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Electric Vehicle Batteries and Electrical Storage

From cradle to grave, driving an electric vehicle (EV) is cleaner than driving an internal combustion engine (ICE) vehicle. Since 2010, when modern EVs came on the market in the U.S., EV batteries have improved dramatically. While concerns about battery cost, safety, range, longevity, and environmental impacts have largely been resolved, we address lingering concerns here.

EV Batteries: Getting Better All the Time 

Battery costs are dropping

With battery costs dropping, Light duty EV’s have reached cost-parity with their ICE counterparts, Medium- and Heavy-Duty EV’s are currently more expensive than their ICE counterparts, but programs like Washington Zero-Emission Incentive Program (WAZIP) exist to incentivize their adoption. Economies of scale have helped reduce costs from $1,000 per kWh to about $100 per kWh.

EV manufacturers use different battery designs and battery management systems to improve performance and safety. Manufacturers frequently submit patents for new battery technology as they strive to reduce environmental impacts while achieving safety, performance, and production goals.

Do EV batteries need to be replaced every three to five years?

No. Li-ion batteries in EVs have never needed to be replaced that often. While fear of battery degradation was a concern with lead-acid batteries or in pre-2013 EV models, gains in battery technology negate this concern about frequent battery replacement. New EV batteries have four to six times the capacity of older batteries and provide much longer ranges.

Battery safety continues to improve

Significant advances in battery chemistries have resulted in important improvements in battery safety. EVs with modern batteries are not more prone to catching on fire than ICE vehicles. In fact, ICE vehicles are responsible for the nearly 200,000 highway vehicle fires that occur each year in the U.S. (National Fire Protection Association). The heat release and hazards of an EV fire are comparable to those of an ICE vehicle fire.

A battery management system (BMS) keeps the EV battery at the optimal temperature to prevent overheating. This is especially important while charging, during heavy-duty operation or when driving at temperatures below 0° F. The BMS also makes charging more efficient and improves EV battery longevity.

EV batteries have safety systems to prevent electrocution risks. All EVs are designed to meet international standards to ensure they do not present unusual hazards in flooding situations. Electrical components are well sealed and integrated safety systems are designed to minimize the potential for electrical shock in a crash or water submersion.

To reduce any risks that may occur if an EV is damaged and parts of the electrical system are exposed, EVs include the following systems:

  • An impact sensor triggers a series of safety systems to disconnect the high-voltage battery electrics from the rest of the car.
  • Ground-fault detection systems continually test for electrical connections between the metal vehicle body and the high-voltage system. If a fault is detected, the ground-fault system shuts off the electrical supply to the high-voltage components.
  • Fuses inside the EV battery pack disconnect areas of the battery if needed.

EV fires can be more difficult to suppress because an EV battery is less accessible to externally applied suppressant and can re-ignite if it is not cooled sufficiently. As a result, lots of suppression agent is needed to extinguish an EV battery fire, cool the battery, and prevent re-ignition. First responders are trained to use reasonable caution when responding to an EV battery fire. Fire safety research, training, and policy changes are underway to improve the safety of each generation of EV batteries.