The Karpen Pile is claimed to be a battery that has provided continuous energy for over 60 years, making it either a supremely effective method of storing energy or a hoax, furthermore some newspapers describe it as a perpetuum mobile, but most scientists disagree since such a device would violate the Second law of thermodynamics. The device is housed at the Dimitrie Leonida National Technical Museum by 2010. There were claims that it had been working there continuously for 60 years. The prototype has been assembled in 1950 and consists of two series-connected electric piles moving a small galvanometric motor. The motor moves a blade that is connected to a switch. With every half rotation, the blade opens the circuit and closes it at the start of the second half. The blade's rotation time had been calculated so that the piles have time to recharge and that they can rebuild their polarity during the time that the circuit is open. It uses platinum and gold electrodes and no detectable corrosion effect happens. Normally, one electrode should corrode and lose ions which should deposit around the other electrode. Apparently, this does not happen. The cell is just as basic as it gets: two pure electrodes immersed in pure sulfuric acid. Everything sealed. However, the fact that the electrodes are made of gold and platinum (the least reactive metals) and the very low density of the generated power could be the reason why the pile is still working.