Building a portable solar charger for my laptop!!

[calumbo]

Hi All,

I am trying to build a solar charger that can power my laptop (19VD.C, 3.42A, 65W). I have started looking at components and idea's but I am stuck at a few points and need some help. The plan so far is to buy a 80w solar panel, 12v 7ah battery, 5A charge controller, DC-DC converter to take the voltage from 12vDC to 19VDC and then straight into my laptop.

The problem I'm having is deciding if this will actually work (I do not want to buy the components to later find out that it's not suitable). Is this the best option to use these components or can someone recommend anything better? This is the first time I have ever studied or built anything like this so please go easy on me.

Key points:
Its has to be portable.
It has to power my laptop.
It has to be as cheap as possible.
Go easy on me as I'm here for help not a hard time.

If you have any further questions for me I will try and answer them all.

Thanks in advance.

 

[pgib8]

It may or may not work. Often times it's more than just a DC voltage and the laptop will know it's not getting power from its beloved power supply and complain about it. Only one way to find out though.
I have a similar setup myself, except I just use an inverter from 12VDC to 120VAC and then use the native power supply from there. I know it's not very efficient but when you have an 80W solar panel, who cares right? I also tag a car battery along with it. I use it when I go camping (can't be without the laptop).

 

[calumbo]

Thanks for the quick reply.
I might try and downscale my solar charger as I have just had a look at portable solar panels. It seems very large and bulky. How long does your solar panel take to charge the battery(How large is your panel), I understand it will be dependant on the sun? How much battery life do you get when using your laptop?

The battery will be full and I just need the solar panel to charge up the battery while I'm using it with my laptop. I need to get this thing as light as possible as I am going to be carrying it. Using the inverter could be a very good idea.

Your setup looks really good.

Thanks so much for your help.

 

[pgib8]

I've only used it once so far. I don't have the data you are asking for but I can tell you that I always had PLENTY of power (which was the idea of getting a bigger setup).
I wouldn't consider it mobile though, unless mobile in the sense that you're transporting it with a car. The panel is either 60 or 80 watts.

 

[CDRIVE]

I bought one of these on sale for <$30.00 to keep my Tundra on trickle charge because I cycle far more than I drive. I keep it on my dashboard plugged into an accessory jack.
http://www.harborfreight.com/15-watt-12-volt-solar-panel-96418.html

Chris

 

[AnalogKid]

Since the laptop has internal batteries, what is the purpose of the external SLA battery?

Your overall plan should work fine. ebay has many low cost boost converter modules.

ak

 

[calumbo]

I am thinking now that this project is going to cost to much and serve no real purpose. I think all the weight of the components needed to make it work will be to great. I have to carry it on my back and climb ladders!! It is back to the drawing board and to think of a new project that is viable.

Thanks for all your help.