience.

Runtime: The website of Wildlife Acoustics states: 4 AA Alkaline: 210 hours (typical at 24kHz mono) --> The Alkalines have a bigger capacity / longer runtime, but that would easily be above your stated requirements, if I'm not mistaken.

Hope this helps.

Although we do not use the SM Mini frequently, we have Audiomoths in use which uses the same batteries.

Batteries: We use Ansmann type 2850 NiMh rechargeable batteries with 2650 mAh. They work fine and had reasonable pricing. As well I have been using Panasonic Eneloop pro BK-3hCDE NiMH Batteries. They are great as well, in my experience.

Runtime: The website of Wildlife Acoustics states: 4 AA Alkaline: 210 hours (typical at 24kHz mono) --> The Alkalines have a bigger capacity / longer runtime, but that would easily be above your stated requirements, if I'm not mistaken.

Hope this helps.