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CloneEngineer t1_is3wx8s wrote

Reply to comment by [deleted] in South Korean researchers say they have developed an anode-free lithium-ion battery that is 40% more energy dense than existing batteries and will enable EVs to travel 630km (390 miles) on a single charge. by lughnasadh

Kw/h is a meaningless unit. Kw has units of kilojoules/sec, it's already a rate. The unit kw-hr - or kj-hr/sec is a capacity unit cause the time "cancels". Kinda. Kw-hr units are strange in a lot of ways.

I don't think kw / kw-hr are intuitive units for most people.

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Billysmalltits t1_isxgqt8 wrote

So you're saying 1kW/hr, which obviously means a power output of 1kW for a time of 1 hour is less intuitive than saying 3.6 megajoules?

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CloneEngineer t1_isxhvzj wrote

You wrote the units wrong also. You want kw*hr, not kw/hr. Maybe not so obvious?

I'm saying kw is already a rate. It's units are J,/s. Kw/hr would have units of J/s-hr. That makes no sense. Another way to say you supply 3.6 MJ in an hour would be to say 1Kw-hr/hr. And hrs cancel to 1Kw.

Most people want kw*hr, not kw/hr. Kw/hr would be the rate of change of charging speed. Ie, I started charging at 1kw, an hour later I'm charging at 11kw, charging rate increased at 10kw/hr.

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