"Do oil companies ever crush small but potentially huge ideas ... like electric cars"...
Oil companies and OEM's all do it.
Case-in-point - In 1973 an engineer friend of my brother-in-law that worked at a large corporation in my area redesigned a Motorcraft (Ford) 600 cfm carburetor, that was on his 1972 Maverick drag car w/ 302 c.i. V-8 engine. He 'upped' his gas mileage from the normal 8-10 mpg to almost 20 mpg; around town! And it STILL turned a low 10 seconds in the quarter mile.
He approached Ford who bought his design and patent. Nothing ever happened with it; canned... Some of his technology may have been used later on with fuel injection applications; who knows but bottom line it seems as if much of this technology is being orchestrated to 'happen' only when the big money folks are well positioned to benefit the most from it.
Then and only then will much of this new technology be accepted and used. The "little" guy usually ends up getting the short end of the stick through it unfortunately.
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