My wife has insisted for some time that you can 'train' a battery in order to optimize its performance and lifetime. [more inside]
On a device with 2 batteries, say for an example, a remote control with 2 AA batteries, the instructions for the device say, when the time comes, to replace both batteries, not just one. As if replacing one battery, while it will supply enough energy to run the device, will somehow damage the device. Is this just a ruse to sell more batteries?