A number of tech blogs are reporting a humorous and green-sounding new battery technology: the NoPoPo Japanese battery that can be recharged by filling it up with… urine. Sounds great, right? Free electricity! The ultimate recyclable resource! Not only that, but this battery can run on any liquid – beer, tea, juice, coffee… even water!
That’s where I stopped to think. Water? Really? How does a battery “run” on water? Every now and then a video goes around showing some garage inventor who has managed to generate energy from water, or salt water, or something like that. Every time it’s proven to be a hoax. Because you just can’t create energy out of nowhere; to quote the Simpsons, we follow the laws of thermodynamics in this household.
So then how do these batteries work? Nearly all of the posts refer to the fact that “the liquid reacts with a mix of carbon and magnesium”. They also mention the fact that the battery can only be recharged a limited number of times. But if the liquid were the fuel, why would it be limited like that?
The best explanation I found was in a comment by “retired Chemistry Professor” on the blog Hexus. He pointed out that when the liquid is introduced it allows the magnesium to oxidize, thereby generating a current. As soon as the magnesium runs out, the battery is dead. In lieu of an official explanation of the technology from the NoPoPo people, this sounds the most plausible to me.
So is there value to this battery? Maybe a little. It claims to be made of environmentally benign materials. Also, whereas a regular battery slowly dissipates its charge no matter what, maybe this one would be able to “hibernate” in between liquid injections, thereby giving you the full potential of the magnesium inside. But the battery is only rated to give you 500 mAh (milliamp hours) – as opposed to 1700-3000 mAh in a normal alkaline battery – and it’s only powerful enough to run a small device like a clock or a radio (when’s the last time you even used a portable radio?).
Moral of the story – be skeptical when someone tells you something runs on water.
written by Nick, February 19, 2009
written by Fred, July 16, 2009
|< Prev||Next >|