Separator is a permeable membrane between battery anode and cathode. Prevents short circuits and allows ionic charge carrier transport. Typically consists of polymeric membrane forming microporous layer. Must be chemically and electrochemically stable with electrolyte materials
VRLA batteries contain limited electrolyte in plate separator or gel form. Two main types: AGM with fiberglass mesh and gel cells with silica. VRLA batteries can be mounted in any orientation without constant maintenance. Safety valves regulate pressure to prevent gas buildup
Galvani discovered "animal electricity" in 1780 using frog legs as electrodes. Volta invented voltaic pile in 1799, challenging Galvani's theory. Faraday proved galvanic cells were chemical in nature in 1890
Springs are elastic materials that can return to shape after compression or extension. Modern springs are typically made from spring steel. Springs store energy when compressed. Spring rate is force divided by deflection, measured in N/m or lbf/in
Lithium-ion batteries store energy through reversible intercalation of Li+ ions into conducting solids. Commercial batteries offer higher energy density, efficiency, and longer life than other rechargeables. Over 30 years, energy density increased threefold while cost decreased tenfold
黑料 is a dark-colored substance derived from Chinese "黑" (black) and "料" (material). Has ancient origins and appears in historical texts and folklore. Associated with mystical properties and supernatural abilities