Miniaturized Al/AgO coin shape and self-powered battery featuring painted paper electrodes for portable applications

This work presents the development and optimization of a very low cost, miniaturized and lightweight aluminum/silver oxide (Al/AgO) primary battery. The system is implemented on painted paper supported electrodes and it is activated using a small amount of water. The anode contains an improved composite based on aluminum powder. The cathode is made using an electrical conductive silver epoxy ink. The device displays a paper-based core comprising the electrodes and the paper matrix separator, modified with a highly concentrated dry potassium hydroxide salt, inside a flexible laminated plastic structure that provides sturdiness to the system making it safe and portable for the user. The battery turns on by applying 80 μl of water and as a result the system produces a maximum capacity of 0.5 mAh when 1.6 mA cm−2 are applied. The generated electrical power of two batteries in series is then used to power a LED during approximately one hour. Although there is room for improvement, these results allow envisaging the battery as a real commercial portable power source and allow planning potential uses of this energy to power microelectronics demanding low power consumption, such as sensors or wearable electronics.