Smarter Software Speeds Up Smartphone Charging
Rather than trying to build a better battery, startup Qnovo bets it can improve the one that’s already in your smartphone.
More than 1.8 billion mobile phones were sold worldwide in 2013.
One of the most frustrating things about smartphones—how long they take to recharge—could soon be one-third as frustrating. A startup called Qnovo, based in Newark, California, uses a technology that constantly checks and adjusts the flow of power during recharging to charge batteries faster and increase their lifespans.
As smartphones, tablets, and even electric cars have become more popular and powerful, batteries have become a huge problem: they never seem to last long enough; they take too long to recharge; and they hold less of a charge over time.
Some hope to solve these issues using new battery materials. Qnovo, in contrast, has developed a chip and software that can charge a phone’s battery in a third of the normal time. While a phone normally connected to a wall outlet with a five-watt charger may get an hour and a half of talk time after 15 minutes of charging, Qnovo’s technology could yield three or even six hours of operation from that same charge.
The company also says its technology can help lithium-ion batteries—which degrade over time due to chemical reactions that can occur during the normal charging process—hold up for many more charging cycles.
Qnovo CEO Nadim Maluf predicts that the company’s technology will be available on some smartphones next year. He says he is talking to unspecified phone makers about embedding Qnovo’s software on their devices or, for even better performance, installing a chip that manages the charging process.
Normally, during recharging, an adapter forces lithium ions from a battery’s positive electrode, or cathode, to the negative electrode, or anode, at a continual rate until the battery is full. Over time, the battery degrades due to issues like lithium plating (where lithium ions bond to each other) that occur as a result of pushing these ions from one place to another. Speeding up the charging process by forcing more power into the battery will only ruin the battery more quickly.
When a phone equipped with Qnovo’s technology is plugged into an adapter, the software sends a pulse to the phone’s battery. The voltage response that comes back from the battery offers information about the battery’s status, such as its current temperature and how it has been charged in the past, and lets Qnovo determine how much power it can safely take from the adapter. This means the battery can be charged as fast as possible while minimizing the degradation.
The company’s software constantly repeats this check-in process with the battery so charging can be adjusted as needed. It also adapts over time to a battery’s properties. “You measure, you act, you measure again, you act,” Maluf says.
While Qnovo can increase charging speeds with software, it works even more quickly with the addition of its chip to a smartphone. The company says it’s talking to phone makers who are interested in adding either the software or the software embedded on a chip it has designed to their handsets.
Even if Qnovo convinces smartphone makers and others of the utility of its approach, there’s still one big problem for smartphone users: capacity. But Maluf believes faster charging will makes this seem less of a problem. “If you have the ability of charging your mobile device fast,” he says, “the anxiety you have about how long it lasts goes away.”
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