el33t
Well-Known OPE Member
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I have often thought that electric tool technology would jump light years ahead if it could ever be figured out how to make a battery that stores AC current. Or, create a fuel cell that could accomplish the same thing in a power tool size format.
AC produced directly in electrochemical cells? I don't think so. AC is generated when a conductor moves in a magnetic field.
Besides, it wouldn't make much sense.
We produce alternating waveforms at the frequency we need using solid-state switches with efficiencies exceeding 90%.
In general, AC with a (grid) frequency of 50/60 Hz is very inefficient for power conversion purposes. Therefore, inverters operate at frequencies ranging from tens of kilohertz all the way down to a few megahertz.
AC from the power grid is increasingly used via VFDs rather than directly, especially for induction motors. VFDs convert AC to DC and then to variable-frequency AC, saving energy by optimizing motor speed for partial loads.
Many household appliances, like fridges, now use inverter-driven induction or permanent magnet motors to improve energy efficiency by adjusting compressor speed.
In general, DC is much more useful in the modern world.
I don't see much chance of using fuel cells in the near future in handheld power tools, if only because of their limited current capacity. There would have to be some kind of breakthrough here, and that's not likely to happen, since they were invented back in the 19th century with the first commercial applications even before WW II.