I also use a BT temp sensor in my car for help tracking car presence and cabin temp.
I use a govee h5075 and some basic aaa rechargeables. I keep it out of direct sunlight, and it has lasted many months before needing batteries swapped, and several years over all. I have a handful of these devices, for around the house and in fridges/freezers.
My cabin temps have generally ranged from ~110 to ~20 F.
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