Arduino Measures Remaining Battery Power With Zero Components, No I/O Pin. 22 Comments . by: Donald Papp. ... Whether that is relevant depends on the circuit in question, ...

How long can you keep an Arduino circuit running on three AA batteries? With careful design, [educ8s] built a temperature sensor that lasts well over a year on a single charge of three 2250 mAH rec… ...

The circuit works by measuring the voltage across a fixed load every second until the voltage drops to less than 0.2V. ... Topics Arduino battery DIY Electronic Geek GeekDad. Read More.

Oki Printed Circuits has showcased technology that embeds a 170μm-thick thin-film all-solid-state lithium-ion (Li-ion) rechargeable battery into a 0.8-mm-thick printed circuit board (PCB).