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The electro-cells are a powerful energy source devised by human scientists at the Experimental Energy Research Laboratory. It is stated that if the electro-cells were to overload, they could start a chain reaction that very well could destroy the entire planet Earth.

Fiction

The Transformers cartoon

Megatron and his forces broke into the facility where the electro-cells were being held and stole them, planning to use them for the usual purpose (i.e. conquest). The Decepticons took the cells to a canyon, where they labored to find a way to extract the energy from the cells in a usable and non-exploding form. After an attempt by the Autobots to recover the electro-cells, and a ploy on the part of Mirage that involved his teammates briefly thinking him a traitor, the Autobots made a second effort to recapture the cells. In the end, Megatron decided that if he couldn't have them, no one could, and blew up the electro-cells himself. Optimus Prime later apologized to the scientists for the loss of their invention, but the scientists were mostly glad the Earth didn't blow up. Traitor

TransTech

The Transwarp Dominion Initiative of Nexus 208.0 Epsilon utilized electro-cells in an unmanned sentry outpost monitoring the aggressive Skriix of Skriixos V. Andromeda - Axiom Nexus News, 2015/05/12

Games

Transformers Roleplaying Game

Electro-cells were created by the scientists at the Experimental Energy Research Laboratory, and drew power directly from Earth's magnetic field. However, the slightest misadjustment cause a catastrophic chain reaction that would permanently disrupt Earth's magnetic field and cause mass destruction. Roleplaying Game Core Rulebook