How much energy can each storage chemistry hold per litre, and does the ranking by weight survive?
research/energy-volumetric
How much energy can each storage chemistry hold per litre, and does the ranking by weight survive? Volumetric ceilings from reactant densities: zinc-air 9,659 Wh/L with air, Li-ion 1,382, lead-acid 724, hydrogen 1,314 at 700 bar.
What it found
Volumetric ceilings (Wh/L) for the couples of energy-density, from the sum of reactant mass over assumed handbook density. With oxygen taken from air, zinc-air reaches 9,659 Wh/L, lithium-oxygen 6,104 and aluminium-air 5,887, against 1,382 for graphite/LiCoO2 and 724 for lead-acid. The ranking changes with the basis: lithium-sulfur beats graphite/LiCoO2 by 6.8 times per kg but only 2.1 times per litre (lithium is light and bulky), while zinc-air beats lead-acid by 6.4 times per kg and 13 times per litre. Hydrogen holds 1,314 Wh/L at 700 bar and 2,314 as a 20 K liquid. Sand at 500 °C holds 171 Wh/L as heat. Active material only; densities are assumed, not checked.
A figure from its own output
Paper, code and results
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Produced with AI assistance (Claude). Results are from the code in this repository and are simulated or stylised unless the abstract says otherwise; nothing here implies affiliation with or endorsement by any lab, researcher or company cited. MIT licensed.