I'm just brainstorming here, really. How might resistance change across a sample of metal due merely to the cycling of current across it? This type of cycling happens in electric cars each time the car is turned off and on, and this is exactly the application I'm thinking about. Here's what I was thinking: The effect of the current by itself will likely be unapparent over a car's standard design life-time (say, 250,000 miles), but the electroplastic effect combined with the effects of alternating loads (i.e. the car shaking up and down due to bumps in the road) will cause certain joints in the electrical system's high-amperage parts to experience increases in resistance over the life of the car. The alternating loads by themselves would, of course, cause increased resistance due to the microstructural effects of fatigue, but I have a feeling that the effect would be compounded via the electrical current. All of this ties back to the efficiency of the car's battery, which would of course decrease over time if the power loss due to the resistance of it's internal circuitry increased over time. Anyone else have other angles from which to approach this?