Leaps in lithium-ion battery technology during the last two decades sparked the smartphone revolution and drove the rise of electric vehicles. But these advances came after a long incubation period of research and development, and one expert tells ENR that while gradual improvements will continue for lithium ion, there aren’t any other major breakthroughs in batteries on the near horizon.
“At this current stage, at least for the next decade, I don’t think there will be anything to replace lithium ion for batteries,” says Daniel Abraham, senior material researcher at Argonne National Lab. Abraham’s research focuses on finding ways to improve the performance of lithium-ion batteries without compromising their life, often through subtle tweaks in the chemistry. “The time to commercialization for these sort of battery systems is at least 10 years, so for now, lithium ion is expected to remain dominant,” he says.
In terms of energy density, battery life, and weight, lithium-ion batteries are the best available option today. They power everything from smartphones to power tools to Teslas on the highway, but improvements will be incremental for the foreseeable future. If construction equipment is going to shift to battery power, it will have to work with the existing technology and focus on better efficiency and power management to meet demands.
“For some equipment that travels at low speeds, we tended to use lead-acid batteries, where they don’t have to go long distances and don’t mind a little extra weight,” Abraham says, citing forklifts and other older battery-powered equipment. “But the great thing about lithium-ion is its energy and power density is really good, so the batteries can be smaller and lighter.” This allows for more batteries to be packed into the same space, allowing for longer runtimes and greater power availability.
There are limitations to lithium-ion batteries’ capabilities. The temperature range in which they work well is largely fixed: Performance declines greatly in sub-zero temperatures, and while the batteries can perform well at high temperatures, it shortens the life of the cell.
Abraham says the success of lithium ion in heavy equipment will come down to the duty cycle. “With construction equipment, it depends on usage. If you are charging and discharging several times a day with high usage in high temperatures, the degradation is faster,” he explains. “So right now we’re looking at how to alter the chemistry to get longer life, to charge at faster rates.” He cites electric buses running on batteries tailored to their work load. “Certain chemistries work for certain operating conditions,” he explains. Lithium ion is versatile, so finding the right cell configuration for the task at hand is key. “There’s not a single chemistry for lithium-ion batteries; they all perform differently but fall under the same umbrella. That’s why lithium ion will be around for decade or more.”