[Q] using laptop battery as usb charger

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maxlieb

Senior Member
Sep 16, 2011
139
32
I bought a crappy battery pack from dx.com.
the battery works but makes a horrible noise when connecting the phone to the 2A port ... 1A no problem
also it was cheap, chinese, and labled "power bnak" instead of "bank"... total crap

and then I thought... I have a practically new perfectly good huge capacity 12 cell laptop battery that is just sitting on the shelf doing nothing since I don't carry around my laptop most of the time and its connected to ac power with battery disconnected all the time....

what if I could connect a Usb port directly to the battery?
It could be a really overkill emergency charger!

Anyone knows how this can be done?
 

maydayind

Senior Member
Dec 10, 2011
738
130
I bought a crappy battery pack from dx.com.
the battery works but makes a horrible noise when connecting the phone to the 2A port ... 1A no problem
also it was cheap, chinese, and labled "power bnak" instead of "bank"... total crap

and then I thought... I have a practically new perfectly good huge capacity 12 cell laptop battery that is just sitting on the shelf doing nothing since I don't carry around my laptop most of the time and its connected to ac power with battery disconnected all the time....

what if I could connect a Usb port directly to the battery?
It could be a really overkill emergency charger!

Anyone knows how this can be done?


Wrong voltage.. U would frie your charging circuts..
 
Dec 2, 2012
29
1
It's possible

Some laptops will keep power flowing to USB ports without being fully on- possibly in sleep mode. Recommend doing that if that's the case, although that's quite heavy to carry around just for charging your phone.
 

hotrodwinston

Senior Member
A multi meter can tell you what voltages are coming off the laptop battery and radio shack or a local electrical supply store can get you the parts to convert the voltage to the same as the battery on the "power bnak" then it should just be a matter of making sure you have solid connection and plug in - that big of a power source would be great for camping or power outages.