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Comment by pacman83 | Hacker News Reader

Just last week I was thinking we need solar cells wired up in a tree structure with batteries integrated into the tree so that we don't need to combine series and parallel or have the drawbacks of either. Is anybody doing that? I presume they would need to be connected with fluids, electrolyte in channels instead of with wires. Or have I just reinvented the tree?

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Sounds similar to a redox flow battery (https://en.m.wikipedia.org/wiki/Flow_battery) which uses tanks of anolyte and catholyte solutions to store power. Energy density for Vanadium based redox flow batteries are only 20Wh/kg but might be worth it given the volume of a typical (normal sized) tree.

What problem are you trying to solve?

That is always the most important question, isn't it?

I am looking at RV applications, thinking series would be ideal to reduce wiring cost, but just learned that a small patch on one panel of shade lowers current in the whole series, when wired that way. If there's some way they could be wired as a tree, with the high amperage portion of the circuit fairly short, that seems more efficient. But then I guess I have just reinvented the power grid... I'm talking about residential scale, though, or smaller.

So you're trying to connect an array of solar panels in series, such that shading one doesn't limit the current of the others. Isn't that normally solved using bypass diodes?

I guess you just solved my problem. This is a topic I'm just beginning to look into. Thank you.

But now I'm wondering why are panels made this way? I mean internally they're wired in series or at least substantially so. and I've read that shading a small portion of one panel will drastically reduce the output of that one panel. Is it possible to create a panel (e.g. nominally 12 volt system) with bypass diodes inside it? If so then why wouldn't they have been doing this all along?

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