I've been doing some reading on the wiki and Electrolyzers seem like a decent idea to increase the capacity of enery storage, but are they actually useful in practice? They're not e-net blocks, so you can't hook cables to them (can you? I tried this in the past and I got nothing in or out of the block). They require at least an MFE to function and the output is tied up pointing at the Electrolyzer, so you can't use the MFE for anything else. I suppose you could move the cells from a "source" MFE/MFS to another Electrolyzer hanging off another MFE... but at that point, why deal with the loss (just use Energy Crystals instead and get ~6x the power per run)?
There's got to be a reason for them to exist, but I'm not seeing it. What am I not seeing?