Many mobile or portable devices are supplied with electrical energy by batteries. These include flashlights, children’s toys, radios, radio microphones, radio mice, weather stations, medical devices, measuring instruments, kitchen scales and many more. So-called primary cells = non-rechargeable batteries can only be used once, i.e. until they are exhausted. But it is a waste to dispose them! Because with a little bit of electronics, you can use old batteries. By Lothar Göde (Germany)
Over the course of time, mobile devices accumulate quite a few batteries, which then find their way in the collection boxes of supermarkets, etc. However, even apparently empty batteries can still contain amounts of residual energy! This is especially true for the much-used types like AA and AAA. Whether a battery is empty or not depends on how high the currents drawn are. At low loads with…