4G, the buzzword given to the next generation of mobile technology, promises increased data speeds for the next generation of high-bandwidth mobile users. More seldom mentioned is what seems to be the major trade-off for the first generation of 4G-equipped technology: reduced battery life.

Device manufacturers generally present battery life on the basis of two metrics. Stand-by time measures the amount of time that a battery can run a device that is sending or receiving calls. The other metric, talk time measures the amount of time a battery can power a phone that is in actually in use.

Technical specifications for Samsung's Epic 4G, for example, give the phone a talk time of six hours and a stand-by time of twenty-one days. Specifications for Motorola's Atrix, by contrast, give the phone a 9 hour talk time.

But listed technical specifications are results of tests done in a controlled setting, and tend not to reflect the actual, real-world usage of consumers.

Mark Lowenstein, managing director of consulting firm Mobile Ecosystem, notes reconciling a device's technical specifications with actual usage is difficult. The way the devices are actually being used is going to affect the battery life, he said.

ABI Research Senior Analyst Michael Morgan agrees. The whole comparison is broken. Is talk time really what you are talking about here?

That disconnect has not been a major deterrent for consumers. Though equipped with a six-hour battery life HTC's EVO still sold well. I think people for the most part understand the trade-offs, Lowenstein said.

The problem might lie in how in manufacturers estimate battery life. As bandwidth-intensive practices like watching mobile video become more and more widespread, metrics such as talk time are becoming less meaningful. Most people are using their phones for as much as data as much as talk time, Lowenstein said. ABI's Morgan agreed. The way things are being used now, it doesn't do a good job relating to how the battery life is measured.

Issues of battery life aren't at all unique to 4G phones, and battery capacity poses a major concern to device manufacturers as a whole. A six-hour battery life, in that respect, isn't unique compared to 3G phones with similar specifications.

To that end, phone manufactures might be better served dropping the talk time metric and adopting something more relevant to how consumers actually use their devices.

One alternative might be hours of data use. But data usage is only a part of the reason for increased battery drain in phones. Many mobile devices now have relatively large screens. Those displays use a lot of power. Morgan says the combination creates the perfect storm for battery drainage. That what's really, really sucking the power out of these things, he said. As a result, most phones feature options to reduce screen brightness or automatically dim after periods of non-use.

Some manufacturers rely on changes in processor technology. Motorola's Atrix features a dual-core processor, technology designed to reduce drain on the battery. But that won't always do the job. Technically a dual-core phone should deliver better battery life because it takes less power to run two cores at half power than one core at full power, Morgan said. But the power-saving mechanisms are not enough to prevent the battery drain caused by processor-intensive video games, for example.

Some have simply boosted battery size. But that makes the phone itself bigger. But consumers have become used to smaller phones and would be unlikely to go back to the days of phones that didn't fit into pockets.

Morgan argues that manufacturers would be better-served by investing in better screen technologies. The batteries are never going to keep up with the phone, he said. Batteries, unlike other electronics, can't get smaller the way processors do as the energy in them is partly dependent on the volume of material. Innovations on that front are harder to come by, as research into how to make batteries more efficient is tied to some basic laws of chemistry and physics.

In the end, short-term solutions, Mobile Ecosystem's Lowenstein, noted, might come from manufacturers getting a better sense of how consumers are using phones now. The more we learn about how people are using 4G networks, the smarter we can be about getting the most out of the batteries that we have, Lowenstein said.

Storm Battery Storm Management