Rychu, when my original batteries failed, I emailed Ed at Ambient. At that stage rechargeable alkaline batteries was out of stock for some period.
This is the current wording when ordering batteries.
This is the current wording when ordering batteries.
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Note: The weather station uses alkaline batteries because of their wide temperature range. However, any AA battery will work in the unit, including non-rechargeable batteries.
If alkaline batteries are unavailable, we recommend non-rechargeable Energizer e2 Lithium batteries. They operate between -40 °F and 140 °F (-40 to 60 °C). They will not damage the weather station or the batteries because of the low charging current.
Using Ni-Mh rechargables are fine but expect a very limited temperature operating range.