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how do I hook a 8 watt solar panel to a battery? or anything? Answered

I bought an 8 watt solar panel. Now what? what kind of cords do I buy? how do I use the sun to charge a small battery?

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Trevcharl (author)2009-03-18

The maximum output voltage of the solar cell, may be a bit of a problem. If it exceeds 13.8v in full sunlight, and there are no components between the cell and the battery, then the battery will be overcharged if charging cycles are longer than load cycles. If you go below 13.8v then the battery will not get a "full" charge. I assume you are going to use a lead acid battery (car battery)? If you use Nicads, then the current will be the factor to consider, which is somewhat easier as current limiting is done with a simple resistor. A diode will drop the voltage from .6v to 1v depending on the current flow, a Nicad is usually charged at 1/10th of the full capacity. Whatever the case one has to ensure that batteries are not damaged by overcharging. The lead Acid battery will need a series regulator providing 13.8v exactly, and this can be left on forever, without damaging the battery. Nicads can overcharge as well, some sort of sensor or timer is needed to allow the battery to charge fully before switching off. This is a bit more complicated than the series regulator for lead acid cells. Look at a LM317 Integrated circuit for the series regulator. Otherwise you will have to monitor the battery and switch off manually when fully charged.

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user
11010010110 (author)2009-03-17

get diode for the same A as the panel or more panel + to diode in diode out (end with silvered or black line) to battery + panel - to battery -

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lemonie (author)2009-03-17

Why did you buy it, and what cords / outputs does it have? L

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