Solar Battery Charging

Step 10 Gotchas

Just a few gotchas to help you avoid any errors or misconceptions.

1) Get a multimeter and get a good feel for how your solar panel operates in various weather conditions and at various times of the day. Maximum ratings are all well and good but we don't all live in sunny Florida.

2) Be careful about how much current you pass through your battery. Most modern batteries can be charged at quite a high current. For example you could charge a 2000mAH battery with a 500mA current for just over 4hrs and it would be fully charged - keep on charging it beyond that 4hrs and you could seriously damage the battery ( or even cause an explosion). Nimh batteries have a protective mechanism when they get overcharged and attempt to dissipate the excess current as heat. However they can usually only managed to discharge one tenth of their total current as heat. What this means in practical terms is that if you charge a 2000mAH battery with 200mA then it will survive without a problem if you overcharge it for a while. However if you are charging it with a 500mA current and then overcharge it things get more serious.

I will attempt to expand this tutorial further - if you have any suggestions, additions, corrections then please contact me at [e-mail]

To purchase this kit or any extra solar panels please go to

http://stores.ebay.co.uk/Electronic-Widgets-Inc

Comments

[uberdum05]

An improvement: add a LED with no resistor in series with the positive line on the solar panel to the battery holder. It will serve as a current limiter and a basic display as to how the battery is charging
eg. Brightly lit = charging battery a lot
Not so bright = charging more gently
dim = trickle charge

Also *USE A RED OR YELLOW LED FOR CHARGING SMALL BATTERIES OFF A SMALL PANEL*
Just my ten cents :)
Uber

[Keohohina]

Thanks this has really helped, Im trying tho get a pair of solar panels which are the same size as yours to power a water pump and charge a battery at the same time. Any suggestions

[kylengineer]

i found this very helpful.thanks but i ddnt gt to see the complete circuit with all the components listed from the start,i only saw piece by piece.i would like to see the whole complete circuit.

[lionheartone]

Hi
I am making solar panel jacket. In order to charge phones and i-phones etc
I need some help with circuit. do not know what cicuit to use.

Please help

[popa27272]

i was playing around with my solar powered radio once and noticed that i got less static and the battery charged better when i focused a magnifying lens over it to the point where the solar panel appears at its largest,

just a simple way to increase efficiency of the panel

[coolieo5232]

this was very helpfull, thanks.

[alness]

How to detect the status of batteries of current before charging? Is there any charging indicator?

[geeker]

this isnt so much a comment as it is a qustion. would it be possible to use this on a wind turbine, granted with a bit of beefing up?

[NInja99]

I'm asking the same thing but with a mechanical energy turbine.

[skaar]

yes, on both, but you need to rectify, and if the power fluctuates, you need a regulator, a zener diode over the terminals as regulator will pass excess power back to the generator, saving the battery.