Why Aren't Batteries Better Yet?

Readers ask -- and you answer

Battery

RTC (GNU licensed)

PopSci reader VectorAKA2004 raises a good question: "I wonder why batteries are lagging behind portable technologies. We advance cell phones and all kinds of things so far and still barely have the power to run them. We have yet to create batteries that can efficiently store solar energy, or other renewable energy sources."

What do you think? Discuss in the comments.

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