On a March morning in 2024, a baggage tractor stopped on the tarmac at Frankfurt Airport. The vehicle had been running for three hours. Its lead-acid battery had dropped below usable charge. A technician plugged it into a charging station. Forty meters away, another tractor—same frame, same manufacturer, bought the same year—pulled a train of cargo dollies past the terminal. That one had a lithium iron phosphate pack installed in 2022. It ran for another five hours before the operator took a break.
John Goodenough
John Goodenough arrived at his lab at the University of Texas at Austin most mornings before 8 a.m. He was 94 years old in 2016 when a reporter from the University of Chicago Magazine visited him there. Graduate students and postdocs surrounded him. He had been working on battery materials since the 1970s.
In 1980, at Oxford, Goodenough identified lithium cobalt oxide as a cathode material. Sony used it in the first commercial lithium-ion battery in 1991. That chemistry now powers smartphones and laptops. Goodenough moved to Texas in 1986. He kept working.
In 1997, Goodenough and a postdoctoral researcher named Akshaya Padhi published a paper on lithium iron phosphate. The compound stored less energy per kilogram than lithium cobalt oxide. It produced lower voltage. Goodenough thought the material had limited commercial prospects. Michel Armand, a French battery scientist, called him. Armand saw something else. The iron phosphate structure resisted catching fire. It could withstand temperatures above 500 degrees Celsius before thermal runaway—the chain reaction that destroys batteries. Cobalt-based cells failed below 300 degrees.
The iron phosphate structure resisted catching fire. It could withstand temperatures above 500 degrees Celsius before thermal runaway—the chain reaction that destroys batteries.
The Journey of LFP Technology
Wang Chuanfu, the company's founder, had started BYD in 1995 making rechargeable batteries for mobile phones. By 2024, BYD was selling more electric vehicles than any company except Tesla.
Electric tow tractor with LFP battery pack hauling baggage dollies
Tow tractors pull trains of carts through warehouses and across airport tarmacs. The vehicles weigh between 1,500 and 4,000 kilograms. They haul loads up to 25,000 kilograms. They start and stop continuously. They run in cold storage facilities at minus 20 degrees Celsius. They run on summer tarmacs in Phoenix and Doha at 45 degrees Celsius. Lead-acid batteries have powered these machines for decades. The chemistry dates to 1859. A 48-volt industrial lead-acid pack weighs 900 to 1,200 kilograms. Operators add distilled water every week or two. Sulfuric acid corrodes terminals. The batteries last three to five years. Replacements cost 3,000 to 8,000 dollars.
Lead-Acid vs. Lithium Iron Phosphate
Lithium iron phosphate packs weigh 400 to 600 kilograms for the same capacity. Manufacturers weld steel plates inside the housing to restore counterweight. The cells need no water. They charge in one to two hours. Lead-acid takes eight. CATL and BYD ship iron phosphate cells at roughly 90 dollars per kilowatt-hour. A 48-volt, 400-ampere-hour pack wholesales for 5,000 to 7,000 dollars. The cells last 3,500 cycles. Lead-acid lasts 1,500.
Waev Inc. sells Tiger tow tractors from Irvine, California. The company began offering lithium-powered versions in 2022. Gerry Hoadley, director of ground support equipment at Waev, described the iron phosphate cells at an industry meeting: safer, more stable, longer-lasting. When the batteries reach end of life in the tractors, he said, the cells can go into stationary storage. Power walls. Off-grid systems. Second life.
Global Airport Adoption
Los Angeles International Airport handles 88 million passengers a year. LAX committed to electric ground support equipment. British Airways ran a pilot program there with electric cargo vans. The airline reported 83 percent lower carbon dioxide emissions compared to gasoline vehicles. British Airways announced a multi-million-pound investment in electric ground equipment at Heathrow in 2024. Changi Airport in Singapore converted part of its baggage tractor fleet. Energy costs dropped 25 percent.
The tow tractor market reached 1.9 billion dollars in 2024. Electric units made up 67.3 percent of sales. Market analysts project 3 billion dollars by 2034. The spare battery logistics market for airport ground equipment—the infrastructure for charging and swapping packs—reached 1.62 billion dollars in 2024. Projections put it at 4.46 billion by 2033.
Lead-acid holds on in some segments. More than 70 percent of backup power systems in European data centers still use the old chemistry. Single-shift warehouse operations with regular eight-hour charging windows see less benefit from faster-charging lithium. The recycling rate for lead-acid batteries exceeds 99 percent. Lithium-ion recycling runs around 15 percent. The lead goes back into new batteries with no loss of performance.
Toyota Material Handling introduced iron phosphate tow tractors in Japan in 2023. Jungheinrich offers iron phosphate across its warehouse vehicle line in Germany. BYD's industrial tractors run on the same Blade Battery cells as its passenger cars. Hyster-Yale developed modular battery systems. Operators swap packs without shutting down.
Goodenough never made money from the iron phosphate patent. Licensing disputes followed the technology for years. A Canadian company sued A123 for infringement. A researcher who had worked in Goodenough's lab filed patents in Japan without crediting him. Goodenough gave away his prize money. He endowed scholarships.
He died in June 2023. He was 100 years old. His lithium iron phosphate cathode had waited 25 years to find wide use. Power tools came first. Electric buses followed. Tow tractors came later. The airports and warehouses where these machines run handle billions of packages each year. The compound he once dismissed now powers baggage tractors at Heathrow, Frankfurt, LAX, Changi.