Half a croissant, on a plate, with a sign in front of it saying '50c'
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Laptop Trickle Charger

Emergency laptop charge with a USB phone charger
  [vote for,

Laptop chargers don't always break at convenient times, but when they do, a phone charger is usually close at hand. Laptops should come with a micro USB port (with an internal DC-to-DC converter) to slowly charge the battery. A phone charger wouldn't provide enough power to run the laptop continuously, but it might work in a pinch to provide a presentation's worth of power over the course of a hotel stay.
kevinthenerd, Sep 08 2012


       Most phone chargers can deliver (maybe) 5V, 100mA - 500mW.   

       Most laptop batteries are about 20V. That means a DC-DC cconverter, not 100% efficient. So your 100mA 5V is traded for 20V at- with good design- 15 to 20 mA tops.   

       Compared to the 4A or so that most switchmode laptop PSUs deliver, and the charge time is going to be quite extended.
8th of 7, Sep 08 2012

       My last laptop had 2 chargers go bad (HP has lost a customer forever). I would have loved a backup system at the time to let me use one of my many USB chargers for my laptop. [+]   

       //Most phone chargers can deliver (maybe) 5V, 100mA - 500mW. Most laptop batteries are about 20V// You may be right that the charging would be inefficient (I don't know enough about electricity to argue that) but a Macbook Air has a 7.2 volt battery and most laptops I'm familiar with have 7-14 volt batteries. As far as chargers 5.1V is the max but my phone has a 700mA charger and the charger for my iPad is a full 2.1A
DIYMatt, Sep 08 2012

       Some primates have been trained to count to two. One battery charger for daily computer use. One battery charger as a spare.
Lesser Spotted Kiwi, Sep 09 2012

       Order a $50 charger from HP to keep as a spare my ass!
DIYMatt, Sep 09 2012

       Sorry. Thought you were on Super, same as myself.
Lesser Spotted Kiwi, Sep 09 2012

       Laptop chargers are bulkier and have higher power consumption, both of which make them more susceptible to damage, both physical and electrical. Also, laptop chargers are more likely to travel with the laptop, meaning the cord gets rolled up and tossed into a bag where it's subject to any manner of physical abuse, rather than staying at home plugged in on the kitchen counter like a phone charger. I've had both kinds of chargers fail, but I've definitely seen more broken laptop chargers than phone chargers.
ytk, Sep 09 2012


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