Editing Torpedo (section)

===Electric batteries===
[[File:Torpedo model Z-13 mg 5165.jpg|thumb|Electric batteries of a French [[Z13 torpedo]]]]

Electric propulsion systems avoided tell-tale bubbles. [[John Ericsson]] invented an electrically propelled torpedo in 1873; it was powered by a cable from an external power source, because [[Battery (electricity)|batteries]] of the time had insufficient capacity. The Sims-Edison torpedo was similarly powered. The Nordfelt torpedo was also electrically powered and was steered by impulses down a trailing wire.

Germany introduced its first battery-powered torpedo shortly before World War II, the [[G7e]]. It was slower and had a shorter range than the conventional [[G7a]], but was wakeless and much cheaper. Its [[lead–acid battery|lead-acid]] [[rechargeable battery]] was sensitive to shock, required frequent maintenance before use, and required preheating for best performance. The experimental [[G7es]], an enhancement of the G7e, used [[primary cell]]s.

The United States had an electric design, the [[Mark 18 torpedo|Mark 18]], largely copied from the German torpedo (although with improved batteries), as well as [[Mark 24 Mine|FIDO]], an air-dropped acoustic homing torpedo for anti-submarine use.

Modern electric torpedoes such as the [[Mark 24 Tigerfish]], the [[Black Shark torpedo|Black Shark]] or DM2 series commonly use [[Silver-oxide battery|silver oxide batteries]] that need no maintenance, so torpedoes can be stored for years without losing performance.