▎ 摘　　要

NOVELTY - A natural polymer-based composite solid electrolyte, comprises natural polymers or modified natural polymers, composed of inorganic or organic fillers and metal salts, using in-situ compounding or blending compounding methods, where the amount of the filler accounts for 0.1-50 wt.% of the total mass fraction of the natural polymer or the modified natural polymer. USE - The natural polymer-based composite solid electrolyte is useful in secondary batteries e.g. lithium-ion batteries, sodium-ion batteries, potassium-ion batteries, magnesium-ion batteries, calcium-ion batteries, zinc-ion batteries, and aluminum-ion batteries, as well as in supercapacitor and electronic sensors. The secondary batteries include lithium metal batteries, lithium-ion batteries, lithium-sulfur batteries, lithium-air batteries, sodium-ion batteries, potassium-ion batteries, magnesium-ion batteries, calcium-ion batteries, zinc-ion batteries, and aluminum-ion batteries. ADVANTAGE - The electrolyte: has high room temperature conductivity and high ion migration number; has good film-forming property, high ion transmission performance; has excellent battery performance under high current density and high multiplying power; has wide source, low cost, environment-friendly, simple and easy to prepare, suitable for industrial production, expanding the raw material type of the battery and the super capacitor and application; and exhibits very excellent mechanical performance for inhibiting dendritic crystal growth, improving the safety of battery and super capacitor, and excellent cycle stability under the condition of large multiplying power and large current density, and can be applied to sodium battery, potassium battery, magnesium battery, calcium battery, aluminum battery, zinc battery, super capacitor or electronic sensor. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for the preparation method of natural macromolecule-based composite solid electrolyte.