The same as the ecological impact of constructing gas tanks and pipelines. Only using electricity from batteries doesn't have ecological harms, whereas burning gas does.

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ErroneousBosh an hour ago | parent [-]

Gas tanks are made from steel, which last time I looked was a lot cleaner to refine than lithium, and with a lot less energy input.

	▲	triceratops an hour ago \| parent [-]
		How so? Both require mining, separating metal from ore and so on. Steelmaking is done in blast furnaces that burn coal. Lithium can be refined by evaporating brine in large open ponds under sunlight. Let's see some actual numbers.