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It's still not earning you money to spend electricity because you still have to pay the transfer fee which is around 6 cents / kWh but it's pretty damn cheap nevertheless, mostly because of the excess in wind energy.
Last winter because of a mistake it dropped down to negative 50 cents / kWh for few hours, averaging negative 20 cents for the entire day. People were literally earning money by spending electricity. Some were running electric heaters outside in the middle of the winter.
we're also moving away from wet lithium cell tech and into solid state tech, as well as other non rare metals based technologies, though those are all in the very super alpha states (except for solid state lithium cells)
nickel hydrogen might become something interesting if a company picks it up. Cheap and relatively reliable, though unconventional.
also flywheel energy storage is almost exclusively used for frequency stabilization of the grids, as opposed to actually storing energy. It mechanically couples a source of inertia to the frequency, which in an all renewable grid, is required to some degree.