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A comment on Solar-driven water splitting at 13.8% solar-to-hydrogen efficiency. Parent comment

Re:Solar-driven water splitting at 13.8% solar-to-hydrogen e... by Someone on Thursday November 18, 2021 @05:58PM (#29271685)
> Batteries are great for storing electricity efficiently

In some cases not even that. Modern Lithium-ion batteries are quite good, but self-discharge still is 2-3%/month. So, if you want to store for months (say charging a battery using the summer sun to heat a house in winter), you easily lose 10% to self-discharge, in addition to what you lose between charging and discharging.

https://en.wikipedia.org/wiki/Self-discharge#Typical_self-di... says NiMH batteries even lose 30% per month.

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Re:Solar-driven water splitting at 13.8% solar-to-hydrogen e... by 8bitsrule on Friday November 19, 2021 @02:30AM (#29274727)
It also says "Low self-discharge NiMH : As low as 0.25% per month ... introduced in 2005 by Sanyo, branded Eneloop "

70-85% retained after a year is a lot better. Charge in the same charger. I used to use regular NiMH infrequently, the worst way to use them. Low sd way better for that application. Also NiMH doesn't lose capacity delivering high currents like AA alkaline does.

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