Easy Energy, an Israeli development-stage start-up company, has invented YoGen, a small hand-powered generator for cell phones and small electronic devices. Much like pulling a yoyo string, user’s can charge YoGen by pulling a cord which immediately activates its internal generator. The device is small enough to be carried anywhere, measuring only 45mm x 92 mm, 18 mm thick (1.75" x 3.6", 0.7" thick). Therefore, YoGen eliminates the need to carry around different chargers and will prevent situations when one is ‘stuck’ without a battery after having left the charger elsewhere.
YoGen consists of a patented miniature generator and a built-in ~2,000 mAh lithium battery, which stores extra energy like a reservoir. When charging a cellular phone, "typical talk-transmission power is about 1 watt. With the 3.7V lithium-ion batteries, discharge current can reach 330 milliamps. Standby current is much lower and when the screen is off it is less than 10 milliamps," the company explains.
Each pull of the cord generates power of 20 watts peak. Stator coils integrated into a PCB are activated via the patented design of the rotor’s permanent magnetic component layout, thus providing for high power of the generator. Instead of a complex gear mechanism used in other hand generators, YoGen uses a simple rotational multiplication concept, created by building the cord’s pull and return mechanism on a separate axle.
Even after the pulling cycle has ceased, the effective generation cycle is still extended thanks to a flywheel system, which is incorporated in the generator’s rotational mechanics. In addition, a charging and protection circuit monitors both internal and external battery conditions to ensure that overcharging is avoided. The charge of the internal and cellular batteries is shown via LED indicators.
"A second model (currently in development) will provide enough power for laptops and camcorders and can be built to meet military specifications and security applications", explains the company.
TFOT recently covered HYmini - a handheld mini ‘green’ power station. Measuring only 5.4 inches (134mm) X 3.4 inches (87.5mm), it uses three power sources: renewable wind power, solar power, and the conventional electric power outlet. TFOT also reported on Philips' Power4Life seriesportable energy chargers and a multi-charger called 'Freeloader', developed by U.K. Company Solar Technology.
More information about YoGen is available on Easy Energy’s website.