They have ruled out two possibilities -- mechanical "impact" damage, like that caused by being dropped, or short-circuiting outside the battery.

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They also found signs of short-circuiting along with the thermal runaway.

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If all goes according to plan, the liquid computers, introduced into cells, will recognize viral markers, causing cells with those markers to shut down by short-circuiting their operations.

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The testing concluded there was no chance that short-circuiting would lead to a fire, and the odds of a smoking battery were one in every 10 million flight hours.

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New Jersey justices are short-circuiting the electoral process.

FORBES: Fact and Comment