A hand-cranked battery that can be charged by cranking.

The advantage of rechargeable batteries is that they can be repeatedly charged and used, which is much more environmentally friendly compared to regular batteries that are discarded once used. However, this hand-cranked rechargeable battery could be considered the ultimate in eco-friendliness. In addition to being able to charge with a regular charger, its unique feature is that it can be charged simply by cranking the handle, without any additional components - entirely powered by manual effort. This AA-sized nickel-metal hydride battery contains five internal components: a rechargeable nickel-hydrogen battery, a drive shaft, a spool, a permanent magnet, and a rubber shock absorber. The battery's capacity is half that of a standard AA battery, with most of the power generated by the spool. When the battery is cranked, the permanent magnet moves up and down along the center of the drive shaft and spool, generating electricity in this way. The rubber mount absorbs vibrations and helps the magnet bounce back. With such a hand-cranked rechargeable battery, if you're out and about and find yourself in an emergency situation without power, you can generate electricity simply by cranking it. Of course, if combined with solar charging functionality, such batteries could be made in various shapes in the future and widely applied to electronic devices like mobile phones, computers, and digital cameras, offering immense potential.