Can power supplies catch up with requirements for sophisticated, feature-rich mobile devices?

By Craig Kuhl

Wireless Week January 01, 2008

The good news? The demand for thinner, smaller, fully loaded handsets with backlighting, video, 3G technology and a host of features is surging. The bad news? These power-hungry devices are driving the need for more efficient batteries and other forms of power production and management. And there is no clear-cut solution.

Dueber: Consumers
are requiring more
power performance
from devices.

“The quest for more power for mobile devices is insatiable and will continue to be an issue with each new capability,” says Ross Dueber, president and CEO of ZPower, a developer of rechargeable silver-zinc batteries for mobile applications.

“Smartphones, 3G technologies and new content using Wi-Fi and WiMAX will dictate power consumption on handsets, which will certainly go up. That’s the way the world is moving,” Dueber says.

And the number of smartphones, cameraphones and multifunctional mobile devices just keeps growing, according to a recent IMS Research study, which predicts the smartphone segment will represent 25% of the total mobile phone market by 2012, with more than 1.5 billion being sold.

“Handset manufacturers now realize people will be enamored with new, cool phones. But it doesn’t take long for customers to figure out the battery life is short,” says In-Stat Research’s Allen Nogee. “The word will get out, and carriers and manufacturers are cognizant of that. And with Wi-Fi, Bluetooth, video, backlights all using more power, it’s a significant issue,” Nogee says.

Significant enough for handset manufacturers such as Motorola to deepen and widen its exploration of new battery and power production technologies and strategies.

“People are using mobile devices more hours. We’re trying to figure out how to get more capacity, but there’s no silver bullet. We get about a 5% increase in capacity each year, and we’re looking for new technologies, but they’re not in sight,” says Jerry Hallmark, manager of energy system technologies for Motorola’s Mobile Devices Group.

Motorola, along with a growing number of handset manufacturers and their supporting cast of power source providers, are looking at both methanol and hydrogen fuel cells, and next-generation iterations of lithium batteries to power the onslaught of multifunctional devices.

“The No. 1 customer complaint is battery life. Now, with e-mail, Internet, music and other features, it’s very significant for smartphones,” Hallmark says. “We’re also working on portable chargers to get longer battery life, and harvesting energy in the field, like solar, and looking at charging kiosks and fuel cells. And, we’re spending at least as much effort on reducing the power draw. But each requires a different type of conversation,” he says.

One key conversation that must take place is power management, says Gerry Purdy, vice president and chief analyst of mobile wireless for the research firm Frost & Sullivan.

“They must get smart about power management. That’s the mechanism we’ll see longer term. The solution is not with nuclear batteries, but with finding new, organic displays with less power consumption. People want thinness, but new technologies are based on lithium. However, people are already making those unconscious tradeoffs of features versus battery life, so today’s technologies are good enough. But we should think about being innovative on powering, not just batteries,” says Purdy.

Kahn: Need to ensure
at least one day’s
worth of talk time.

Part of the management equation is recharging batteries, a strategy which is gaining momentum among handset manufacturers as part of a holistic approach to powering next-generation mobile devices. “If new battery technology increases life by 10%, that’s great. But there are other developing technologies to better charge the battery, like a charging pad using magnetic radiation. Phones are now using Bluetooth, and also communicating with headsets, so more power is needed. We want to ensure at least one day of talk,” says Muzib Khan, Samsung’s vice president of product management and engineering.

But with customer expectations for state-of-the-art and compact devices, the power solution has to remain in lock-step with that overall design. “The design process is now a powering process, and the bar is going up with smartphones, PDAs, lots of data, voice, always-on and browsing. We have to account for higher battery usage and charging phones. It’s a holistic thing,” Khan adds.

Designing slimmer, multifunctional handhelds that can house more power is a challenge, especially for power source providers such as Camarillo, Calif.-based Semtech Corporation. “We’re being asked to optimize efficiency and burn as little battery current as possible with functions such as backlighting, which really burns current. So, design has started to take a more central role. The maximum size of our chip is one-half millimeter, half of what it used to be, and you can stack them to make other features possible. But it’s still like fitting a size 10 foot into a size 4 shoe,” says Tom Karpus, Semtech’s director of handheld systems and applications engineering.

Bradner: Fuel cells
for devices still on
the drawing board.

The move to more efficient lithium-type batteries, some experts say, is one solution to the growing mobile device powering issue. “In time, the move from lithium-ion to lithium polymer solutions will improve, and we’re being asked to do more in that area. But we’re watching the trends with devices like smartphones and working on external battery packs for mobiles and smartphones, along with rechargeable solutions and other products like solar, which can’t power a device by itself so must charge from another power source,” says Andrew Bradner, product line manager for American Power Conversion.

Fuel cells also are on the drawing board, but they have been there for years, admits Bradner. “We haven’t seen a commercially viable solution yet that will fit into the form factor of today’s handhelds.”

The buzz in the mobile device powering community, he notes, is in contactless charging stations and power management. “The buzz is not with new power sources, but how convenient can you charge batteries. There are some battery cells capable of rapidly charging a battery up to 80% capacity. The question is how to get standardization in the device community. Some have agreed to standardize their charging ports, but they’re struggling with that because they all want an edge.”

Just who gets that edge is likely to be determined by innovative new technologies and strategies that can combine design, space and power. “We don’t want batteries to drive the overall form factor of mobile devices, or limit the capabilities because of battery size, even though it’s a key part of the device,” says Dueber. “It’s about how much space do I have and how much energy do I need. There’s no getting around that. And energy strategies for the new mobile devices are dictated by fundamental laws of science. So we must be efficient with what we’ve got. And we’re doing better with that,” he says.