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A comment on Samsung Develops Battery Material with 5x Faster Charging Speed. Parent comment

Re:Samsung Develops Battery Material with 5x Faster Charging... by mark-r on Wednesday November 29, 2017 @12:30AM (#15804807)
There must be, certainly there are no graphite brushes in your spinning hard disk. That might not have been a common motor design back when I had that razor though, but they certainly could have used a beefier piece of graphite.
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Re:Samsung Develops Battery Material with 5x Faster Charging... by clort on Wednesday November 29, 2017 @01:50AM (#15805115)
hard disks have brushless motors

  https://en.wikipedia.org/wiki/Brushless_DC_electric_motor
they are usually more expensive but have been around for a long time.

AFAIK there is no substitute for graphite in a brushed motor, it is needing to transfer power to different sections of a rotating part in turn and does so by rubbing over a set of copper strips. That the graphite is soft is why it works well but also why it wears out rather than the commutator, which will survive several sets of brushes.

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