How do I power a laptop from a 12-V car battery?

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pete

Hi folks --

I want to run a laptop from a 12-V automobile battery. What do I need
to do that in a straightforward, vanilla, bulletproof, reliable way?

Thanks!

-- Pete
 
In alt.comp.hardware.pc-homebuilt pete said:
Hi folks --

I want to run a laptop from a 12-V automobile battery. What do I need
to do that in a straightforward, vanilla, bulletproof, reliable way?
Click to expand...
Buy an adapter.
 
pete said:
Hi folks --

I want to run a laptop from a 12-V automobile battery. What do I need
to do that in a straightforward, vanilla, bulletproof, reliable way?

Thanks!

-- Pete
Click to expand...
The most flexible way is to use an inverter. This will allow use of our
things, like a DVD player also, 12VDC adapters tend to be expensive and
limlted to a particular machine, while inverters are cheaper and will
support a wide variety of machines.
 
The most flexible way is to use an inverter. This will allow use of our
things, like a DVD player also, 12VDC adapters tend to be expensive and
limlted to a particular machine, while inverters are cheaper and will
support a wide variety of machines.
Click to expand...

I don't know enough about it to even guess, but I was hoping that,
because the laptop runs from an internal DC-battery source, that I
could come out with 12V from an external battery and somehow convert
that 12V to whatever DC voltage the laptop needs.

Is that possible without first converting to AC?

Thanks again.

-- Pete
 
pete said:
I don't know enough about it to even guess, but I was hoping that,
because the laptop runs from an internal DC-battery source, that I
could come out with 12V from an external battery and somehow convert
that 12V to whatever DC voltage the laptop needs.

Is that possible without first converting to AC?
Click to expand...

Unlikely. Most laptop batteries are 18-20V, not 12V.
 
pete said:
I was hoping that,
because the laptop runs from an internal DC-battery source,
that I could come out with 12V from an external battery and
somehow convert that 12V to whatever DC voltage the
laptop needs.

Is that possible without first converting to AC?
Click to expand...


If you don't need 117VAC for some other device's wall wart
power supply module (such as a printer or external hard drive),
you can keep the parts count (and weight) down with an adapter.
Just Google for "12vdc laptop adapter".
Here's just one hit out of many:
http://www.meritline.com/car-power-adapter-laptop-notebook-computer.html

*TimDaniels*
 
Hi folks --

I want to run a laptop from a 12-V automobile battery. What do I need
to do that in a straightforward, vanilla, bulletproof, reliable way?

Thanks!

-- Pete
Click to expand...

I would check the voltage out put of your laptop.
 
pete said:
I don't know enough about it to even guess, but I was hoping that,
because the laptop runs from an internal DC-battery source, that I
could come out with 12V from an external battery and somehow convert
that 12V to whatever DC voltage the laptop needs.

Is that possible without first converting to AC?
Click to expand...
...snip,,
Answering that one, specific question: yes. That's what an invertor
does: changing a dc (straight-line) voltage to pulsating dc voltage enables
amplification to *higher* dc voltages. Using a mere adapter, a wire whose
one end plugs into cigar lighter and other end into laptop *may* supply
LOWER dc voltages, but not HIGHER. So, beware! It takes those
adaptor-fittings PLUS an invertor to allow higher dc voltages from cigar
lighter. And, as a.p. said, lots if not most laptops operate on nearer to
18-20 volts dc.
BTW: got a neighbor who asked why his car-adapter operated his laptop
but failed to re-charge his laptop-battery. Turns out he has a mere
adapter--meaning it operates his 19-volt laptop on the car's 12 volts. I
thought he was being stubborn by not tossing it; but now, almost 2 years
later he's still running it that way--and apparently w/o troubles. I'm sure
it runs in a step-down mode and I feel that eventually *may* take a toll on
his system. Of course, he still cannot re-charge his 19-volt battery from
his 12-volt lighter!
HTH, s
 
sdlomi2 said:
Using a mere adapter, a wire whose one end plugs into cigar lighter and other
end into laptop *may* supply LOWER
dc voltages, but not HIGHER.
Click to expand...


Some retailers call a simple plug interface an
"adapter", some call a DC-to-DC power supply
an "adapter". This is an example of the former:
http://www.radioshack.com/product/index.jsp?productId=2289559
This is an example of the latter:
http://www.meritline.com/car-power-adapter-laptop-notebook-computer.html

*TimDaniels*
 
Timothy Daniels said:
Some retailers call a simple plug interface an
"adapter", some call a DC-to-DC power supply
an "adapter". This is an example of the former:
http://www.radioshack.com/product/index.jsp?productId=2289559
This is an example of the latter:

http://www.meritline.com/car-power-adapter-laptop-notebook-computer.html

*TimDaniels*
Click to expand...
You're exactly right. That 2nd one has what must be a solid-state
invertor to increase 12v to 16,18, 19,20-v, etc. I have one almost
identical and carefully tested the output before plugging my laptop into it.
I don't have a pic, but imagine just the wire and plug-ends but w/o the
invertor-- that's what my neighbor has. IIRC he bought it at a flea market.
Only good for 12-volt (or less) products, def. not higher voltage ones.
BTW: why are u using my last name?:) sd lomi2
 
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