Battery replacements in electric vehicles are rare, with most replacements occurring during the vehicle’s warranty period, concluded a recent study by Recurrent Motors, which provides battery health reports and range forecasts for used electric vehicles.
Based on a sample of 15,000 vehicles, periodic researcher Liz Najman found that only 225 vehicles (1.5%) had their batteries replaced outside of the battery recall.
The study also found that battery degradation is not linear. It happens faster in the first few years of a car’s life, then slower as it ages.
Battery replacement can be a major problem for an EV owner. A new battery can cost anywhere from $5,000 to $22,000, and for a luxury brand like Jaguar, up to $100,000.
Although car manufacturers say EV batteries should last up to 20 years, little is understood about how they degrade over time, Najman writes, but so far it appears that EV batteries last much longer than any one would imagine because very few of them have. replaced even after the eight year 100,000 mile warranty expired.
“EV batteries are exceeding initial expectations because battery management systems are more complex than most people realize and early adopters are well educated about battery health,” Chief Marketing Officer Andy Gaberson told TechNewsWorld.
Get rid of fast chargers
Edward Sanchez, senior automotive analyst at global technology intelligence firm TechInsights, explained that engineers are designing modern EV batteries to last a typical vehicle for 150,000 miles.
“Some have gone longer,” he told TechNewsWorld.
However, the auto industry appears to be adjusting its view of a vehicle’s lifespan.
“The industry recognizes that most vehicles are on the road much longer than 10 years and 150,000 miles,” observed Sam Abuelsamid, principal e-mobility analyst at Guidehouse Insights, a Detroit market research firm.
“The average age of a vehicle on the road in the US is more than 12 years, and it’s not uncommon for vehicles to be between 200,000 and 300,000 miles on the road,” he told TechNewsWorld.
“The industry knows this, and it wants to minimize the owner’s risk of having to replace the battery during the useful life of the vehicle,” he continued. “They’re trying to match the life of the battery to the life of the rest of the car.”
Power batteries can last the life of a vehicle if they’re “not made,” notes Rob Enderle, president and principal analyst at the Enderle Group, a consulting services firm in Bend, Ore.
“What makes the batteries are Level 3 fast chargers, just like your smartphone battery will die faster if you constantly fast charge it,” he told TechNewsWorld.
Abuelsamid is also advised to minimize the use of fast chargers. “If you charge the battery more slowly, you put less stress on it,” he said.
Battery charging is a physical process that moves lithium ions and electrons within the cells. At faster charging rates, the physical processes occur more vigorously and more physical stress or micro-damage occurs to the battery materials.
Charging at very high voltages, such as DC fast charging, also generates a lot of heat, which is not ideal for battery life, he continued. DC fast charging is a double ham cheeseburger of charging. great when traveling but good to avoid every day.
Heat is a battery killer
Experts recommend not draining the battery below 10% capacity or charging it above 100% to prevent battery stress and premature dendrite formation.
“Battery degradation is usually caused by the formation of dendrites, which are metal protrusions that can accumulate on the lithium surface and penetrate the solid electrolyte, eventually moving from one electrode to the other and shorting out the battery cell,” Sanchez explained.
He noted that the exception to the 100% rule is lithium iron phosphate (LFP) batteries, which are recommended to be charged to 100% so that the battery management system can get a more accurate reading.
LFP batteries also typically operate at lower voltages than other chemistries, he said.
Lithium-ion batteries used in electric vehicles differ from batteries used in consumer devices in several ways. Consumer device batteries are designed to last only two or three years, while an EV Li-ion can power a vehicle for 150,000 miles and still retain 70% capacity.
One of the most important differences between lithium-ion batteries used in consumer devices and those used in power generation is thermal management, Abuelsamid noted.
“Batteries in laptops and phones don’t have thermal management,” he said. “There is nothing to control the temperature of the battery over its lifetime.”
“The faster you charge a battery, the more heat goes into that battery,” he continued. “Heat is a killer for batteries. If the cell gets too hot, it causes internal damage to the cell.”
“Batteries in a car have much more sophisticated thermal management that tries to keep the battery temperature in its sweet spot, not too cold, not too hot,” he explained.
Avoiding the solid waste apocalypse
As batteries degrade, the study found that an EV’s range decreases. For example, Tesla’s Model S, with its 100-kilowatt-hour battery, loses about 75 miles of range after 100,000 miles.
However, the older Model S, which has smaller 70 and 85 kWh batteries, lost almost no driving range after covering the same distance.
By comparison, the 2014 and 2017 BMW i3s have reached 100,000 with about 80% of their original battery capacity remaining.
Meanwhile, the 2021 Hyundai Ioniq 5 lost about 15 miles of range in the first 20,000 miles, but almost no further degradation until 90,000 miles.
While some see EVs as an essential step towards climate change, others see a deluge of hazardous waste generated by cars. According to some experts, it is not necessary.
“As EV production grows, the challenge of managing consumables inevitably looms, but companies like Redwood Materials, founded by Tesla co-founder JB Straubel, Li-Cycle and others are working to get ahead of this problem and recycle and recover EV batteries responsibly,” said Sanchez.
“Some utilities are also repurposing used electricity batteries as a way to maintain grid load levels and nighttime renewable energy,” he continued.
“Those who argue that EV batteries will be a catastrophic environmental disaster fail to consider the value of the elements and metals recovered from EV batteries, which will be in significant demand in the future,” he said.
Abuelsamid agreed that we can avoid the solid waste problem.
“During recycling, you can recover 98% of the important minerals in a battery,” he said. “Since it is unreasonable to expect that we will meet all the demand for batteries with virgin materials, the industry will become much more dependent on recycled materials.”
“We don’t want to throw the batteries into landfills,” he announced. “It is not a viable option.”