Dual USB Universal Car Charger by the copper top folks

[Nacho_Momma]

This looks promising as a car charger for Nook Color - what do you think?

http://www.duracellpower.com/electronic-chargers/portable-chargers/dual-usb-car-charger.aspx

[bobstro]

If you use the NC cable that came with your NOOK, it will charge. However, it might not charge at full rate, nor with the screen on. The only guaranteed way to charge at full rate, and with the screen on, is to use the B&N cable and AC adapter.

You could use a $30 inverter to provide an AC plug, and put the B&N adapter into that. Tacky, and bulky, but perhaps more reliable.

[MatthewH]

BN does sell a car charger specially for the NC with the needed extra contacts so I would suggest getting that, I have one and it works fine. After CT was hit with two major storms in 2011, both of which took out power to most of Connecticut, I got a 12volt battery pack with a motorcycle-size battery as an additional backup: I figure I can use my NC and cellphone car chargers with it in the event of another disaster.

[j-andersonjma]

The dual port device will work fine with your B&N USB Charger cable.  USB specifications for power are standard even for the Nook family.  The difference is in the cable pinout setup not the power source. 

[MatthewH]

The NC cable and charger have additional contacts in order to supply ~2 amps, with a standard USB connector the maximum current is ~1 amp. I have some devices for my laptop such as external hard drives that need more power than a standard USB connector will deliver, but because these must get their power from the USB ports on standard computers these devices come with two cables which I have to connect at two USB ports on computer and device. B&N made a special cable and high-current charger to enable fast charging. With a non-BN-specific charger the NC will charge, just more slowly. But if you connect an NC to a BN charger with a standard cable you risk overheating the connector if it tries to feed 2 amps through the pins of a standard USB connector.

[j-andersonjma]

MatthewH is correct about the pinout of the B&N cable and their DC adapter.  I am reading off the label of mine;  output is 5 volts at 2000 mA (1000 mA = 1 Amp).  The spec sheet for the Duracell Dual USB states that it is capable of 1 Amp output with one device connected and 2 Amp output with two devices connected.  This means to me each USB port will output 1 Amp.  If you use the Duracell Dual USB device with the B&N cable you will get charge but at a slower rate. (Never use a standard USB cable to charge)  Depending on the price of the Duracell unit you might be better off to purchase the B&N DC charger at about $24.  You get a charging cable, a data transfer cable and the DC plug in unit.  I did notice that the Duracell unit specifically states that it will charge the Nook family of devices.  My guess is that if asked they will admit that it's charge rate will be one half of the B&N expected rate.