I’m getting tired of buying all the different kinds of button cells needed for different sensors.
Are there any good sensors which use AAA or any other kind of rechargeable batteries?
I use the Aeotec Door/Window 6 sensors. They are rechargeable. The battery is not replaceable, however. Recharge via USB.
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How have you found the battery life of these? Stated life is 1 year on windows and 9 months on doors so curious to know how accurate that is…
In general you should not use rechargeable batteries with sensors unless it is one built into the device. That is, you should not simply swap out rechargeable AAA or AA batteries for nonrechargeable ones like you might do with, say, video game controllers.
The reason is the rechargeables have a different discharge curve which will cause two problems.
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the battery life reporting from the device will be wildly inaccurate. It might report 50% in the morning and be dead in the afternoon. Not because it suddenly used up a lot of charge but because the 50% report was wrong.
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you may get inaccurate sensor reports because of fluctuating batteries. This is particularly true of motion sensors.
Many device manufacturers have a line about this in the user manual for the device, but it’s good practice in any case. 
(If you’re interested in more details on the discharge curve, see the following thread:
Batteries: Types/Sizes/Uses/Opinions/mAH/Life/ReportingLevels/etc )
Other Alternatives
A) sensors with built in rechargeable batteries. As @bry mentioned, Aeotec has some models, but so do some others. Available on both the US and EU frequencies.
B) sensors with 10 year batteries. Sensative has a patent on their long life very thin batteries and make a line of zwave sensors that work with SmartThings. Expensive, but popular. Available on either the US or EU frequencies.
C) Plug in sensors. There are some sensors that can operate on mains power. Again Aeotec has a few models, but you may also be able to use dummy batteries for this.
There are several existing threads where people describe how they converted battery powered devices to mains power. Go to the Quick Browse Lists in the community-created WiFi, look down near the bottom of the page for “Project Reports” and choose the “power” list.
For further suggestions, please specify the country you are in, as device selection does vary. 
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The battery life on the Aeotecs is long enough that I haven’t paid much attention to it. I doubt it’s over a year as stated in the specifications but I’m sure that you can get several months out of them. They get occasional use in my installations so I am not sure if heavy use would diminish that.
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The reason is the rechargeables have a different discharge curve which will cause two problems.
Interesting, didn’t know that.
For further suggestions, please specify the country you are in, as device selection does vary.
I’m in the US. What’s a good place to browse through available devices?