Solar battery charger help

System

Hi there,

This is my first post on this website. I have recently put together a small solar project that consists of the following parts;

1. 35 amp deep-cycle solar battery
2. 7 amp solar controller to stop overcharging and discharge.
3. 200 watt inverter
4. 12v .2 amp solar panel

After putting this together, I figured out that a .2 amp panel will take forever to fully charge the battery. I decided to upgrade my panel. I am on a budget, and I want to build my own out of photovoltaic cells wired in series to save money.

I was told that when I wire 36 .2 amp cells I still only receive .2 amps total. Is this correct?

Please let me know if you know of any cheap cells/panels that you think will fit my needs. Thanks 8)

BB.

Re: Solar battery charger help

Yes, you are correct. Wiring cells in series increases the voltage and not the current.

For you system, you should be aiming at ~3.5 amps @17 volts or so... (5-13% of battery Amp*Hour rating is recommended charging current).

You are looking at a ~60 watt panel (10% of battery amp*hour rating -- P=V*I=17V*3.5A=60watts). Roughly $300-$350 list price for a good quality panel.

-Bill

System2

Re: Solar battery charger help

Okay, thanks

I found a guy on ebay that sells 36 3.6 amp cells for $140.00. I think I may buy them, and then build the panel myself

mike95490

Re: Solar battery charger help

idontknow307 wrote: »

Okay, thanks

I found a guy on ebay that sells 36 3.6 amp cells for $140.00. I think I may buy them, and then build the panel myself

While it will be fun, and you may learn a lot, you will find that a home-built panel will not be easy to either build, or handle. If not sealed really well, moisture will get in and attack the individual cells, and they will die slowly. For a 2 or 3 year worth science project, it's fine, but don't expect to get 20+ years out of it.

System2

Re: Solar battery charger help

Thanks, I'll keep that in mind.

Do you know of any ways to waterproof solar cells, or a solar panel. I would like to waterproof my solar panel that I have now so I can keep it outside.