From cradle to grave, driving an 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 and lithium-ion (Li-ion) battery technology is now standard. While concerns about battery cost, safety, range, longevity, and environmental impacts have largely been resolved, we address lingering concerns, current and promising battery technologies, and electricity storage technologies here.
Battery costs are dropping
With battery costs dropping, EVs are expected to reach cost parity with ICE vehicles soon. Economies of scale have helped reduce costs from $1,000 per kWh to about $100 per kWh. (A kWh is the amount of energy a machine needs to run for one hour.)
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 3 to 5 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 4 to 6 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.
Battery production is evolving to reduce human and environmental impacts
A Li-ion EV battery pack is made up of hundreds—even thousands—of individual cells bundled together to hold the electrical charge. Each cell includes a positive terminal (cathode), negative terminal (anode), and a fluid that allows electrons to travel between the cathode and anode so charging and discharging can occur. A battery pack enclosure keeps the cells together and operating as a single unit.
In the 1990s, advances in Li-ion battery technology were driven by the increase in portable electronics such as laptop computers, mobile phones, and power tools. The EV marketplace has benefitted from these advances in the performance and energy density of Li-ion batteries.
Li-ion batteries contain minerals including lithium, nickel, cobalt, copper, manganese, and graphite. To addressconcerns about mining and processing these minerals, battery manufacturers monitor and investigate material supply chains to:
- Suggest alternative battery composition that uses raw materials that are readily available, like silicon and ceramics, and new battery chemistries and designs.
- Increase domestic mining and other solutions for extracting and processing raw materials to build a domestic battery supply chain.
All vehicles—EVs and ICE—rely on mining and extraction of rare earth minerals. To reduce safety concerns, mining is highly regulated and monitored by the Initiative for Responsible Mining Assurance and overseen by groups such as Amnesty International to prevent human rights abuses.
Increasing battery production will reduce costs
Manufacturers are working to increase mineral supplies and improve battery manufacturing to meet growing demand. A number of large battery gigafactories are being developed to increase battery supplies worldwide, producing billions of watt-hours of cells to support the transition to EVs. For each doubling of manufacturing capacity, battery costs drop by about 20%.
Battery re-use and recycling are improving
When the capacity of an EV battery drops below 70% or 80% after about 10 years of use, it may no longer be strong enough to power the car but it can still be put to good use, such as providing energy storage for residential solar or adding capacity to older EVs.
The battery pack itself can be refurbished by replacing spent cells. Refurbished batteries are readily available. However, the rapidly falling cost of producing new batteries and the complexity of some proprietary battery designs may make it cost-prohibitive to use repurposed batteries.
If an EV battery can’t be reused, it can be recycled. The ReCell Center was established by the U.S. Dept. of Energy in 2019 to support closed-loop recycling in response to the increasing number of Li-ion batteries used in electronics and EVs.
The ReCell Center is researching new ways to recycle these batteries, encourage local markets to use the recovered mineral components (lithium, cobalt, and manganese), and embrace new secondary uses, such as battery storage and distributed energy projects. Repurposed batteries could serve an additional 6 to 10 years in a lower-power, stationary application” such as storing energy from solar.
Manufacturers are standardizing battery designs and developing new battery chemistries that make it easier to disassemble, reuse, and recycle components recovered from spent batteries. This reduces the need for new raw materials, lowers the battery’s lifecycle impact, and improves energy security by reducing imports. Companies have developed circular supply chains where end-of-life products like batteries and electronics are “mined” for elements that can be re-used, transforming a waste stream into a supply chain.
These factsheets prepared by the WSU Energy Program focus on the current state-of-the-art of EV batteries and anticipated improvements.
These factsheets prepared by the WSU Energy Program address the primary types of energy storage as they relate to electric vehicles.