LAMPE-ONNERUD had her career-altering moment in 1999, at the 40th Battery Symposium, in Kyoto. She ruffled a few feathers there by pointing out in a talk that the energy density of lithium-ion batteries used for laptop computers, at 40 watt-hours per kilogram, was already getting uncomfortably close to that of your basic hand grenade. That density, the amount of energy stored in a certain mass, had been going up like a rocket as manufacturers competed fiercely for a growing market.

At the time she was a partner at consulting firm Arthur D. Little, in Cambridge, Mass., advising battery companies, doing market forecasts, and troubleshooting technical and manufacturing ­problems. She gave lots of speeches at conferences, most of them saying the same thing: as lithium-ion makers squeezed more and more energy out of their batteries, they were also going to get squeezed on cost. Put those two trends together, she told battery makers, and bad things might happen. None of the manufacturers became overly alarmed.

Then, in 2002 and 2003, battery manufacturers indeed started having problems with unpredictable failures—none of which, at this stage, involved flaming consumer goods. Manufacturers addressed the failures, “but the solutions were always just patches,” she says. By 2004, Lampe-Onnerud was tired of helping the industry slap on Band-Aids: “I wanted to take a step back and think about the whole battery as one system.” And she couldn’t do that within Arthur D. Little.

So on Halloween 2004, she cleaned out her office at Arthur D. Little, said good-bye to her colleagues, and went trick-or-­treating with her kids. The next day Lampe-Onnerud dropped her children off at preschool and then walked up the stairs to her study, where she opened her laptop, took a deep breath, and began to think about lithium-ion batteries in a way no one else ever had before.

Lots of people find their life’s calling only after circuitous adolescent self-discovery. But not many engineers find their way after rejecting opera singing and medicine. Christina Lampe grew up enchanted with opera in her native Sweden. But her father, Wolfgang Lampe, a power engineer who was named an IEEE Fellow for his innovations in high-power transmission, encouraged her to make performing arts a sideline and pursue a more traditional career in math or science.

She did find science fun as a child, playing with electronics and chemistry kits. By the time she was 12, she was concocting fireworks in a basement bathtub, slapping out stray sparks with damp ­towels. In high school she applied to and was accepted by a prestigious eight-year program in Sweden that would end with a medical doctorate. But during her senior year of high school, in 1985, with memories of a recent fun-filled summer in Oregon fresh in her mind, she instead accepted a scholarship from a Swedish-American associa­tion to go to college in the United States. She spent a year at Elmira College in New York, taking double the normal course load and studying English literature, business, and various sciences and working for one of the chemistry professors as a lab assistant. In the spring, the students voted Lampe “Miss Elmira.”

She went back to Sweden to finish her education at Uppsala University, but by this time she’d turned away from medicine for good. An Elmira chemistry professor, Pierre-Ives Bouthyette, had convinced her that chemistry was far more interesting than anatomy. Anatomy was simply memorization, while chemistry was literally the stuff of the world. With chemistry, “you had to see beyond what the science was,” she says, and understand what the science could make happen.

PHOTO: Chris Mueller

These days, Lampe-Onnerud is working 80‑hour weeks, meeting with potential customers and investors, overseeing the manufacturing ramp-up in China, and working with members of the company’s executive team around the world. On a typical day, she’s up at 5 a.m. to check in with Boston-Power’s team in China; at 7 a.m. she reads her e-mail, and then from 7:15 to 8:30 she’s feeding the kids breakfast and getting them ready for school. From 9 a.m. to midafternoon it’s meeting after meeting. She and Rick Chamberlain, Boston-Power’s vice president of engineering, discuss a new customer at 10 a.m. [left]. Around noon, Lampe-Onnerud meets with senior scientist Yanning Song to discuss test results [center], and then at 1:45 with members of the company’s electronics group [right].

It came easily enough to her. Lampe began graduate studies at Uppsala, focusing on copper deposition on semiconductor wafers for her master’s work and analyzing cathode materials for lithium-polymer batteries for her Ph.D. While completing her degree, she collaborated with a battery company called Danionics, in Odense, Denmark. Danionics patented the synthesis of some of the vanadium-oxide cathode materials she worked on for her Ph.D.

On the day Lampe was due to defend her Ph.D. thesis, she publicized the event; she was giving a live interview to a radio journalist as she entered the room. “The thing that separates Christina from others is her ambition,” says Josh Thomas, the professor who supervised her Ph.D. work.

She could hardly have timed her thesis better. When she got her Ph.D. in 1995, commercial lithium-ion batteries were still fairly novel. Lampe quickly became known as a lithium-ion cathode expert. Not that she fixated completely on batteries: she also worked for the town of Uppsala, leading its 120-singer chorus, and married her high school sweetheart, Per Onnerud, who was studying chemistry and math and playing jazz trumpet in a local band.

After graduation, the two went to MIT as postdoctoral ­researchers. Lampe-Onnerud worked part-time for an MIT spin-off, Quantum Energy Technologies, where she concentrated on batteries and displays, before moving in 1997 to Bell Communications Research (Bellcore), in Red Bank, N.J., as director of energy storage. The Bellcore gig was fun but short-lived. Executives at Arthur D. Little, the management-consulting firm, had begun wooing Lampe-Onnerud the day she left Massachusetts for Bellcore. They called at least once a month. They sent gift baskets. And finally they offered to hire her with her husband and assign them to work together, something Bellcore wouldn’t do.