nookcharger_thumb.jpgTechRadar has just shared a post which should be of interest to all users of ereading devices – even if it mostly concerns smartphones. Of course, many keen consumers of ebooks these days are reading on their smartphones anyway, but even those readers who stick to Kindles or Kobos only can still learn from this.

In answer to the perennial question “should we unplug our chargers each night?,” TechRadar’s David Nield compiles up-to-date tech opinion and the results of recent efforts to push battery life and power management. He instances, for example, the International Energy Agency‘s 1-Watt Plan, which “proposed that all countries harmonise energy policies to reduce standby power use to no more than one watt per device.” That initiative dated back to 1999, but it does finally seem that progress has been made. “When your charger is plugged in but not connected to a device (while you’re out at work say) it’s only using the equivalent of a few pence worth of energy over an entire year,” points out Nield, although he also cites sources to show that a household – and the entire planet – can save power “by unplugging all of the devices that are on standby or connected to the mains during the night, that includes smartphones, but also microwaves, television sets and routers.”

As this suggests, the key issue is whether your device stops charging when it reaches full power. For devices fitted with rechargeable lithium ion batteries, which basically constitutes almost all ereaders and smartphones currently sold, “if these batteries are overcharged or completely drained, they can become very volatile and dangerous, which is why modern chargers are designed to stop those two things from happening: they will actually cut out the power once a phone reaches 100%,” says Nield. As a result, they only trickle-charge after reaching full charge once. However, Nield also declares that: “That’s one of the reasons why it’s important that you use the charger that came with your phone whenever possible, otherwise there’s the risk of causing unnecessary damage to it.” I don’t ever recall a single instance of a problem with a different charger for my devices, so long as their specs were remotely compatible. (And as a reminder, pick the same voltage as your device requires, but the device and charger will compensate for differences in amperage specs – just don’t expect a low-amp device to charge your machine too quickly.)  But that’s the official position.

Actually prolonging the life of your device batteries can depend on more arcane factors like heat. Battery University has a complete rundown on these. Enough to say that leaving your device in a hot car can cut into its battery’s useful life more than repeated recharges ever can.


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