I told my engineering students for decades that the next Bill Gates would be the innovator who successfully reimagines the modern storage battery. An aside, I quickly found out that citing Bill was a much better motivator than, say, Isaac Newton or Albert Einstein, because students had a lot more interest in money than fame :)
A battery that lasts 100 years should more than qualify.
Scientists at Stanford University in Palo Alto, CA have solved a key problem involved in the longevity of the modern storage battery, leading to the practical realization of approximately 40,000 charge/discharge cycles per cell. Contrasting this with a common LIon (lithium ion) battery, which has a life expectation of about 400 cycles, this new technology represents a 100x improvement in storage battery longevity.
This is a green energy breakthrough, because the cost of maintaining massive battery banks every 15 months or so represents a severe limitation on the potential of most green technologies. Indeed, the battery array has always been the alternative energy bottleneck. It's easy - and these days, relatively inexpensive - to put up solar arrays or wind fields which generate massive amounts of low-cost energy, which is all well and good as long as the sun is out or the wind is blowing. But without a satisfactory means of mass storage, we would have to turn off our computers when the sun went down or when the wind generators aren't turning.
Not only will the deployment of a mass storage array which utilizes this new technology theoretically sustain charging cycles for over 100 years, but the electrolytes they use are an inexpensive water-based compound. Contrast this with a modern LIon storage cell, which uses expensive organic electrolytes or molten salts, which constitute the greatest part of the aggregate cost of the storage cell.
The secret is a new electrode material derived from nanoparticles of copper hexacyanoferratte. In a conventional storage battery, the electrode chemically degrades over time, which is the major delimiter on the life of the cell. The open framework in the copper nanoparticle electrode has large gaps, which allow ions to flow through it without degrading the electrode itself.
According to Stanford, the remaining hurdle is to construct a similar anode (which also degrades), but suitable candidates - leveraging nanotechnology as well - are in the design phase now.