How long does a Six-cell lithium ion battery hold a charge and last for?

im building a laptop and im wondering if a 6-cell battery is enough

Depends on the laptop. The # of cells is no indication of its storage capacity except in a VERY general terms.

Battery is like a fuel-tank. Without knowing what kind of engine you plan for it to feed, and how you drive (like a maniac, or like Mr. Rogers), it’s impossible to know how well it’ll serve your needs.

Dry Cell Battery Box Idea

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