Chris Greening kept getting emails from Amazon – at some point, he had hooked up some Hue devices to an Alexa and he must have clicked a button to remind him about to order supplies. The result were emails saying the battery was low and buy replacements. Chris investigates:

The battery level is measured approximately every 15 minutes and it’s pretty noisy, but we can smooth it over multiple readings and get quite a decent plot.

We keep our heating off overnight, and it turns off fairly early. This means that during the night the room with the switch in gets pretty cold. And as the room cools down the battery performs less well. Then around 6 or 7am, the heating comes back on and the battery starts to warm up. The battery performance goes up as it gets warmer!

I did a few measurements of the battery at different temperatures, room temperature, after being in the fridge for a while, and then after being warmed to body temperature. It’s quite a dramatic difference in performance.

Check out the video below and more on the blog here.