Years ago, I believed that electric vehicles (EVs) had little chance of becoming more than niche-market vehicles due to battery concerns, charging issues, and low range.
However, after conducting extensive research on EVs for Family Handyman, my opinion and attitude have completely changed, particularly regarding batteries. EV batteries are engineered to outlast the vehicle and can perform reliably for 10-15 years, depending on climate and charging cycles, according to a life-cycle analysis by the National Renewable Energy Laboratory. A separate study by the U.S. Department of Energy Alternative Fuels Data Center found that new electric vehicle lithium-ion batteries may last between 12-15 years in moderate climates and 8-12 years in extreme climates. Additionally, federal regulations require that all EV batteries sold in the United States come with warranties of at least eight years or 100,000 miles. If a new EV battery fails, it is likely to be covered by the original equipment manufacturer’s (OEMs) warranty, which can provide insight into the battery’s life expectancy because EV manufacturers do not want to replace expensive EV batteries by overestimating their durability.
OEM EV battery warranties may contain exclusions due to replacement costs, which could include using non-standard charging stations or non-approved aftermarket parts, using the EV as a stationary power source, damaging the battery coolant reservoir, not installing software/firmware updates, repairs done by non-certified technicians, lifting the vehicle by the battery instead of designated lift points, general abuse, lack of maintenance or failure to make necessary repairs.
How do EV batteries degrade? There isn’t one single factor causing this. Similar to traditional lead-acid batteries, every time a lithium-ion battery cycles, its chemical and physical reactions decrease, gradually diminishing its potential to generate electricity. In technical terms, as an EV battery is used, a layer of solid electrolyte interface (SEI) builds up inside the battery, which blocks the passage between the electrolyte and electrodes, slowing the chemical reaction that eventually affects battery performance. Overcharging, cold temperatures, or leaving an EV parked for long periods with less than 20% charge can also cause battery degradation.
Translation to SCI paper style:
The OEM warranties for EV batteries may have exclusions due to replacement costs, such as using non-standard charging stations or non-approved aftermarket parts, using the EV as a stationary power source, damaging the battery coolant reservoir, failing to install software/firmware updates, performing repairs done by non-certified technicians, lifting the vehicle by the battery instead of designated lift points, general abuse, lack of maintenance, or failing to make necessary repairs.
How EV batteries degrade is not due to a single factor. As with traditional lead-acid batteries, the chemical and physical reactions of lithium-ion batteries decrease each time they cycle, gradually diminishing their potential to generate electricity. In technical terms, as an EV battery is used, a solid electrolyte interface (SEI) layer forms inside the battery, which obstructs the passage between the electrolyte and electrodes, slowing the chemical reaction that affects battery performance. Overcharging, cold temperatures, or leaving an EV parked for long periods with less than 20% charge can also cause battery degradation.
Corrosion caused by moisture during battery manufacturing can damage battery cells, leading to reduced battery performance and fewer miles per charge. However, EV battery degradation is minimal thanks to the battery management system (BMS). A study on 6,000 EVs found that over six years, batteries lost less than 3% capacity per year. To extend EV battery life, it is recommended to charge the battery to 80%, use Level 1 or 2 chargers for overnight charging, and avoid charging the battery to 100%. Other tips include driving at moderate speeds, maintaining proper tire pressure, and keeping the battery cool.
