Mental models guide electric vehicle charging

Abstract

To discover conceptual and behavioral barriers to electric vehicle (EV) charging, in-depth interviews were conducted in person with experienced and novice EV users. Mental models were found to affect vehicle charging strategies. Novice EV users drew from their existing mental models for petrol refueling and misapplied them to EV charging. Most experienced users had developed new mental models appropriate for the physical and temporal realities of EV charging—they are adapted to diverse rates of charge, EVs' longer energy filling duration, co-location of EV charging with certain user activities, and EVs drivers’ shorter equipment engagement time. Three predominant mental models for EV charging were found: 1. Monitor the fuel gauge, when low, seek a refill location (from liquid-fueling model), 2. Prior to a trip, plan where and when to charge, 3. Event-triggered charging (unique to the EV mental model). Misapplication of liquid fuel models to EVs has detrimental effects: more effort and more frequent anxiety regarding recharging, buyer choice of EV characteristics mismatched to need, manufacturer oversizing of batteries, policy overemphasis on fast public charging, and restricted opportunity to reduce load on the grid. Solutions are suggested to forestall or minimize these detrimental effects and facilitate EV adoption.