A lithium secondary battery comprising at least a negative electrode, a positive electrode and an electrolyte, and utilizing oxidizing and reducing reactions of lithium ions for charging and discharging, wherein an electrode having an active material which has at least an amorphous phase and a half value width not smaller than 0. The method further comprises formatting the plurality of communications on the at least one output device as a function of the number of communications of the plurality of communications and of at least one condition and a function of a communication characteristic. A product may have information code. The found value is converted into digital form by an analog-to-digital converter and stored in a correcting value storage device. Potential uses of the stress sensor include a pressure sensor, embedment in moving parts such as vehicle tyres, aircraft wings or machine parts, and in structures such as bridges where stray magnetic fields are a problem.