Although the term ‘quantum battery’ is a bit of a vague term, the cell that [Kieran Hymas] et al. demonstrate in a recent paper does seem to suggest that it uses quantum effects to charge faster than would otherwise be possible, with this rate increasing faster than its volume, meaning at a superextensive rate.
The general idea behind a quantum battery is that these somehow use a quantum effect to store and release energy faster than would be possible using classical physics. First proposed in 2013, the initial Dicke model saw its theoretical quantum advantage shot down by 2020, leading to the search for alternative models.
We have previously seen claims of a quantum advantage in batteries based on the Sachdev-Ye-Kitaev model, such as by [Davide Rossini] et al., but this new paper may be the first prototype cell demonstrating a reproducible effect.
In the here demonstrated cell a microcavity is created with strong light-matter coupling, allowing for both energy storage and discharging, with the illuminated particles super-absorbing the light with what the researchers claim to be due to these particles cooperating using a quantum mechanism. Effectively scaling up the cell would thus scale up the charge- and discharge rate faster than in a conventional chemical cell.
Whether this demonstration can be replicated and expanded upon remains to be seen, naturally. The stored energy in this experiment was very small and the storage time only very brief, so for now it serves primarily as an interesting experimental result for researchers to dig through.
Running the frame calculations for the greyscale mode without rendering to the screen pushed that up to 107.6 mA, with even in the 30 FPS greyscale mode the display thus only consuming about 7.4 mA, which is vanishingly small. Clearly the low-power claims of e-paper remain intact even at higher framerates.
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