Spoiled By Moore’s Law

By Ann Steffora Mutschler

Over the past 20 years, lithium ion has emerged as the predominant battery technology. While there are a few variants, it seems that for everything from smartphones to automobiles, the same basic technology is being used. Many other technologies that have come and gone over the years—nickel cadmium, nickel metal hydride come to mind in the recent past, but they are basically off the market now.

“Energy efficiencies have gotten pretty good…but the scary thing when you look at it from a capacity and efficiency standpoint with regard to weight and volume, it hasn’t really changed that much. It’s clearly improving, and I think costs have gotten a little bit better, but not all that much either. When you compare it with the electronics that we’re using it with and Moore’s Law, it’s basically standing still,” observed Cary Chin, director of marketing for low-power solutions at Synopsys. “The improvements we’ve seen in the last five years in low power electronics, it’s like a 99.9% to 0.1% improvement in battery capacity on the supply side versus on the usage side. We’re just doing a lot more stuff for the same amount of energy basically.”

He’s not alone in trying to discern progress in battery technology. “The basic battery chemistry hasn’t really changed since probably Ben Franklin,” said Gene Matter, senior applications manager at Docea Power. “What’s really changed is more of the materials science with trying to get the proper types of cathode-anode.”

In terms of new technologies, there are activities happening around the world at universities and research organizations. Everything from variations of carbon nanotubes to batteries based on viruses and fuel cells have been proposed among a myriad other scenarios.

One such effort is happening at Infinite Power Solutions, where researchers have developed a solid-state, thin-film battery, according to Tim Bradow, vice president of marketing at the company. He said these ultra-thin batteries now can be manufactured economically (<$1/Wh) using physical vapor deposition (PVD) thin-film battery technology. These all-solid-state, thin-film batteries claim properties such as thinness (starting at 0.1mm), safety (they cannot burn or explode) and energy densities of more than 700Wh/liter (fully packaged). They believe the technology could even be used for cell phone batteries, barring the cost of setting up a manufacturing plant.

With so many interesting developments, why haven’t we as an industry been able to embrace new battery technologies?

Matter noted, “Battery chemistry from the beaker or test tube to production is a fairly long lifecycle. It’s probably 8 or 10 years in research/pathfinding, then 5 to 7 years in development. Then they finally say, ‘I think I have a variation of nickel metal or cadmium or whatever it might be and we’ve actually seen good improvements in terms of the watt hour per liter or watt hour per kilogram.’ These are the two metrics—how much charge density you can put in a given volume and how much charge density can you put in weight.”

Still, he believes lithium is going to be around for quite a while. “I think folks are looking for battery chemistry to extend what they can with lithium. The battery technology improvements are probably going to be modest—probably 5% to 10% per year improvements over the lifecycle of the new technology until they plateau and then maybe a new chemistry comes along. But we’re kind of in the middle of the lifecycle for lithium ion and lithium polymer.” He expects that we’ll likely approach this plateau over the next few years.

Business dynamics trump cool technology
On the practical side to this, of course, is the business dynamic. “There are three or four major suppliers of all battery technology basically that can afford the fab and the manufacturing—and it’s really kind of nasty manufacturing—then you have standard economies of scale of which a given chemistry and technology that is in full ramp production is going to be cheaper than something new,” Matter said. “Business dynamics trump technology day after day, hands down. One of the big things that keeps the existing technology entrenched is the compatibility of those accessory and aftermarket sale items because the battery chemistries have different charging circuits so they don’t work with the extra chargers. They have different voltage potentials in terms of their cathode-anode voltage potential that actually drives the accessory item batteries.”

Qi Wang, technical marketing group director for low power & mixed-signal at Cadence, noted that it is the killer app that drives change. Until then, it’s mostly in the research lab. “Until you have a good business model, you cannot scale down the cost. Then there’s no profit, then nobody will do it.”

Demand-side will drive change
“With the bulk of our technology, it’s taken probably 20 years to settle in on lithium ion as the fundamental technology today,” said Synopsys’ Chin. “Even if we saw a breakthrough that were manufacturable and repeatable and proven safe over a long period of time, it’s going to take years and years to really roll something else out.”

Interestingly, he said, when looking at some of the articles written today touting breakthroughs in battery technology, they’re only hoping for about a 25% increase in capacity or something similar.

“When you think about that in comparison to Moore’s Law, it’s pretty scary because we’ve been marching down this path for 30 years,” he said. “What’s clearly going to happen in the energy equation—and the funny thing is that it’s going to carry through from mobile devices to electric cars—is really that it’s going to be a demand-side change. When you look at mobile devices, we’ve made unbelievable gains basically using the same amount of power on these mobile devices. Using the same amount of power their capabilities are still growing exponentially. That’s the secret of electronics and Moore’s Law. They can grow like crazy. I think we’ve become spoiled because we expect other things in our lives to grow in that fashion, and they just don’t.”